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Myocardial infarction (MI) is one of the common cardiovascular diseases that occurs with a blockage in one or more of the coronary arteries to lead to the damage of the myocardium, resulting in a life-threatening condition. To repair the damaged myocardium in MI, researchers are looking forwards to new ways to postpone the progression of myocardial injury. Cardiac patches, the scaffolds layered on the heart surface, can provide mechanical support for the infarction site and improve cardiac function by delivering various bioactive factors or cells, showing considerable curative effect in the treatment of MI. Biomaterials with certain biocompatibility and mechanical properties have received widespread attention for the application in cardiac patches. In this review, we focus on the recent progress on these biomaterials-based cardiac patches, which could be categorized into two types according to the sources of materials including (ⅰ) natural materials and (ⅱ) synthetic materials. The major advantages and current challenges of each type are discussed and a brief perspective on the future research directions is presented.

Determination and conceptualization of atomic structures of metallic glasses or amorphous alloys remain a grand challenge. Structural models proposed for bulk metallic glasses are still controversial owing to experimental difficulties in directly imaging the atom positions in three-dimensional structures. With the advanced atomic-resolution imaging, here we directly observed the atomic arrangements in atomically thin metallic glassy membranes obtained by vapor deposition. The atomic packing in the amorphous membrane is shown to have a fractal characteristic, with the fractal dimension depending on the atomic density. Locally, the atomic configuration for the metallic glass membrane is composed of many types of polygons with the bonding angles concentrated on 45°–55°. The fractal atomic structure is consistent with the analysis by the percolation theory, and may account for the enhanced relaxation dynamics and the easiness of glass transition as reported for the thin metallic glassy films or glassy surface.

Solid solution strengthening is one of the most conventional strategies for optimizing alloys strength, while the corresponding mechanisms can be more complicated than we traditionally thought specifically as heterogeneity of microstructure is involved. In this work, by comparing the change of chemical distribution, dislocation behaviors and mechanical properties after doping equivalent amount of tungsten (W) atoms in CrCoNi alloy and pure Ni, respectively, it is found that the alloying element W in CrCoNi alloy resulted in much stronger strengthening effect due to the significant increase of heterogeneity in chemical distribution after doping trace amount of W. The large atomic scale concentration fluctuation of all elements in CrCoNi-3W causes dislocation motion via strong nanoscale segment detrapping and severe dislocation pile up which is not the case in Ni-3W. The results revealed the high sensitivity of elements distribution in multi-principle element alloys to composition and the significant consequent influence in tuning the mechanical properties, giving insight for complex alloy design.

Cardisoma armatum is a typical member of the Gecarcinidae which show significant behavioral, morphological, physiological, and/or biochemical adaptations permitting extended activities on the land. The special gills (branchiostegal lung) of C. armatum play an important role in maintaining osmotic pressure balance and obtaining oxygen to adapt to the terrestrial environment. However, adaptive molecular mechanisms responding to air exposure in C. armatum are still poorly understood. In this study, transcriptomic analysis and histological analysis were conducted on the gills to test adaptive capabilities over 8 h between the aerial exposure (AE) and the water immersion (WI) group. Differentially expressed genes (DEGs) related to terrestrial adaptation were categorized into four broad categories: ion transport , acid-base balance, energy metabolism and immune response. This is the first research to reveal the molecular mechanism of terrestrial adaptation in C. armatum, and will provide new insight into the molecular genetic basis of terrestrial adaptation in crabs.

Attachment of bacteria and subsequent formation of biofilms on material surfaces lead to serious consequences including infection, contamination and biofouling, posing a prominent threat to human health and causing problems in many industries. Therefore, it is highly desirable to endow the surfaces with antibacterial properties. Traditional antibacterial surfaces are designed via either bacteria-resisting strategy to prevent the initial adhesion of bacteria or bacteria-killing strategy to eradicate any bacteria that attach to the surface. However, these single-function surfaces have their inherent shortcomings and cannot realize long-term efficacy against bacteria. In recent years, various dual-function antibacterial surfaces with both bacteria-resisting and bacteria-killing properties together have been developed, showing better performance for combating surface-attached bacteria and preventing formation of biofilms. In this review, we summarize the recent development of these dual-function antibacterial surfaces. We focus on the design principles and fabrication strategies of such surfaces and highlight the representative examples, which are categorized specifically into two types according to the anti-adhesive and bactericidal properties are simultaneous or switchable. A brief perspective is finally presented on current challenges and future research directions.

Single-atom catalysts (SACs) have attracted great attention due to their high atom-utilization and catalytic efficiency. However, a universal synthetic route is still lacking, which restricts the SAC-related investigation and application. Here, we report a simple and cost-effective method to fabricate transition metal SACs through ion exchange and annealing procedures. Benefiting from the "egg-box" structure property of alginate, the metal ion can be effectively anchored into the organic center. Using CuCl2 as a representative transition metal ion, the Cu SAC structure was synthesized and identified by aberration-corrected high-angle annular dark-field scanning transmission electron microscopy and X-ray absorption fine structure spectroscopy. Through optimizing CuCl2 concentration, the obtained Cu SAC exhibited a good oxygen reduction reaction activity, whose onset potential, half wave potential, and limiting current density are all comparable to those of 20 wt % Pt/C. Cu-N4 was identified as the responsible catalytic site. More importantly, other transition metal SACs can be easily synthesized via altering metallic solution, which proves the universality of our proposed method. This work may be valuable for the cost-effective and universal SAC synthetic method development.

Due to the ultrafast crystallization process in the triple-source ligand-assisted reprecipitation (TSLARP) technique the [LyPbBrx] octahedra is easily distorted, resulting in anisotropic two-dimensional nanoplatelets (NPLs) with low photoluminescence quantum yield (PLQY) and poor stability. Unexpectedly, we obtain CsPbBr3 NPLs with PLQY approaching unity and high stability using the TSLARP technique through aging the metal-oleate precursors. We find that the significant enhancement of the PLQY is related to the change of solution chemistry of the Pb-oleate precursor in the aging process. While hybrid CsPbBr3@Cs4PbBr6 NPLs with low PLQY (28%) are formed with fresh Pb-oleate precursor, phase-pure CsPbBr3 NPLs with PLQY of 97.4% are obtained with the aged Pb-oleate precursor. A model that takes into account the transformation of the Pb-oleate in toluene from isolated molecules into clusters after aging is proposed to explain the phenomenon. Our finding highlights the importance of understanding the solution chemistry for the synthesis of the highly luminescent NPLs and provides a new way to break the "blue-wall" in perovskite light-emitting devices.

We consider the least square estimator for the parameters of Ornstein-Uhlenbeck processes $$d{Y_s} = \left( {\sum\limits_{j = 1}^k {{\mu _j}{\phi _j}\left( s \right) - \beta {Y_s}} } \right){\rm{d}}s + {\rm{dZ}}_s^{q,H},$$ driven by the Hermite process Z with order q ≥ 1 and a Hurst index H ∈ (½, 1), where the periodic functions φj(s),j = 1,⌦, k are bounded, and the real numbers μj, j = 1, …, k together with β > 0 are unknown parameters. We establish the consistency of a least squares estimation and obtain the asymptotic behavior for the estimator. We also introduce alternative estimators, which can be looked upon as an application of the least squares estimator. In terms of the fractional Ornstein-Uhlenbeck processes with periodic mean, our work can be regarded as its non-Gaussian extension.

The stimuli-response behavior of energetic materials is strongly affected by the defects in crystals. Improving the performance of energetic materials through defect structure engineering is an eff...

Poly(L-lactide) (PLA)/TiO2/Pt composite fiber membrane with an internal porous channel structure was fabricated by skillfully tuning the breath figure mechanism and vapor-induced phase separation mechanism with solute and solvent matching via one-step electrospinning and applied in photocatalytic hydrogen production for the first time. The unique structure enhances the light absorption ability of the composite fiber and endows it with excellent photocatalytic hydrogen production performance. The hydrogen production efficiency of functional TiO2 particles loaded on the composite was increased 30 times compared with the efficiency of TiO2 particles in the aqueous solution, thus leading to 1.8 times increase in the hydrogen production capability and 5.8 times increase in the quantum efficiency compared with that of the TiO2/Pt control sample. The composite fiber membrane was further assembled into an ultrathin (1.5 mm) and degradable hydrogen energy generator with a high power density of 47 W m−2 and a high UV luminous energy conversion rate of 92.8% under simulated sunlight.

Microfluidic chips with the function of hydrodynamic focusing is widely used in the field of cell electroporation, droplet formation, drug screening and particle enrichment. Due to the small channel size of microfluidic chip, the existing processing methods have the defects of high fabrication cost or low dimensional consistency, the drawback is particularly prominent at small fabrication quantity. In this study, hydrodynamic focusing microfluidic chip was successfully fabricated by Liquid Crystal Display (LCD) mask photo-curing method with high efficiency and precision, the mechanism of curing parameters on the accuracy of microstructure was investigated, the hot pressing process was proposed to realize the bonding of cured photosensitive resin and glass substrate. By analyzing the focusing width of typical cross structure channel, a hydrodynamic focusing chip was designed. The effects of exposure time and single layer thickness on whole curing time was studied, the factors affecting the surface roughness were investigated, and the dimensional accuracy control method was proposed. The effect of bonding pressure on cured resin temperature was calculated and tested. The focusing width was verified by theoretical calculation and experiment. The mechanism for the inconsistency between the experimental focusing width and the theoretical focusing width was analyzed. The research proposed a solution of microfluidic design, fabrication, bonding and testing, which could provide a theoretical and methodological support for the efficient fabrication of microfluidic chips.

Natural DNA was employed for the first time as a phosphorization agent and carbon source to controllably synthesize a RuP2/N,P-codoped carbon composite by a simple "mix-and-pyrolyze" strategy, which displays higher activity for alkaline and acidic HER and neutral activity compared to Pt/C together with outstanding durability.

The novel method for the synthesis of gem-bisarylthio enamines and α-phenylthio ketones was developed via the coupling of α-substituted vinyl azides with thiols in the presence of tetrabutylammonium iodide (TBAI) as a redox catalyst and electrolyte at room temperature. Electronic properties were crucial in the generated products. This protocol features metal- and oxidant-free materials, broad tolerance of substrates, and mild reaction conditions.

This study reports the facile synthesis, characterization and quantitative structure-property relationship analysis of molecular and material properties of tricyanofuran-based (TCF) dipolar heptamethines with different electron donors of indoline ( F1 ), benzo[ e ]- indoline ( F2 ), benz[ cd ]indoline ( F3 ), and Michler’s base derivatives ( M1 and M2 ). The linear and nonlinear optical (NLO) properties of these chromophores have been thoroughly investigated, and the relationship between molecular and bulk response has been analyzed and compared with dipolar tetraene AJLZ53 as one of the best chromophores for electro-optic (EO) devices. In particular, we provide responsible data collection and analysis of optical and EO properties for poled thin films using a widely-recognized and accredited methodology of prism coupling system with the help of rigid oriented gas model. We found that these push-pull heptamethines with synthetic efficacy exhibit high near-infrared absorption, excellent chemical stability and large hyperpolarizabilities ( β ) varied from 1,023×10−30 esu for F1 , 3,047×10−30 esu for M1 , and 3,547×10−30 esu for F3 at 1,304 nm in poled films, respectively. The β values of these molecules are among the highest ones for TCF-based dipolar chromophores, and also agree well with reported analytical results in the solutions. In poled polymers with a modest chromophoric loading density of 1.3× 1020 cm−3, M1 and M2 give a high poled-induced noncentrosymmetric order and relatively large r 33 values around 40 pm V−1 at 1,304 nm, indicative of large μβ values and suitable structural modification for high poling efficiency. Furthermore, a binary EO polymer based on the co-loading of M1 and AJLZ53 achieve a large r 33 value of 143.3 pm V−1 at 1,304 nm. Our studies suggest that concise synthesis and molecular design of push-pull polymethines can be well guided by the tabulation of their linear and NLO properties in bulk materials, and streamline future development of high performance organic EO materials for photonic applications.

Heterogeneous Pd-based catalysts are receiving great attention in cross-coupling reactions due to their distinct advantages of relatively low cost, high stability, easy separation, and recycling. N...

Effective and nondestructive intracellular delivery of exogenous molecules and other functional materials into living cells is of importance for diverse biological fundamental research and therapeutic applications, such as gene editing and cell-based therapies. However, for most exogenous molecules, the cell plasma membrane is effectively impermeable and thus remains the greatest barrier to intracellular delivery. In recent years, methods based on surface-mediated physical membrane disruption have attracted considerable attention. These methods exploit the physical properties of the surface to transiently increase the membrane permeability of cells come in contact thereto, thereby facilitating the efficient intracellular delivery of molecules regardless of molecule or target cell type. In this Review, we focus on recent progress, particularly over the past decade, on these surface-mediated membrane disruption-based delivery systems. According to the membrane disruption mechanism, three categories can be recognized: (i) mechanical penetration, (ii) electroporation, and (iii) photothermal poration. Each of these is discussed in turn and a brief perspective on future developments in this promising area is presented.

Solution-sheared field-effect transistors based on the blend of the high-mobility donor-acceptor conjugated copolymer poly(diketopyrrolo[3,4-c]pyrrole-co-thieno[3,2-b]thiophene) (PDBT-co-TT) and the elastic polymer poly(styrene-butadiene-styrene) (SBS) are demonstrated for stretchable electronics. In this study, PDBT-co-TT serves as a charge transport layer, and the insulating polymer SBS with double bonds is used for improving elasticity. Through combination with solution shearing, the phase separation and charge transport properties of the PDBT-co-TT/SBS blends can be manipulated. Compared with the spin-coated PDBT-co-TT/SBS blends showing lower charge mobilities (~10−3 cm2 V−1 s−1), the solution-sheared polymer-blend films with the PDBT-co-TT content of 20% maintain high mobility (>0.1 cm2 V−1 s−1). The films with 60% PDBT-co-TT can even achieve mobility as high as 2 cm2 V−1 s−1, which is higher than the pristine conjugated polymer. Furthermore, as the SBS content increases, the dichroic ratios of the solution-sheared blends increase, indicating improved alignment of the conjugated polymer chains. The PDBT-co-TT/SBS blends exhibit great stretchability and high charge mobilities even under 100% strain due to their mesh-like morphology. Moreover, solution shearing not only improves polymer alignment but also controls surface morphology to enhance stretchability. This work reveals the importance of solution shearing in high-mobility stretchable polymer semiconductor blends.

(A, B) co-doped TiO2 ceramics attract great interests due to the excellent dielectric properties. In this work, the (A, Ta) co-doped TiO2 ceramics were prepared by a solid state reaction process. The effect of the acceptors ionic radius on the structure and properties of TiO2 ceramics was investigated. According to XRD analysis, the main phase is rutile TiO2 for all samples. Due to the larger ionic radius, it is hard to replace Ti site in TiO6 octahedron. As a result, the content of the secondary phase increased with increasing ionic radius. The dielectric properties were significantly enhanced by co-doping of alkaline-earth ions and tantalum ions, and the best dielectric constant obtained at 3% (Sr, Ta) co-doped compositions, where e’ = 2.1 × 105, tanδ = 0.21. Meanwhile, the XPS analysis suggested that the concentration of the defect dipoles exhibit a maximum in Sr-doped TiO2 ceramics. The larger ionic radius of the acceptors leads to the more stability of the defect structure. However, for Ba ions, the replacement concentration decreased due to the excessive ionic radius, which in turn reduces the defect concentration. This work is meaningful for the further investigations on TiO2-based colossal permittivity materials.

Programmable metasurface enables controlling electromagnetic (EM) waves in real time. By programming the states of active device embedded in metasurface element, the EM properties of the digital metasurface can be changed quickly without redesigning their structures. However, large numbers of long-distance wires are required to connect the programmable metasurface to provide the coded signals from field programmable gate array (FPGA) when controlling the metasurface at a long distance, which is complicated and inconvenient. Here, we propose an infrared-controlled programmable metasurface that can be programmed remotely. The infrared transceiver is able to switch the coding sequences stored in the FPGA controller, thus controlling the voltage on the varactors integrated in the metasurface. Experiment is performed at microwave frequencies, and the measured results verify that the scattering beams of the metasurface sample can be changed remotely by using infrared ray. The proposed infrared-controlled programmable metasurface opens up avenues for constructing a new class of remotely-tuning dynamic metasurfaces.

In this study, the mud-phosphorus slurry was used to simultaneously remove SO2 and NOx. The technology proposed new avenues for the purification and utilization of remove SO2 and NOx in flue gas. The effects of reaction temperature, solid-liquid ratio, and oxygen content on the efficiency of desulfurization and denitrification were studied experimentally. Results show that the parameters were solid-liquid ratio of 5.0 g/40 mL, T = 60 °C, φ (O2) = 20%, Q = 300 mL/min under the best experimental conditions. The maximum amount of ozone generated was 563.8 mg/m3. The reaction time with desulfurization rate ≥ 99% was 340 min; the reaction time with denitrification rate ≥ 99% was 160 min. Response surface analysis method was used to perform a three-factor three-level response surface experiment. Results show that the oxygen content had a highly significant effect on the desulfurization and denitrification efficiency, and the relationship between the desulfurization and denitrification efficiency was oxygen content > mud-phosphorus slurry liquid-solid ratio > reaction temperature. The process is simple, the solid waste is used to treat the flue gas, and the removal effect is good, which is convenient for popularization.

A 3,4-dihydroisocoumarin derivative fused with dihydrothiophene, talarolactone A (1), and two known compounds, terreusinone (2) and 4,6-dihydroxy-5-methylphthalide (3), were isolated from Talaromyces sp. associated with Xanthoparmelia angustiphylla. The structure of 1 was deduced from extensive spectroscopic data, electronic circular dichroism calculations, and X-ray diffraction analyses. A plausible biosynthetic pathway of 1 was further proposed. Compound 1 showed selective antimigratory activity in a wound-healing assay without appreciable cytotoxic activity.

Carbon dioxide (CO2) capture by aqueous alkanolamines is among the most mature and efficient technologies to curb the continuous emission of the greenhouse gas CO2 into the atmosphere. However, the widespread use of this technology is limited, mostly due to the energy penalty during CO2 desorption and amine regeneration. A key point to develop more efficient sorbents is the knowledge of the species formed in solution after the reaction of CO2 with the amine. Qualitative and quantitative analysis of ions in solutions can help to understand chemical reaction processes and probe chemical reaction mechanisms to discern important information including the CO2 absorption and desorption rates, the CO2 capture efficiency, the cyclic capacity, and the energy demand for regeneration, which are essential for the commercialization of this technology. Although many researchers have reported the speciation of primary, secondary, and tertiary amines when reacting with CO2 as determined by nuclear magnetic resonance (NMR) and other methods, a few discussed the state-of-the-art research in this area. This paper aims to review and compare NMR spectroscopy, pH + NMR analysis, and model prediction techniques for determining the speciation of CO2 loaded amine solution, to get information for better understanding the fundamental principles and up-to-date progress applied in various amine-CO2 systems. This review illustrates the applications of these three techniques to observe the morphology of CO2 loaded amine solutions including single amines, blended aqueous amines, and nonaqueous amine solutions. Furthermore, the operating principles are described in detail, and the strengths and weaknesses are discussed carefully. Of the three approaches, NMR spectrometry is proven to be more efficient in determining the proportion of ions in simple amine-CO2-H2O systems; however, for more complex systems, the process efficiency varies depending on the situation encountered. In sum, these three analytical techniques can help to design efficient amine materials with high CO2 separation performance and low energy cost.

In recent years, catalytic hydrolysis of sodium borohydride is considered to be a promising approach for hydrogen generation towards fuel cell devices, and highly efficient and noble-metal-free catalysts have attracted increasing attention. In our present work, Co3O4 nanocubes are synthesized by solvothermal method, and then vapor-phase phosphorization treatment is carried out for the preparation of novel Co−O−P composite nanocatalysts composed of multiple active centers including Co, CoO, and Co2P. For catalyst characterization, field-emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), energy dispersive spectrometry (EDS), X-ray diffraction (XRD) and X-ray photoelectric spectroscopy (XPS) are conducted. Optimal conditions for catalyst preparation and application were investigated in detail. At room temperature (25 °C), maximum hydrogen generation rate (HGR) is measured to be 4.85 L min−1 g−1 using a 4 wt% NaBH4 − 8 wt% NaOH solution, which is much higher than that of conventional catalysts with single component reported in literature. It is found that HGR remarkably increases with the increasing of reaction temperature, and apparent activation energy for catalytic hydrolysis of NaBH4 is calculated to be 63 kJ mol−1. After reusing for five times, the Co−O−P composite nanocatalysts still retains 78% of the initial activity.

Pollution during rapid industrialization process is a serious environmental problem that seriously affects people's lives and livelihoods. Among them, the pollution of excessive heavy metals in wastewater has attracted wide attention. The current study proposes a novel effective and low-cost silica@polyacrylamide composites (SP-C) to capture cadmium ion (Cd2+) from wastewater contaminated by heavy metal. The chemical and physical properties of the surface and interior of silica@polyacrylamide composites were studied by different characterization methods. The adsorption capacity and kinetics of cadmium ions in aqueous solutions using silica@polyacrylamide composites were also studied, and some discussions about the mechanism of adsorption process were made. Silica@polyacrylamide composites showed enhanced cadmium ions adsorption with the maximum adsorption capacity of 211.86 mg/g (pH 6.5, T = 318.15 K), which was fitted by Langmuir model. The adsorption experimental kinetic data of silica@polyacrylamide composites could be excellently verified by pseudo-second-order model. Moreover, a comparison of the cost between the proposed silica@polyacrylamide composites and other reported adsorbents is provided. And the results indicate that the silica@polyacrylamide composites adsorption cost is 0.16 $/g cadmium ion, which means a promising cost-effective adsorbent for cadmium ion removing.

Let $$X^{H(u)}(u)=\left\{X^{H(u)}(u), u \in \mathbb{R}_{+}^{N}\right\}$$ be linear multifractional stable sheets with index functional H(u), where H(u) = (H1(u),⋯, HN(u)) is a function with values in (0, 1)N. Based on some assumptions of H(u), we obtain the existence of the local times of XH(u)(u) and establish its joint continuity and the Holder regularity. These results generalize the corresponding results about fractional stable sheets to multifractional stable sheets.

CO2 sequestration using microalgae has been deemed as a promising way, which can fix CO2 and simultaneously produce valuable bio-products. However, large scale open-pond production of Chlorella vulgaris is normally cultured using acetic acid as a carbon source, which is costly and shows a low efficiency in CO2 fixation. Here, a new mixotrophic culture strategy using both CO2 and acetic acid was developed and evaluated for CO2 sequestration by a C. vulgaris culture in an open pond. Our results show that the growth rate of C. vulgaris under this new mixotrophic condition reaches 0.24 g/L/d, which is higher than the 0.15 and 0.21 g/L/d of photoheterotrophic culture with acetic acids and photoautotrophic culture with CO2, respectively. The averaged CO2 fixation rate was determined as 0.29 g/L/d, which is much higher than heterotrophic method but slightly lower than photoautotrophic method. This result was further confirmed in a 125 m2 open raceway pond. Physiological and biochemical characterization showed that the cell quality of C. vulgaris under mixotrophic conditions is better than those of photoautotrophic method and photoheterotrophic cultures. The enzyme activity assay and transcriptome sequencing analysis revealed that the metabolism of carbohydrates and amino acids was significantly enhanced under mixotrophic condition compared with other groups, which may attribute to the increased biomass and CO2 sequestration of C. vulgaris. Our results suggest that this mixotrophic strategy can be applied in large-scale cultivation of C. vulgaris for biomass production and CO2 sequestration.

Colossal permittivity (CP) materials have great application prospects in electronic devices. However, obtaining a giant dielectric constant, low dielectric loss, and good temperature stability in one phase simultaneously is a challenge. In this work, the colossal permittivity characteristics along with the related mechanism of (Sr, Ta) co-doped TiO2 ceramics were investigated. According to the dielectric analysis, the dielectric properties are significantly improved when Sr and Ta co-doped, where the addition of Sr is responsible for the reduced tan δ, and the addition of Ta is responsible for the improved e′. The enhanced dielectric constant (> 105) with relatively low dielectric loss is obtained in a large substitution range from x = 1 to 7%, and the good frequency and temperature stability are observed in these samples. In addition, the optimum dielectric properties are obtained at x = 0.05, where e′ = 1.86 × 105, tan δ = 0.15. XPS analysis confirms the existence of reduced Ti3+ ions and oxygen vacancies, which may form the highly stable defect clusters. The defect clusters are responsible for the improved dielectric properties in (Sr, Ta) co-doped TiO2 ceramics. Meanwhile, the interfacial polarization is mentioned to explain CP phenomenon of TiO2-based ceramics. This research is conducive to the development and application of TiO2-based new CP materials.

Although electrospun nanofibers have been used to deliver functional genes into cells attached to the surface of the nanofibers, the controllable release of genes from nanofibers and the subsequent gene transfection with high efficiency remain challenging. Herein, photothermally activated electrospun hybrid nanofibers are developed for high-efficiency surface-mediated gene transfection. Nanofibers with a core-sheath structure are fabricated using coaxial electrospinning. Plasmid DNA (pDNA) encoding basic fibroblast growth factor is encapsulated in the fiber core, and gold nanorods with photothermal properties are embedded in the fiber sheath composed of poly(l-lactic acid) and gelatin. The nanofiber mats show excellent and controllable photothermal response under near-infrared irradiation. The permeability of the nanofibers is thereby enhanced to allow the rapid release of pDNA. In addition, transient holes are formed in the membranes of NIH-3T3 fibroblasts attached to the mat, thus facilitating delivery and transfection with pDNA and leading to increased proliferation and migration of the transfected cells in vitro. This work offers a facile and reliable method for the regulation of cell function and cell behavior via localized gene transfection, showing great potential for application in tissue engineering and cell-based therapy.

The decoration of n-type silicon (n-Si) with bimetallic NiFe nanoparticles has been shown to be an effective approach in achieving efficient photoelectrochemical (PEC) water oxidation. However, the...

Single nucleotide polymorphisms (SNPs) have been proven to be important biomarkers for disease diagnosis, prognosis and disease pathogenesis. Here, taking the advantages of a self-assembled oligonucleotide sandwich structure and robust chemical reactions, we have developed a simple, high-throughput and effective colorimetric analytical technique termed CuAAC-based ligation-assisted assays (CuAAC-LA) for SNP detection using a DNA-BIND 96-well plate. With the 5'-azide and 3'-alkyne groups labelled on two oligonucleotide probes, the target DNA can direct a Cu(i)-catalyzed alkyne-azide cycloaddition (CuAAC) click reaction. Since the small difference in duplex stability caused by a single-nucleotide mismatch was amplified by the steric effects of these reactive groups for the ligation reaction of an unstable duplex, CuAAC-LA exhibited an ultra-sensitive discrimination ability for a mutant type target in the presence of large amounts of wild type targets. As low as 0.05% SNP could be clearly detected, which was better than most previously reported methods by various DNA ligases, indicating that a simple and rapid synthetic method i.e., the DNA template-directed click reaction held the potential to replace the ligase for SNP detection.

2,6-Diamino-3,5-dinitropyrazine-1-oxide (LLM-105) is a representative of the new generation of low-sensitivity energetic materials and has been applied extensively in formulations as an insensitive high-energetic ingredient. Although the initial thermal decomposition mechanism of LLM-105 has been studied based on quantum chemical calculations, the internal mechanism of the two-step thermal decomposition still lacks experimental research. Thus, this study involves a detailed experimental study to reveal the mechanism of the two-step thermal decomposition of LLM-105. The results showed that LLM-105 decay was a consecutive reaction. The first-step reaction dominated the early stage of the LLM-105 decomposition, and its products participated in the reaction of the second step. The cleavage of NO2 and NH2 groups of LLM-105 mainly occurred in the first step, while gaseous products NO and C2N2 were released during the second reaction step. The first-step reaction had a higher oxygen consumption rate and a lower carbon consumption rate, producing more heat due to more extensive oxidation of the carbon backbone. The difference in the oxidative ability and reaction rate between the two steps resulted in a two-step exothermic and mass loss behavior. This study provides further insights into the entire reaction process of LLM-105 and would be helpful for its better application and for the design of new explosives.

Early diagnosis and therapy of hepatocellular carcinoma (HCC) is critical to improve the five-year survival rates of patients. Theranostic agents synergized with photothermal ablation are expected to realize the early detection and treatment of orthotopic HCC. However, conventional metallic nanoagents are limited by their potential bio-toxicity to surrounding normal organs. Recently, endogenous biological melanin pigments have been utilized to develop nanoplatforms due to their excellent biocompatibility and degradability. Whereas, the insufficient capability of PEGylated melanin nanoparticles (PEG-MNPs) in photoacoustic (PA) imaging limits their further biomedical applications. Paradoxically, it is difficult to meet these two different requirements. Herein, a multifunctional nanoagent based on melanin (MNPs) conjugating the near-infrared (NIR) dye IR820 was successfully designed and fabricated. Encapsulation by polyethylene glycol (PEG) renders the solubility in water and allows the physical absorption of IR820 for enhanced photoacoustic (PA) performance and photothermal therapy. Besides, PEG coating on the surface of IR820-PEG-MNPs resulted in a reduction in swallowing in the reticuloendothelial system of the liver and spleen, prolonging the circulation time in the blood and increasing the accumulation in the tumor. The IR820-PEG-MNPs displayed satisfactory PA and T1-weighted magnetic resonance imaging (MRI) signals in aqueous solution as well as strong photothermal efficiency. Compared with prior injection, PA/MR signals of the tumor region were enhanced by 4.13- and 1.60-fold, respectively, which could effectively detect lesions smaller than ∼1.8 mm. Furthermore, the high photothermal conversion efficiency (40.2%) endowed the IR820-PEG-MNPs with the capability of selectively ablating tumors in orthotopic HCC mouse models under the guidance of PA/MR imaging. This work broadens the biomedical applications of melanin-based agent, which are promising for the precise diagnosis of orthotopic micro HCC and imaging guided photothermal ablation.

Oxidation is a universal process causing metals’ corrosion and degradation. While intensive researches have been conducted for decades, the detailed atomistic and mesoscale mechanisms of metal oxidation are still not well understood. Here using in situ environmental transmission electron microscopy (E-TEM) with atomic resolution, we revealed systematically the oxidation mechanisms of aluminum from ambient temperature to ~ 600 °C. It was found that an amorphous oxide layer formed readily once Al was exposed to air at room temperature. At ~ 150 °C, triangle-shaped Al2O3 lamellas grew selectively on gas/solid (oxygen/amorphous oxide layer) interface, however, the thickness of the oxide layer slowly increased mainly due to the inward diffusion of oxygen. As the temperature further increased, partial amorphous-to-crystallization transition was observed on the amorphous oxide film, resulting in the formation of highly dense nano-cracks in the oxide layer. At ~ 600 °C, fast oxidation process was observed. Lamellas grew into terraces on the oxide/gas interface, indicating that the high temperature oxidation is controlled by the outward diffusion of Al. Single or double/multi-layers of oxide nucleated at the corners of the terraces, forming dense γ’-Al2O3, which is a metastable oxide structure but may be stabilized at nanoscale.

This paper deals with extensions of free sets over commutative semirings. First, we discuss a necessary and sufficient condition that a finitely generated L-semimodule is free, and by the way, we g...

Metal-Organic Frameworks (MOFs) have aroused great interest in the field of nanoscience and nanotechnology particularly in biomedical domains, such as Drug Delivery System (DDS), Biomedical Imaging (BI) and Photodynamic Therapy (PDT). As an emerging material, MOFs possess extraordinarily high surface area, controllable particle size and good biocompatibility. With extraordinary flexibility in the selection of organic and inorganic components, MOFs can rationally be tuned to obtain the materials having versatile structures and porosities. MOFs can serve as ideal vehicles for DDS, BI and PDT through modification and function. In this review, we summarized the design and synthetic strategies for preparing MOFs and introduced their recent advanced usage in DDS, BI and PDT. Finally, the prospect and future challenges of these nanomaterials are also documented.

The detection of cancer micrometastasis for early diagnosis and treatment poses a great challenge for conventional imaging techniques. The aim of our study was to evaluate the performance of photoacoustic imaging (PAI) in detecting hepatic micrometastases from melanoma at a very early stage and in aiding tumor resection by intraoperative guidance. Methods: In vivo studies were performed by following protocols approved by the Ethical Committee for Animal Research at Xiamen University. First, a mouse model of B16 melanoma metastatic to the liver (n = 10) was established to study the development of micrometastases in vivo. Next, the mice were imaged by a scalable PAI instrument, ultrasound, 9.4-T high-resolution MRI, PET/CT, and bioluminescence imaging. PAI scans acquired with optical wavelengths of 680–850 nm were kept spectrally unmixed by using a linear least-squares method to differentiate various components. Differences in signal-to-background ratios among different modalities were determined with the 2-tailed paired t test. The diagnostic results were assessed with histologic examination. Excised liver samples from patients diagnosed with hepatic cancer were also examined to identify the tumor boundaries. Surgical removal of metastatic melanoma was precisely guided in vivo by the portable PAI system. Results: PAI was able to detect metastases as small as approximately 400 μm at a depth of up to 7 mm in vivo—a size that is smaller than can be detected with ultrasound and MRI. The tumor-to-liver ratio for PAI at 8 d (4.2 ± 0.2, n = 6) and 14 d (9.2 ± 0.4, n = 5) was significantly higher than for PET/CT (1.8 ± 0.1, n = 5, and 4.5 ± 0.2, n = 5, respectively; P < 0.001 for both). Functional PAI revealed dynamic oxygen saturation changes during tumor growth. The limit of detection was approximately 219 cells/μL in vitro. We successfully performed intraoperative PAI-guided surgery in vivo using the portable PAI system. Conclusion: Our findings offer a rapid and effective complementary clinical imaging application to noninvasively detect micrometastases and guide intraoperative resection.

The construction of a smart city puts forward new requirements for lighting systems, such as variable color temperature adapting to environment and low energy consumption. We introduce a variable color temperature laser lighting system that produces uniform light with minimum energy. The color temperature is controlled by tri-color RGB diode lasers, and uniform lighting is achieved by microlens arrays. Tri-color diode lasers with wavelengths of 650, 556, and 450 nm are used as the lighting sources, and the white light laser output is achieved by combining the three beams. The color temperature is controlled by changing the power ratio of each lighting source. Finally, the homogenization of laser energy is regulated by the microlens arrays, and the energy uniformity reaches 91.1%. Moreover, we do an experiment to compare LED street lighting and laser street lighting, finding that the street lighting system with this design can increase the energy utilization rate by 113.33%, and the color temperature of the car headlamps with this design can be changed according to the environment. Therefore, this laser lighting system is an effective solution for modern smart lighting systems and energy saving, which have vast application.

The estimation accuracy of tidal harmonic constants is of great significance to maritime traffic and port construction. However, due to the long sampling period of satellite altimeters, tidal signals alias the mesoscale ocean frequencies. As a result, the harmonic analysis is affected by mesoscale environmental noise. In this study, the influence of the mesoscale ocean variability (MOV) on the estimation of tidal harmonic constants was quantified by analyzing 25 years of altimeter data from the Topex/Poseidon (T/P) and Jason satellites in the South China Sea (SCS). The results indicated that the absolute amplitude differences (AADs) of the eight major tidal constituents before and after the mesoscale variability correction (MVC) were generally within 10 mm, and most were within 6 mm. For the relative impact, M2, O1, and K1 were not obviously affected by the MOV because of their large amplitudes, and the AADs generally accounted for less than ±10% of the amplitudes. As a tidal constituent with amplitude less than 2 cm in the SCS, the amplitude of K2 was significantly affected by the MOV, with the ratios of the AADs to its own amplitudes ranging from −64.79% to 95.99% in space. In terms of phase, the K2 tide was most affected by the MOV: 63% of the data points before and after correction were over ±5°, and the maximum and minimum values were 86.46° and −176.27°, respectively. The absolute phase differences of other tidal constituents before and after the MVC were generally concentrated within ±5°. The impact of the MOV on the evolution of tidal amplitudes in the SCS was also explored. It was found that the MOV can cause pseudo-rapid temporal variations of tidal amplitudes in some regions of the SCS.

Salicylic acid (SA) is the phytohormone responsible for the regulation of growth and response to environmental stress in plants. In the present study, the application of 1 μM SA significantly enhanced the SA content in rice roots and improved their growth when affected by Al toxicity by concomitantly decreasing the Al content of the root apex. The addition of SA significantly inhibited the synthesis of pectin and hemicellulose, suppressed the activity of pectin methylesterase (PME), and decreased the cell wall Al content. The expression of OsSTAR1 (sensitive to Al rhizotoxicity) and OsSTAR2 was induced by SA to mask the Al-binding sites in the cell walls. The expression of OsALS1 (Al sensitive) was also stimulated by SA, which improved the transport of cytoplasmic Al into the vacuoles. In rice affected by Al toxicity, SA significantly increased the activity of catalase and peroxidase and reduced the H2O2 content and malondialdehyde content. The expression of OsACS1 (ACC synthase) and OsACO1 (ACC oxidase) was inhibited by SA and thus inhibited ethylene emission. The addition of ethylene precursor 1-aminocylopropane-1-carboxylic acid (ACC) along with SA under Al toxicity conditions aggravated the inhibition of root elongation, accompanied by an increased Al content in the root apex and cell walls, increased pectin content, and rendered PME activity greater than with single Al treatment. However, the addition of aminoethoxyvinylglycine (AVG, inhibitor of the ACC synthase) along with SA under Al toxicity conditions showed the opposite effect, indicating that SA inhibited ethylene emission, thus reducing the Al deposition on cell walls.

We deal with the least squares estimator for the drift parameters of an Ornstein-Uhlenbeck process with periodic mean function driven by fractional Levy process. For this estimator, we obtain consistency and the asymptotic distribution. Compared with fractional Ornstein-Uhlenbeck and Ornstein-Uhlenbeck driven by Levy process, they can be regarded both as a Levy generalization of fractional Brownian motion and a fractional generalization of Levy process.

The first, third and fifth members (henceforth referred to as T 3 x 1 , T 3 x 3 and T 3 x 5 , respectively) of the Upper Triassic coal-bearing Xujiahe Formation black shale are among the most significant hydrocarbon source rocks in the Sichuan basin. Here, we present geochemical data for the Upper Triassic black shales from core from Well LD-1 to determine their paleoenvironmental conditions, paleoweathering, provenance transitions and tectonic setting. The V/(V + Ni) vs. U/Th, V/Cr vs. U/Th and Ni/Co vs. U/Th bivariate plots and the TFe-TOC-TS (total Fe-total organic carbon-total Sulphur) ternary diagram indicate that the synsedimentary redox regime of almost all the shale samples was oxidizing. Ba/Al, Sr/Al and P/Ti data combined with quantitative biogenic Ba data indicate that moderate-high primary paleoproductivity levels prevailed during deposition. The Sr/Cu ratio and C-value combined with the sedimentary features are indicative of warm-humid climate conditions. The Ti/Al deposition rate proxy and decompacted sedimentation rate are positively correlated with the total organic carbon (TOC) content. According to our multiproxy approach, black shale development in the Xujiahe Formation was mainly controlled by the primary productivity level, foreland basin setting, high tectonic subsidence and sedimentation rate and exhibited a limited correlation with water column redox conditions. Through the compilation and calculation of various weathering indices for the Xujiahe black shale, we suggest that caution must be taken when inferring paleoclimate characteristics based on the chemical index of alteration (CIA) because of the influence of multiple nonweathering factors. Provenance-sensitive elemental ratios (Th/Sc vs. Zr/Sc and Co/Th vs. La/Sc) indicate that the clastic contribution to Xujiahe black shales was of a predominantly felsic character. The black shales exhibit a transition from T 3 x 1 to T 3 x 3 to T 3 x 5 , whereby T 3 x 1 was primarily sourced from the Proterozoic to early Paleozoic strata of the Qinling orogeny, T 3 x 3 was primarily sourced from the Neoproterozoic complex in the Longmen Shan, and T 3 x 5 was primarily sourced from the Songpan-Ganzi flysch strata, which contributed recycled material because of folding and strong southeastward thrusting.

Under certain mild conditions, some limit theorems for functionals of two independent Gaussian processes are obtained. The results apply to general Gaussian processes including fractional Brownian motion, sub-fractional Brownian motion and bi-fractional Brownian motion. A new and interesting phenomenon is that, in comparison with the results for fractional Brownian motion, extra randomness appears in the limiting distributions for Gaussian processes with nonstationary increments, say sub-fractional Brownian motion and bi-fractional Brownian. The results are obtained based on the method of moments, in which Fourier analysis, the chaining argument introduced in [11] and a pairing technique are employed.

High-entropy alloys are a class of materials that contain five or more elements in near-equiatomic proportions1,2. Their unconventional compositions and chemical structures hold promise for achieving unprecedented combinations of mechanical properties3–8. Rational design of such alloys hinges on an understanding of the composition–structure–property relationships in a near-infinite compositional space9,10. Here we use atomic-resolution chemical mapping to reveal the element distribution of the widely studied face-centred cubic CrMnFeCoNi Cantor alloy2 and of a new face-centred cubic alloy, CrFeCoNiPd. In the Cantor alloy, the distribution of the five constituent elements is relatively random and uniform. By contrast, in the CrFeCoNiPd alloy, in which the palladium atoms have a markedly different atomic size and electronegativity from the other elements, the homogeneity decreases considerably; all five elements tend to show greater aggregation, with a wavelength of incipient concentration waves11,12 as small as 1 to 3 nanometres. The resulting nanoscale alternating tensile and compressive strain fields lead to considerable resistance to dislocation glide. In situ transmission electron microscopy during straining experiments reveals massive dislocation cross-slip from the early stage of plastic deformation, resulting in strong dislocation interactions between multiple slip systems. These deformation mechanisms in the CrFeCoNiPd alloy, which differ markedly from those in the Cantor alloy and other face-centred cubic high-entropy alloys, are promoted by pronounced fluctuations in composition and an increase in stacking-fault energy, leading to higher yield strength without compromising strain hardening and tensile ductility. Mapping atomic-scale element distributions opens opportunities for understanding chemical structures and thus providing a basis for tuning composition and atomic configurations to obtain outstanding mechanical properties. In high-entropy alloys, atomic-resolution chemical mapping shows that swapping some of the atoms for larger, more electronegative elements results in atomic-scale modulations that produce higher yield strength, excellent strain hardening and ductility.

Vacuum adsorption was employed to synthesize platinum/polyethylene terephthalate (PET) samples with great potential for indoor air quality improvement application. Pt nanoparticles (PNPS) were loaded onto surface of non-woven fabric composed of polyethylene terephthalate (PET) and with high air permeability. High activity was sought for the Pt/PET catalyst by investigating the effects of hexadecyl trimethyl ammonium bromide (CTAB) on PNP sizes and PET fiber surfaces. The prepared samples were characterized by XRD, SEM, TEM, TG, FTIR and XPS analysis. The results indicated that Pt/PET samples were successfully fabricated, and a formaldehyde conversation of 70.8 % was obtained within 150 min at 35 °C using Pt/PET with 0.6 wt% Pt loading. This research provided a facile method for depositing Pt onto PET fibers (non-woven fabric), and the catalytic activities of the resulting composite Pt/PET materials indicated them to be promising for applications to indoor air remediation.

Tyrosyl-DNA phosphodiesterase 1 (TDP1) is a recently discovered enzyme specifically repairing DNA topoisomerase IB-mediated DNA damage, and is a rational anticancer target. Herein, we report the design and synthesis of the first small fluorescent probe 1 as TDP1 substrate. Probe 1 is a specific substrate of TDP1 and shows good spectroscopic properties with more than 140-fold fluorescence enhancement. A novel TDP1 inhibition assay was established using 1 as substrate. The possible cleavage pathway of 1 by TDP1 was also studied.

Graphene/sulfur composite has been extensively studied for sulfur cathodes. However, a rapid and scalable fabrication of sulfur/graphene composite with advanced structures and functions is still a big challenge. Here, we report a unique solution-based strategy to simultaneously realize the reduction of graphene oxide (GO), the synthesis of elemental sulfur (S) and the effective packaging of S. In this strategy, the S firstly reacts with hydrazine hydrate and N, N-Dimethylformamide mixture, which generates a reductive sulfur-containing compound. When mixing this reductive sulfur-containing compound with GO dispersion, GO will be reduced and the reductive sulfur-containing compound will be oxidized to generate S. At the same time S will be well encapsulated inside highly wrinkled graphene layers because of the great interaction between graphene and sulfur through this method. Benefited from the unique packaging structures, the sulfur cathode demonstrates superior electrochemical performance in specific capacity, rate capability and cycling stability. A record high specific capacity of 705 mA h/g is realized at 2C even for a thick sulfur cathode with an areal density of 8.1 mg cm−2. This study brings a facile strategy for the fabrication of advanced sulfur/graphene composites with high energy and power densities.

Remote sensing is a powerful method for mapping soil properties, such as soil organic carbon (SOC), a key property of soil quality. Spectral remote sensing indices that rely on shortwave-infrared (SWIR) or near-infrared (NIR) wavelengths have been developed to quantify spatial patterns in SOC. However, the application of SWIR- and NIR-based indices for quantifying fine-scale patterns of SOC is limited due to the requirement of high-resolution multispectral or hyperspectral imagery. Visible wavelengths are measured by virtually all sensors, often at high resolution; hence, development of a visible wavelength–based index can greatly increase the ability to remotely estimate SOC. Here we develop such an index by assessing the relationship between laboratory-measured SOC and spectral reflectance using 7916 SOC and hyperspectral measurements from the nationwide USDA Rapid Carbon Assessment. Our new SOC index (SOCI) predicts SOC concentrations for the 7916 samples with a RMSE of 1.5%, which is comparable to predictions from the SWIR/NIR ratio (RMSE = 1.3%) and outperforms the predictions of an index based on NIR and red wavelengths (RMSE = 2.8%). We applied the index to a high-resolution satellite image and tested the ability of the image-based SOCI to predict measured SOC concentrations for a plowed field in Iowa. Regression models with and without local calibration data accurately predict measured SOC, with RMSE values of ∼0.5%. Given the widespread availability of imagery with spectral data in the visible wavelengths, there is potential to use the SOCI to address a range of soil-agronomic problems.

Upper Ordovician (Katian) to Lower Silurian (Rhuddanian) strata in the Middle–Upper Yangtze Block, South China contain extensive chert beds, although the origin of microcrystalline silica in these cherts is largely unknown. In this study, the mineralogy and structure of chert as well as major, trace, and rare earth elements are used to determine the origin of microcrystalline silica in 29 chert samples from Longmaxi Formation (Rhuddanian) in Baizitian outcrop, west of Kangdian Uplift (KU). Results show that 21 of the 29 chert samples have a biogenic origin, 2 indicate a hydrothermal origin, and 6 show a mixed origin. Cherts from Baizitian outcrop are compared to contemporaneous cherts deposited east of KU. Cherts both east and west of KU are mainly biogenic in origin, which is attributed to high productivity in the paleo-seaway. Hydrothermal microcrystalline silica is relatively uncommon in the Longmaxi Formation across the Middle-Upper Yangtze Block, and only occurs in Baizitian outcrop. Terrigenous influx contributed to chert accumulation both east and west of KU; however, cherts east of KU received much more clastic material than those in Baizitian outcrop. A comparison of chert composition and geochemistry to geological reconstructions of the Middle-Upper Yangtze Block reveal that accumulation of hydrothermal chert is closely linked to tectonic evolution. During the Early Silurian, the Middle-Upper Yangtze Block was in a compressional tectonic regime with limited heat supply, and hence, low hydrothermal circulation; this is manifested in the paucity of hydrothermal microcrystalline silica in cherts east of KU. In contrast, hydrothermal microcrystalline silica in cherts west of KU is interpreted to have formed in an extensional tectonic regime with sufficient heat supply. This research demonstrates that chert source is, in part, tectonic controlled, and chert geochemistry can be used in reconstructing paleoenvironments.

When boron (B) deficiency and aluminum (Al) toxicity co-exist in acidic soils, crop productivity is limited. In the current study, we found that 3 μM of B pretreatment significantly enhances rice root elongation under Al toxicity conditions. Pretreatment with B significantly decreases the deposition of Al in rice apoplasts, suppresses the synthesis of cell wall pectin, inhibits cell wall pectin methylesterase (PME) activity and its gene expression, and increases the expression of OsSTAR1 and OsSTAR2, which are responsible for reducing the Al content in the cell walls. In addition, B pretreatment significantly increases OsALS1 expression, thereby facilitating the transfer of Al from the cytoplasm to the vacuoles. However, B pretreatment had no effect on Al uptake and citric acid secretion. Pretreatment with B significantly increases the activity of ascorbate peroxidase (APX), peroxidase (POD), and catalase (CAT), thus increasing the elimination rate of H2O2 in rice roots. Co-treatment using B and H2O2 does not increase root growth under Al toxicity conditions; it also improves pectin synthesis, enhances PME activity, and increases Al deposition in root cell walls. However, the co-treatment of B and H2O2 scavenger 4-hydroxy-TEMPO has an opposite effect. The above results indicate that applying B fertilizers in acidic soil can help decrease the side effects of Al toxicity on rice growth.

The Late Ordovician-Early Silurian transition was a critical interval in Earth's history, marked by mass extinction, the Gondwana glaciation and volcanic events. Here, we present mineralogical and geochemical characteristics across the Ordovician-Silurian boundary (Wufeng, Guanyinqiao and Longmaxi formations) from the Huadi No. 1 well, in the Sichuan Basin, in order to explore the paleoweathering, provenance, tectonic setting and paleoclimatic conditions of the source area. Thin sections, XRD (X-ray diffraction) data and major element results reveal that the rocks were abundant in clay minerals, quartz, minor feldspar, pyrite and carbonate minerals. The samples have similar chondrite-normalized REE patterns to those of PAAS, which are characterized by slight LREE enrichments and accompanied by flat HREE trends with weakly negative Eu anomalies. Paleoweathering indices (CIA and PIA) suggest that the sediments experienced weak to moderate chemical weathering in the source area. CIA values in the lower Wufeng formation range from 67.11 to 72.17, indicating a warm and humid climate, the CIA values in the upper Wufeng formation decrease from 70.35 to 66.15, and the CIA values in the Guanyinqiao and lower Longmaxi formation are persistently low (56.64–62.87), suggesting a cold and dry climate, which is consistent with the widespread presence of glaciation in the Hirnantian period. Further upward in the upper Longmaxi formation, the CIA returns to a high value (65.59), which may reflect that the climate started getting warm and glaciation had finished. Fluctuations in CIA values reflect that the climate shifted from warm to cold and then to warm again during the end Ordovician-early Silurian time period. The A-CN-K triangular diagram and SiO2-Al2O3/TiO2, TiO2-Zr, and La/Th-Hf bivariate diagrams indicate that the provenance of the rocks from the three formations was primarily felsic igneous rocks. Discriminant-function diagrams and La-Th-Sc, Th-Co-Zr/10 and Th-Sc-Zr/10 triangular diagrams show that the clastic sediments of the Wufeng-Longmaxi formations were derived most likely from an active continental margin. Finally, across the Late Ordovician-Early Silurian, tectonic activity and the end of the Ordovician glaciation dominantly controlled the deposition of black shales and siltstones in the Wufeng-Longmaxi formations of South China.