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Photoelectrochemical (PEC) water-splitting using solar energy holds great promise for the renewable energy future, and a key challenge in the development of industry viable PEC devices is the unavailability of high-efficient photoanodes. Herein, we designed a TiO2 model photocatalyst with nano-groove pattern and different surface orientation using low-energy Ar+ irradiation and photoetching of TiO2, and significantly improved the intrinsic activity for PEC water oxidation. High-resolution transmission electron microscopy directly manifests that the grooves consist of highly stepped surface with steps and well-crystallized. Transient absorption spectroscopy reveals the groove surface that allows for increased recovery lifetime, which ensures promoted electron-hole separation efficiency. Surface photovoltage directly shows the carrier separation and transportation behaviors, verified by selective photodeposition, demonstrating the groove surface on TiO2 contributes to electron-hole separation. This work proposes an efficient and scalable photoanode strategy, which potentially can open new opportunities for achieving efficient PEC water oxidation performance.

Natural isoquinolinium alkaloids possess a wide range of biological activities. The design and synthesis of mesoionic isoquinoliniums is of great importance. This paper reports the synthesis of unique mesoionic thiazoloisoquinolinium thiolates stabilized by aromatization and 1,3-dipolarization. Such compounds can be synthesized via the three component [2 + 2 + 1] cycloaddition reaction of isoquinolines with ethyl propionate and elemental sulfur in the absence of any metal catalyst and additives. Importantly, thiazoloisoquinolinium thiolates can be transformed to thioether-containing thiazoloisoquinolinium halides. A selective [4 + 2] cycloaddition can also be used to form S-bridged fused tetracyclic compounds with a thiothiamide ring unit and two quarternary carbon centres. Compound I-1 shows good bioactivity against the chlorophyll of duckweed (Lemna minor) with inhibition rate of 51.5 μg/mL.

In this paper, a high-efficiency non-metallic catalyst for the electrocatalytic synthesis of NH3 was prepared by using a sulfur-modified N-doped MOF based on hierarchical porous carbon material. One-pot pyrolysis of metal azolate frameworks (MAF) resulted in the uniform doping of active N precursor. Moreover, the doping of sulfur atoms introduced the synergistic effect and improved the catalytic activity. Furthermore, the formed sulfur was hydrophobic, which hindered the occurrence of HER. Therefore, S/N-MPC achieved a high NH3 yield of 45.51 μgNH3 mgcat.−1 h−1 at −0.3 V and the best FE of 25.16% at −0.2 V, respectively. Moreover, it showed excellent durability in long time electrolysis reaction. Besides, DFT calculation results were used to elucidate the ammonia synthesis pathway of the catalyst, and it was proved that the ammonia synthesis reaction on the catalyst followed the alternate hydrogenation path of the association mechanism.

Recently, atomically dispersed transition-metal single atom in nitrogen-doped carbon matrix as electrocatalysts has aroused general interest. However, there is no report about vanadium single atom for ORR in the literature. According to d-band center theory for transition-metals, the performance of catalysts is regulated by the electronic structure of the catalytic center which determines the intermediate adsorption kinetics. Indeed, the valence of vanadium is variable, its electron structure could be modulated by an appropriate coordination structure. Here, a novel method is developed to prepare the N and O co-coordinated vanadium single atom (V-N1O4) embedded in the carbon matrix. The catalyst displays a half-wave potential of 865 mV in base solution which surpasses 20% Pt/C, and also shows a high power density of 180 mW/cm2 in Zn-air batteries. DFT calculations reveal that the N and O coordination configuration could regulate the electron structure and geometry of vanadium to boost the electrocatalytic activity.

Anthropogenic nitrogen (N) emissions and deposition have been increasing over past decades. However, spatiotemporal variations of N deposition levels and major sources remain unclear in many regions, which hinders making strategies of emission mitigation and evaluating effects of elevated N deposition. By investigating moss N contents and δ15 N values in southwestern (SW) China in 1954-1964, 1970-1994, and 2005-2015, we reconstructed fluxes and source contributions of atmospheric ammonium ( NH4+ ) and nitrate ( NO3- ) deposition and evaluated their historical changes. For urban and non-urban sites, averaged moss N contents did not differ between 1954-1964 and 1970-1994 (1.2%-1.3%) but increased distinctly in 2005-2015 (1.6%-2.3%), and averaged moss δ15 N values decreased from +0.4‰ to +3.3‰ in 1954-1964 to -1.9‰ to -0.7‰ in 1974-1990, and to -4.8‰ to -3.6‰ in 2005-2015. Based on quantitative estimations, N deposition levels from the 1950s to the 2000s did not change in the earlier 20 years but were elevated substantially in the later 30 years. Moreover, the elevation of NH4+ deposition (by 12.2 kg-N/ha/year at urban sites and 4.6 kg-N/ha/year at non-urban sties) was higher than that of NO3- deposition (by 6.0 and 2.9 kg-N/ha/year, respectively) in the later 30 years. This caused a shifted dominance from NO3- to NH4+ in N deposition. Based on isotope source apportionments, contributions of combustion-related NH3 sources (vehicle exhausts, coal combustion, and biomass burning) to the elevation of NH4+ deposition were two times higher than volatilization NH3 sources (wastes and fertilizers) in the later 30 years. Meanwhile, non-fossil fuel NOx sources (biomass burning, microbial N cycles) contributed generally more than fossil fuel NOx sources (vehicle exhausts and coal combustion) to the elevation of NO3- deposition. These results revealed significant contributions of combustion-related NH3 and non-fossil fuel NOx emissions to the historical elevation of N deposition in SW China, which is useful for emission mitigation and ecological effect evaluation of atmospheric N loading.

The complex environment in northern China is the main reason for degradation of expansive mudstone below the canals, which resulted in instability and damage of canal slopes. In this study, a serial of laboratory tests was conducted to explore the volume changes and mechanical behaviors of expansive mudstone below the canals in Xinjiang. The experimental program includes wet-dry (WD) and wet-dry-freeze-thaw (WDFT) tests, volume measurement, and unconfined compression tests. The test results show that during the WD cycles, the volume changes of expansive mudstones with a higher dry range would be more significant. The freeze-thaw process in the WDFT cycles resulted in a decrease of volume change ranges when the expansive mudstones had a relatively smaller dry range and a slight increase of volume change ranges when the expansive mudstones had a relatively larger dry range. In the meantime, the stress-strain relationships of expansive mudstones with different dry ranges all presented strain softening under the cycles of WD or WDFT. The first cycle resulted in a significant decrease of failure strength. After seven WD/WDFT cycles, the failure strength of expansive mudstones with different dry ranges decreased by 37.2%∼59.1%. In addition, the freeze-thaw process in the WDFT cycles promoted the softening of the stress-strain relationships and aggravated the failure strength attenuation of expansive mudstones. Through this study, we expect to provide a preliminary basis for the construction and maintenance of expansive mudstone canals in Xinjiang.

A controlled wrinkled structure is a simple and effective approach to achieve unique properties and has been widely used in flexible materials. In this study, we reported a substrate prestrain method for fabricating wrinkle-structured Zr52Ti34Nb14 multiple-basis-element (MBE) alloy films as biocompatible materials. Variations in the film thickness and substrate prestraining enabled a precise control of the amplitude and wavelength of the wrinkled structures, ranging from micrometers to nanometers. Moreover, owing to the flexibility of the wrinkled structures, the wrinkle-structure pattern could be adjusted by simply relaxing or further stretching of the substrate, leading to dynamically tunable transmittance and wetting behaviors. This result not only reveals Zr52Ti34Nb14 MBE alloy films as a potential flexible material, but also provides a new structural design approach for other MBE alloy systems.

Two-dimensional (2D) MXenes, including carbides, nitrides, and carbonitrides MXene, have been proved to be a possible candidate as anode materials of sodium-ion batteries. This paper focuses on the electronic properties and the electrochemical performance of nitrides MXene. First, density functional theory simulations were utilized to disclose the geometric structure and electronic properties, Na diffusion path, and storage behaviors of titanium carbonitrides Ti3CNTx, nitrides MXene Ti3N2Tx, and carbides MXene Ti3C2Tx with oxygen terminations, predicting the more excellent performance of Ti3N2O2 than Ti3C2O2. Also, then the structure characterization and electrochemical performance experiments of Ti3C2Tx and Ti3CNTx were conducted to verify the theoretical predictions and test the cycling performances. The superior performance of Ti3N2O2 originates from the stronger connection of O-Ti-N than that of O-Ti-C, resulting in the stackings of Ti3N2O2 being tighter and the interlayer spacings being larger than that of Ti3C2O2, which is advantageous to sodiation and desodiation. The capacity of Ti3CNTx increased again to 145 mAh/g after 35 cycles at a current density of 20 mA/g, which demonstrated a better rate performance than Ti3C2Tx corroborated by the diffusion barriers of the theoretical calculation results. Ti3CNTx exhibits a good cycling performance of 110 mAh/g (≈60% of the initial value) after 200 cycles, which is better than that of 87 mAh/g (≈51% of the initial value) of Ti3C2Tx. It is worth noting that all these performances ensure that nitride MXene is more suitable as the anode material of Na-ion batteries than carbide MXene. These findings are conducive to expanding the MXene family and promoting their application in energy storage applications.

Seepage is one of the main causes for the deformation and instability of canal slopes in Xinjiang, China. In this study, centrifugal model tests under wetting-drying (WD) and wetting-drying-freezing-thawing (WDFT) cycles were performed to investigate the water infiltration characteristics below a canal. The results show that the shallow soil of the canal models was fully saturated in the wetting process. Compared with the canal model under the WD cycles, the canal model under the WDFT cycles had larger saturated areas and a higher degree of saturation below the canal top after each cycle, indicating that the freezing-thawing (FT) process in the WDFT cycles promoted the water infiltration behavior below the canal slope. The cracks on the surface of the canal model under the cyclic action of WDFT developed further and had a higher connectivity, which provided the conditions for slope instability from a transverse tensile crack running through the canal top. On this basis, a field test was conducted to understand the water infiltration distribution below a typical canal in Xinjiang, China, which also verified the accuracy of the centrifugal results. This study provides a preliminary basis for the maintenance and seepage treatment of canals in Xinjiang, China.

Large amounts of solid wastes are produced in copper and aluminum smelting processes, which not only cause losses of valuable resources but also threaten the ecology and environment. In this study, a reduction–sulfurization smelting method was used for recovering Cu and Co from converter slags by using spent pot lining (SPL) as the reductant. CaO was added to fix the fluorine from SPL into the cleaned slag. Thermodynamic analysis and experiments were performed to verify the feasibility and determine the optimal conditions of this smelting process. The optimum reductant addition of spent cathode carbon block (SCCB) and spent SiC side block (SSCB) was 8–12 wt %, and the copper and cobalt recovery reached more than 98 and 96%, respectively. The addition of 10 wt % CaO for SCCB improved slag viscosity and promoted the separation between slag and matte/alloy and fixed fluorine in the cleaned slag in the form of insoluble calcium fluoride. The metallized Cu–Co matte was obtained, in which Cu mainly existed in the form of sulfide and Co mainly existed in the form of an iron cobalt alloy.

The amphiphilic humic acid ester ether (HAEE), as a kind of solid-phase extractant with characteristics of easy separation and hydrophilic-hydrophobic amphiphilic property, was prepared and used to extract micro or trace nitrofen, 2,4-dichlorophenol and p-nitrotrophenol (NIPs) from water and soil. Degradation of NIPs and extractant regeneration were carried out by simple photocatalysis. The adsorption equilibrium of the mono- or three mixed NIPs by HAEE in aqueous could be quickly reached within 20 min. The adsorption process was fit to quasi-second-order kinetics model and Friendlich thermodynamics model. The possible adsorption interaction was discussed. Results suggested that the adsorption of NIPs onto HAEE predominated by hydrogen bonding, hydrophobic interaction and π-π interaction. The extraction capacity of mixed NIPs (80 μg/L each component) by HAEE was up to 0.38 mg/g and tended to be multi-layer adsorption, in which p-nitrotrophenol had higher adsorption competitiveness because of lower resistance to HAEE. When HAEE-NIPs were degraded by photo-catalyst Fe

We report the characterization of the channel mobility properties of metal-oxide-semiconductor field-effect transistors (MOSFETs) on the heterogeneous $\beta $ -Ga2O3-on-SiC (GaOSiC) substrate fabricated by an ion-cutting process. The mobility of GaOSiC MOSFETs is significantly improved as the postannealing temperature of Ga2O3 channel increases from 900 °C to 1200 °C. The GaOSiC transistor annealed at 1200 °C exhibits mobility consistent with the $\beta $ -Ga2O3 donor wafer, which suggests that the defects in Ga2O3 channel induced by the H+ implantation for the ion-cutting step can be eliminated by the high-temperature annealing. As the ambient temperature ( ${T} _{{\mathrm {amb}}}$ ) increases from 0 °C to 150 °C, the mobility within the accumulation regime of GaOSiC MOSFETs decreases with the temperature following a ${T}_{{\mathrm {amb}}}^{-1}$ law, which is limited by the phonon scattering. The results of this work will be critically important for designing the transport properties of the GaOSiC channel, significantly advancing the development of Ga2O3 power devices on high thermal conductivity substrate.

The bastnaesite used in hydrometallurgy usually contains 7%–11% fluorine, and the conversion of fluorine into high-value products is the key to achieving green production of rare earths and improving the comprehensive utilization of bastnaesite. In order to recover fluorine from bastnaesite in the form of KBF4, the mechanism of F− conversion to BF 4 − in sulphuric acid leaching solution of roasted bastnaesite was studied by using Eh–pH diagram and simulation experiment. It shows that the formation of BF 4 − is affected by pH in the absence of rare earths. BF 4 − is hydrolyzed to BF3OH− and F− when the pH is greater than 3.9, and part of F− exists as HF 2 − when pH is lower than 2. In the presence of La3+, the formation of BF 4 − is mainly affected by LaF3 when pH is greater than 0, and in the case that the pH is lower than 2, it is mainly affected by HF 2 − . When Ce4+ is present in solution, CeF 2 2 + can exist stably in sulphuric acid solution. Bringing down the pH can reduce the stability of CeF 2 2 + and increase the BF 4 − conversion rate. Based on these results, KBF4 was prepared in the alkaline solution of bastnaesite, and the conversion of BF 4 − is 84.31%. This provides a theoretical basis for the recovery of fluorine from bastnaesite in the form of KBF4.

House price prediction is a popular topic, and research teams are increasingly performing related studies by using deep learning or machine learning models. However, because some studies have not considered comprehensive information that affects house prices, prediction results are not always sufficiently precise. Therefore, we propose an end to end joint self-attention model for house prediction. In this model, we import data on public facilities such as parks, schools, and mass rapid transit stations to represent the availability of amenities, and we use satellite maps to analyze the environment surrounding houses. We adopt attention mechanisms, which are widely used in image, speech, and translation tasks, to identify crucial features that are considered by prospective house buyers. The model can automatically assign weights when given transaction data. Our proposed model differs from self-attention models because it considers the interaction between two different features to learn the complicated relationship between features in order to increase prediction precision. We conduct experiments to demonstrate the performance of the model. Experimental data include actual selling prices in real estate transaction data for the period from 2017 to 2018, public facility data acquired from the Taipei and New Taipei governments, and satellite maps crawled using the Google Maps application programming interface. We utilize these datasets to train our proposed and compare its performance with that of other machine learning-based models such as Extreme Gradient Boosting and Light Gradient Boosted Machine, deep learning, and several attention models. The experimental results indicate that the proposed model achieves a low prediction error and outperforms the other models. To the best of our knowledge, we are the first research to incorporate attention mechanism and STN network to conduct house price prediction.

SARS-CoV-2 is the pathogen responsible for the COVID-19 pandemic. The SARS-CoV-2 papain-like cysteine protease (PLpro) has been implicated in playing important roles in virus maturation, dysregulation of host inflammation, and antiviral immune responses. The multiple functions of PLpro render it a promising drug target. Therefore, we screened a library of approved drugs and also examined available inhibitors against PLpro. Inhibitor GRL0617 showed a promising in vitro IC50 of 2.1 μM and an effective antiviral inhibition in cell-based assays. The co-crystal structure of SARS-CoV-2 PLproC111S in complex with GRL0617 indicates that GRL0617 is a non-covalent inhibitor and it resides in the ubiquitin-specific proteases (USP) domain of PLpro. NMR data indicate that GRL0617 blocks the binding of ISG15 C-terminus to PLpro. Using truncated ISG15 mutants, we show that the C-terminus of ISG15 plays a dominant role in binding PLpro. Structural analysis reveals that the ISG15 C-terminus binding pocket in PLpro contributes a disproportionately large portion of binding energy, thus this pocket is a hot spot for antiviral drug discovery targeting PLpro., The SARS-CoV-2 papain-like protease (PLpro) is of interest as a drug target. Here, the authors identify GRL0617 as a PPI (protein–protein interaction) inhibitor of SARS-CoV-2 PLpro that inhibits its deISGylating activity and present the mechanism of action of the compound through the GRL0617-bound PLpro crystal structure and NMR studies.

We propose and design a hollow As2S3 ring-core photonic crystal fiber (PCF) with 514 radially fundamental orbital angular momentum (OAM) modes over 360 nm communications bandwidth across all the O, E, S, C, and L bands. The designed PCF with 40 $\mu \text{m}$ -radius air core and 150 nm-width As2S3 ring can support eigenmodes up to HE130,1 and EH128,1. The numerical analysis shows that the designed ring PCF has large effective refractive index contrast, and can transmit up to 874 OAM modes near 1.55 $\mu \text{m}$ . Simulation results show that in the C and L bands, the PCF with a hollow-core radius of 40 $\mu \text{m}$ and a ring width of 0.15 $\mu \text{m}$ can retain an $2.5\times 10 ^{-3}$ effective refractive index difference between the two highest order OAM modes, which achieves effective mode separation, thereby achieving stable OAM mode transmission. The $n_{eff}$ difference between the even and odd fiber eigenmodes and the intra-mode walk-off are also carefully studied under different bending radii. The results show that higher-order OAM modes has better tolerance to the fiber bending, compared with the lower-order modes. The fiber has the potential to support ultra-high capacity OAM mode division multiplexing in the optical fiber communication systems.

Dual graphite batteries (DGBs) employ graphite as an intercalation host and store energy using the redox reactions of ionic liquid electrolyte-derived ions with graphite electrodes. As bulky (e.g., imidazolium-based) cation intercalation into the negative graphite electrode may cause its deterioration and thus aggravate self-discharge behaviour, a deep mechanistic understanding of such intercalation is required to enhance the DGB performance; however, the related studies remain scarce. Herein, the intercalation of 1,2-dimethyl-3-propylimidazolium (DMPI+) cations into the negative graphite electrode is probed by in situ X-ray diffraction and in situ Raman spectroscopy. The results show that these cations are stored in the shallow surface layer of bulk graphite without dramatic expansion into the deep graphite lattice, in stark contrast to the intercalation of AlCl4− counter-anions into the positive graphite electrode. Further analysis reveals that DMPI+ storage kinetics can be described as intercalation pseudocapacitance dominated, while first-principles calculations show that intercalation is thermodynamically more favourable than surface adsorption. Although only the DMPI+ cation is studied herein, the obtained insights are expected to be extendable to other bulky cations (e.g., pyrrolidinium or piperidinium). In addition, this study deepens our understanding of factors influencing the performance of DGBs with ionic liquid electrolytes and promotes the further development of energy storage systems with greater power and energy densities.

Taking advantage of the state-of-the-art graphene preparation technologies in China and abroad, this work studied the preparation processes of graphene for road applications based on the preliminary high-speed vibration ball milling method. This work combined numerical modeling and microscopic experiments. The preparation parameters were optimized through a multifactor and multilevel test scheme. The materials, influencing factors, and parameters in the preparation process were systematically studied. A graphene preparation method was proposed that considered vibration frequency, static filling rate, material-to-ball volume ratio, and the void percentages of media. Flake graphite, aluminum powder, and 304 stainless-steel grit were used as the preparation materials. The preparation parameters and process model were established based on the uniform design method. The preparation parameters were proposed, calculated, and optimized. Microscopic analysis showed that the proposed preparation method can improve the quality of graphene. This study provides a new source of raw materials for the application of graphene in road engineering.

Targeted proteomics has advantages over earlier conventional technologies for protein detection. We developed and validated an LC/MRM-MS-based targeted proteomic method combined with immunoaffinity precipitation for the enrichment and detection of low abundance chemerin isoforms in human biofluids. After tryptic digestion, each chemerin isoform was characterized by isoform-specific peptides, and the absolute quantification was achieved by using stable isotope-labeled peptides as internal standards. In serum, follicular fluid and synovial fluid, a total of 6 chemerin isoforms were identified and quantified, among which a novel natural isoform 153Q was discovered for the first time. The relative content of the six chemerin isoforms in human serum was 157S ≫ 156F ≫ 158K > 154F ≥ 155A > 153Q in the ratio of 25:17:5:2.5:2.2:1, respectively. The absolute contents were in the range of 88–3.5 ng/mL. This distribution remained consistent among the 3 biofluids analyzed. Total chemerin were found to be increased in both polycystic ovary syndrome (serum and follicular fluid) and rheumatoid arthritis (serum) patients. However, chemerin isoform analysis revealed that only 156F & 157S were increased in the former, while 155A, 156F & 157S were increased in the latter. This demonstrates the potential of this method in detailed characterization of changes in chemerin isoforms that may be of clinical relevance.

Certain tephritid fruit flies, such as the oriental fruit fly, Bactrocera dorsalis , the Chinese citrus fly, B. minax and the Japanese orange fly, B. tsuneonis (Diptera: Tephritidae: Dacinae), are destructive citrus pests in China. A two-year trapping study was conducted in pomelo, Citrus maxima, groves in Fujian Province of China. The objectives of this study were to investigate the species, the abundance of tephritid fruit flies in the orchards, as well as the efficacy of the selected lure traps to these flies. Four lure traps or devices, i.e. methyl eugenol + Steiner trap (ST), cuelure + ST, ammonium acetate + putrescine + ST, and sticky spheres, were deployed from June to November 2017 and April to October 2018. Six economically significant Dacini pests were trapped during the period. These flies are B. dorsalis, the melon fruit fly, Zeugodacus cucurbitae, the pumpkin fruit fly, Z. tau, the Malaysian fruit fly, B. latifrons, and other two species - B. rubigina and Z. scutellatus. B. dorsalis was the most abundant, accounting for more than 50% of the capture, followed by Z. cucurbitae. The remaining four species accounted for less than 2% of the total capture. B. minax and B. tsuneonis, two destructive citrus-damaging tephritid fruit flies in China, were not found during the trapping period. Methyl eugenol trapped the highest number of fruit flies, followed by cuelure.

Precision agriculture requires new technologies for rapid diagnosis of plant stresses, such as nutrient deficiency and drought, before the onset of visible symptoms and subsequent yield loss. Here, we demonstrate a portable Raman probe that clips around a leaf for rapid, in vivo spectral analysis of plant metabolites including carotenoids and nitrates. We use the leaf-clip Raman sensor for early diagnosis of nitrogen deficiency of the model plant Arabidopsis thaliana as well as two important vegetable crops, Pak Choi (Brassica rapa chinensis) and Choy Sum (Brassica rapa var. parachinensis). In vivo measurements using the portable leaf-clip Raman sensor under full-light growth conditions were consistent with those obtained with a benchtop Raman spectrometer measurements on leaf-sections under laboratory conditions. The portable leaf-clip Raman sensor offers farmers and plant scientists a new precision agriculture tool for early diagnosis and real-time monitoring of plant stresses in field conditions.

A series of Sn–Ti(n)–DETA catalysts were prepared by a simple EISA method assisted by post-treatment of diethylenetriamine (DETA) solution, and several characterization techniques, including XRD, N2 sorption, Raman, ICP, UV–Vis DRS, pyridine-adsorbed IR, SEM, and TEM, were adopted to investigate their physical and chemical properties. The influence of DETA on the tin incorporation promotion of mesoporous Sn–Ti catalysts and their catalytic performance in the B–V oxidation of cyclohexanone by molecular oxygen were also studied. The mesopores with higher surface area and larger pore volume can be kept well when the weight percent of tetrahedrally incorporated tin species would be promoted up to 21% owing to the stronger alkalinity and more primary amine of the DETA molecule resulting in higher Lewis acidity. The cyclohexanone conversion of 95.5% and caprolactone selectivity of 96.8%, respectively, over Sn–Ti(21)–DETA catalyst were obtained, and it shows good catalytic stability even after reused for 5 times.

In this article, we consider testing independence between two spatial Gaussian random fields evaluated, respectively, at p and q locations with sample size n, where both p and q are allowed to be larger than n. We impose no spatial stationarity and no parametric structure for the two random fields. Our approach is based on canonical correlation analysis (CCA). But instead of applying CCA directly to the two random fields, which is not feasible for high-dimensional testing considered, we adopt a dimension-reduction approach using a special class of multiresolution spline basis functions. These functions are ordered in terms of their degrees of smoothness. By projecting the data to the function space spanned by a few leading basis functions, the spatial variation of the data can be effectively preserved. The test statistic is constructed from the first sample canonical correlation coefficient in the projected space and is shown to have an asymptotic Tracy–Widom distribution under the null hypothesis. Our proposed method automatically detects the signal between the two random fields and is designed to handle irregularly spaced data directly. In addition, we show that our test is consistent under mild conditions and provide three simulation experiments to demonstrate its powers. Moreover, we apply our method to investigate whether the precipitation in continental East Africa is related to the sea surface temperature (SST) in the Indian Ocean and whether the precipitation in west Australia is related to the SST in the North Atlantic Ocean.

This work reports an innovative route for biomass upgrading via hydrodeoxygenation (HDO) reactions which avoids external high-pressure hydrogen supply and harsh conditions (such as high-temperature...

Magnetic impurities in metallic superconductors are important for both fundamental and applied sciences. In this study, we focused on dilute Mn-doped aluminum (AlMn) films, which are common superconducting materials used to make transition edge sensors and other superconducting devices. We developed a multi-energy ion-implantation technique to make AlMn films. Compared with frequently used sputtering techniques, ion-implantation provides more precise control of the Mn doping concentration in the AlMn films. It enables us to fabricate reliably AlMn films with a different superconducting transition temperature (Tc) that can match a variety of application needs. We also found that the superconducting transition temperature drops with increasing film thickness for samples with the same nominal concentration of Mn dopants. The dependence of Tc on the film thickness is attributed to the increasing implantation energy. By quantitatively analyzing the curves of Tc versus the Mn doping concentration, we propose that Mn dopants act as magnetic impurities and suppression of superconductivity is counteracted by the antiferromagnetic Ruderman–Kittel–Kasuya–Yosida interaction among Mn dopants, which is influenced by the defects induced in the ion-implantation process.

Four noncovalently fused-ring electron acceptors p-DOC6-2F, o-DOC6-2F, o-DOC8-2F and o-DOC2C6-2F have been designed and synthesized. p-DOC6-2F and o-DOC6-2F have the same molecular backbone but dif...

The gas-liquid two-phase flow field inside a soybean milk machine is simulated with the Navier–Stokes equations, Renormalization group (RNG) k-ɛ turbulence model and the particle two-phase flow model. The critical speed of vortex breakdown in the container and the influence of the characteristics of the two-phase flow on the soybean crushing effect at different speeds are investigated. The results show that there is a critical value of rotating speed of 1500 rpm for the vortex breakdown in the studied machine. At this rotational speed, the turbulent eddy dissipation (TED) reaches the maximum, and the position where the vortex first rupture is near the central axis and with a distance of 0.01 m from the central axis. It is also found that with the increase of rotating speed, the pressure difference around the blade varies significantly. The research in this study has important implication for the design of the soybean milk machine.

Photocatalytic hydrogen evolution is a promising method for converting solar energy into chemical energy. Herein, on the basis of graphitic carbon nitride (g-C3N4) material with alveolate structure prepared via the hard template method, transition-metal cobalt oxide nanoparticles were reasonably introduced, and a highly efficient cobalt oxide composite alveolate g-C3N4 (ACN) photocatalyst was successfully prepared. A series of test methods were used to characterize the structural properties of the prepared samples systematically, and the photocatalytic activity of the catalysts in photocatalytic hydrogen evolution was explored. The composite materials have excellent photocatalytic performance mainly because the synergistic effect of the alveolate structure of ACN provides multiple scattering effects; nitrogen vacancies serves as the centers of photogenerated carrier separation; and cobalt oxides accelerates electron transfer. This study provides a new idea for the design of g–C3N4–based photocatalysts with wide light responses and simple structures.

The fast and accurate hydrogen detection is of great significance to the development of hydrogen energy and related techniques. In this work, a simple and cost-effective dielectrophoresis method was employed for fabricating well-aligned lateral arrays of [001]-oriented orthorhombic MoO3 nanoribbons, which exhibit remarkably accelerated room-temperature sensing performance towards 100 ppm of hydrogen with response and recovery time down to 3 s and 16 s. The study on the hydrogen sensing kinetics suggested that the nanoribbon arrays exhibited much higher initial response rate of 2.067%/s than the randomly arranged samples. Moreover, the contribution from the interface diffusion of the adsorbed surface states to the overall response and recovery process could be effectively suppressed by the well-alignment of the nanoribbons. The results also suggested that the suppression of such nanojunction effect will be more effective for building semiconductor sensors towards hydrogen gas with relatively lower concentrations.

NiS2 has become a research hotspot of anode materials for Na-ion batteries due to its high theoretical specific capacity. However, the volume effect, the dissolution of polysulfide intermediates and the low conductivity during the charge/discharge process lead to the low specific capacity and poor cycling stability. NiS2/rGO nanocomposite was prepared by a facile two-step process: GO was prepared by modified Hummers method, and then NiS2/rGO nanocomposite was synthesized by l -cys assisted hydrothermal method. NiS2/rGO nanocomposite shows excellent cycle performance and rate performance, which could be attributed to the mesoporous structure on the graphene skeleton with high conductivity. Besides, the chemical constraint of a unique S O bond on NiS2 could inhibit the dissolution of intermediates and the loss of irreversible capacity.

In order to improve the accuracy of short-term travel time prediction in an urban road network, a hybrid model for spatio-temporal feature extraction and prediction of urban road network travel time is proposed in this research, which combines empirical dynamic modeling (EDM) and complex networks (CN) with an XGBoost prediction model. Due to the highly nonlinear and dynamic nature of travel time series, it is necessary to consider time dependence and the spatial reliance of travel time series for predicting the travel time of road networks. The dynamic feature of the travel time series can be revealed by the EDM method, a nonlinear approach based on Chaos theory. Further, the spatial characteristic of urban traffic topology can be reflected from the perspective of complex networks. To fully guarantee the reasonability and validity of spatio-temporal features, which are dug by empirical dynamic modeling and complex networks (EDMCN), for urban traffic travel time prediction, an XGBoost prediction model is established for those characteristics. Through the in-depth exploration of the travel time and topology of a particular road network in Guiyang, the EDMCN-XGBoost prediction model’s performance is verified. The results show that, compared with the single XGBoost, autoregressive moving average, artificial neural network, support vector machine, and other models, the proposed EDMCN-XGBoost prediction model presents a better performance in forecasting.

Background Camptothecin (CPT) and matrine (MAT) have potential as botanical pesticides against several pest species. However, the mechanisms of metabolic and physiological changes in pests induced by CPT and MAT are unknown. In this study, a toxicological test, an NMR-based metabolomic study, an enzymatic test, and an RT quantitative PCR (RT-qPCR) experiment were all conducted to examine the effect of CPT and MAT on Spodoptera litura. Results CPT (0.5-1%) exerted high toxicity against larvae of S. litura and caused growth stagnation and high mortality of larvae. A variety of metabolites were significantly influenced by 0.5% CPT, including several energy-related metabolites such as trehalose, lactate, succinate, citrate, malate, and fumarate. In contrast, MAT showed low toxicity against larvae and induced almost no changes in hemolymph metabolites of S. litura. Enzymatic tests showed that trehalase activity was significantly decreased in larvae after feeding with 0.5% CPT. RT-qPCR showed that the transcription levels of alanine aminotransferase, malate dehydrogenase, and isocitrate dehydrogenase were decreased while lactate dehydrogenase was increased in the 0.5% CPT-treated group. Conclusions These data indicate that one of the important mechanisms of CPT against S. litura larvae is via the inhibition of trehalose hydrolysis and glycolysis. Our findings also suggest that CPT exhibits a stronger toxicological effect than MAT against S. litura, which provides basic information for the application of CPT in the control of S. litura or other lepidoptera pests.

The thianthrene S-oxide (TTSO)-mediated site-selective silylation of arenes has been realized via a thianthrenation/Pd-catalyzed silylation sequence. This method features a broad substrate scope and wide functional group tolerance under mild conditions and allows the synthesis of a set of (hetero)arylsilanes with operationally simple manipulations. The application and generality of the approach were further demonstrated by the late-stage functionalization of marketed drugs. This reaction also represents the first example of a Pd-catalyzed silylation reaction of aryl sulfonium salts.

本工作提出了一种插层剂辅助的等离子体液相技术用于高 效地剥离高质量少层二维材料. 采用氯化锂为插层剂可快速剥离 石墨纸, 形成具有小D峰/G峰比(0.02)以及大碳氧比(31.5)的石墨烯 产物. 并且, 这种方法可以拓展至高质量少层2H相二硫化钼的制 备. 和传统的插层剂辅助电化学方法相比, 等离子体诱导产生的大 量活性粒子以及快速的电子转移, 使得插层剂辅助的等离子体液 相技术剥离的产物缺陷少且不会引入额外的基团. 这种可控的快 速剥离方法在制备其他各种类型的高质量二维材料方面都具有巨 大潜力.

The Bambusa oldhamii phenylalanine ammonia-lyase (PAL) proteins, BoPAL1 and BoPAL2, exhibited different substrate specificities toward phenylalanine (Phe) and tyrosine (Tyr). Mutational analysis was conducted to study their substrate selectivity. All expressed wild-type and mutant BoPAL proteins manifested PAL activity; however, Km and kcat values were varied. BoPAL1 F133H and BoPAL2 F134H showed decreased kcat/Km values toward phenylalanine and significantly increased tyrosine ammonia-lyase (TAL) activities. BoPAL1 V197I and BoPAL2 I198 V showed opposite results regarding TAL activity, indicating that the Val or Ile residue prior to the active site, Ala-Ser-Gly, is essential for modulating Phe/Tyr substrate selectivity.

Molybdenum disulfide (MoS2) holds great promise as atomically thin two-dimensional (2D) semiconductor for future electronics and opto-electronics. In this report, we study the magnetoresistance (MR) of MoS2 field-effect transistors (FETs) with graphene insertion layer at the contact interface. Owing to the unique device structure and high-quality contact interface, a gate-tunable linear MR up to 67% is observed at 2 K. By comparing with the MRs of graphene FETs and MoS2 FETs with conventional metal contact, it is found that this unusual MR is most likely to be originated from the contact interfaces between graphene and MoS2, and can be explained by the classical linear MR model caused by spatial fluctuation of carrier mobility. Our study demonstrates large MR responses in MoS2-based systems through heterojunction design, shedding lights for the future magneto-electronics and van der Waals heterostructures.

Diarrhea, as a global public health problem, causes a large number of infections and deaths every year. Although Escherichia coli (E. coli) is one of the normal flora microorganisms in the human intestinal tract, it has five pathogenic bacteria types that can cause human diarrhea, known as diarrheagenic E. coli. When people are infected, rapid and accurate diagnosis, along with timely treatment, are especially important. Here, we introduce a new method to identify and analyze a large number of pathogenic strains in E. coli by multiplex PCR and barcoded magnetic bead hybridization. Results show that the detection sensitivities of enterohemorrhagic E. coli, enterotoxigenic E. coli, enteropathogenic E. coli, enteroinvasive E. coli and enteroaggregative E. coli were 1.3 × 103 CFU/mL, 2 × 104 CFU/mL, 4 × 104 CFU/mL, 7.2 × 104 CFU/mL and 1.7 CFU/mL respectively. This method has strong specificity and high sensitivity and detects multiple target sequences in one experiment. Compared with other methods, BMB array has great application potential.

The attenuation-based rainfall estimator is less sensitive to the variability of raindrop size distributions (DSDs) than conventional radar rainfall estimators. For the attenuation-based quantitative precipitation estimation (QPE), the key is to accurately estimate the horizontal specific attenuation AH, which requires a good estimate of the ray-averaged ratio between AH and specific differential phase KDP, also known as the coefficient α. In this study, a variational approach is proposed to optimize the coefficient α for better estimates of AH and rainfall. The performance of the variational approach is illustrated using observations from an S-band operational weather radar with rigorous quality control in south China, by comparing against the α optimization approach using a slope of differential reflectivity ZDR dependence on horizontal reflectivity factor ZH. Similar to the ZDR-slope approach, the variational approach can obtain the optimized α consistent with the DSD properties of precipitation on a sweep-to-sweep basis. The attenuation-based hourly rainfall estimates using the sweep-averaged α values from these two approaches show comparable accuracy when verified against the gauge measurements. One advantage of the variational approach is its feasibility to optimize α for each radar ray, which mitigates the impact of the azimuthal DSD variabilities on rainfall estimation. It is found that, based on the optimized α for radar rays, the hourly rainfall amounts derived from the variational approach are consistent with gauge measurements, showing lower bias (1.0%), higher correlation coefficient (0.92), and lower root-mean-square error (2.35 mm) than the results based on the sweep-averaged α.

With the aid of a class of newly discovered Trost-type bisphosphine ligands bearing a chiral cycloalkane framework, the Pd-catalyzed decarboxylative dearomative asymmetric allylic alkylation (AAA) of benzofurans was achieved with high efficiency [0.2-1.0 mol% Pd2(dba)3/L], good generality, and high enantioselectivity (>30 examples, 82-99% yield and 90-96% ee). Moreover, a diversity-oriented synthesis (DOS) of previously unreachable flavaglines is disclosed. It features a reliable and scalable sequence of the freshly developed Tsuji-Trost-Stoltz AAA, a Wacker-Grubbs-Stoltz oxidation, an intra-benzoin condensation, and a conjugate addition, which allows the efficient construction of the challenging and compact cyclopenta[b]benzofuran scaffold with contiguous stereocenters. This strategy offers a new avenue for developing flavagline-based drugs.

A new external current sensing circuit with baseline compensation for the active matrix organic light emitting diode (AMOLED) display is developed herein to achieve the sensing precision of 0.5 nA in pixel with 7 µs of settling time. Current sensing circuit incorporates a new push–pull transient current feedforward whereas the current analog to digital converter (CADC) based digital baseline current compensation incorporates an 11-bit current digital-to-analog converter, a current comparator and a digital control circuit with an 11-bit successive approximation register. The proposed integrated mixed signal IC drives a 6T1C pixel-based AMOLED panel with one horizontal time of 7.7 µs at a scan frequency of 60 Hz. The design readout chip can simultaneously sense and compensate TFT baseline current variation. The readout circuit and the baseline compensation circuit are implemented in the integrated chip with chip area of 125 μm × 46 μm and fabricated via TSMC T18 process. With the standard 3.3 V supply, experimental result shows that the overall power consumption of the chip is 988 µW watt. The minimum LSB current for the CADC is 10 nA and the maximum achievable sampling rate is 500 KS/s. The measured INL and DNL of CADC is 0.84 and 0.98 respectively. Despite of heavy data line parasitic capacitances (2.6 KΩ/20 pF) of the AMOLED display, experimental results show that the proposed circuit can sense 0.5 nA current within 7 µs of settling time. The sensing precision of 0.5 nA within 7 µs are the best among all reported literature to date whereas the current sense range (0.5–500 nA), system sampling rate (142 KS/s), INL (0.84) and DNL (0.98) of the CADC is approximately comparable among all reported.

3D-Honeycombed CL-20 structures with low critical size of detonation have been fabricated successfully for intelligent weapon systems using a micro-flow direct ink writing (DIW) technology. The CL-20-based explosive ink for DIW technology was prepared by a two-component adhesive system with waterborne polyurethane (WPU) and ethyl cellulose (EC). Not only the preparation of the explosive ink but also the principle of DIW process have been investigated systematically. The explosive ink displayed strong shear-thinning behavior that permitted layer-by-layer deposition from a fine nozzle onto a substrate to produce complex shapes. The EC content was varied to alter the pore structure distribution and rheological behavior of ink samples after curing. The deposited explosive composite materials are of a honeycombed structure with high porosity, and the pore size distribution increases with the increase of EC content. No phase change was observed during the preparation process. Both WPU and EC show good compatibility with CL-20 particles. Apparently high activation energy was realized in the CL-20-based composite ink compared with that of the refined CL-20 due to the presence of non-energetic but stable WPU. The detonation performance of the composite materials can be precisely controlled by an adjustment in the content of binders. The 3D honeycombed CL-20 structures, which are fabricated by DIW technology, have a very small critical detonation size of less than 69 μm, as demonstrated by wedge shaped charge test. The ink can be used to create 3D structures with complex geometries not possible with traditional manufacturing techniques, which presents a bright future for the development of intelligent weapon systems.

Two-dimensional (2D) materials such as WSe2 are potential for advanced electronics because of their ultra-thin geometry and unique electrical properties. Herein, a simplified high-performance WSe2 complementary inverter based on a buried gate is demonstrated on an individual ambipolar WSe2 flake, in which both n- and p-type WSe2 transistors are achieved by local doping. The n-type doping is induced by the donors of benzyl viologen, showing an electron mobility of 28.1 cm2/V.s. In contrast, the p-type one is realized by Ozone exposure with a high mobility of 36.8 cm2/V.s. The buried gate enables enhanced electrostatic coupling, with a supply voltage (Vdd) of 5 V, and the complementary inverter demonstrates a voltage gain beyond 32, almost ideal noise margin approaching 0.5Vdd and low static power consumption. This work paves the way to achieve high-performance 2D material complementary inverters with simplified fabrication process.

Hyaluronan is widely used in cosmetics and pharmaceutics. Development of robust and safe cell factories and cultivation approaches to efficiently produce hyaluronan is of many interests. Here, we describe the metabolic engineering of Corynebacterium glutamicum and application of a fermentation strategy to manufacture hyaluronan with different molecular weights. C. glutamicum is engineered by combinatorial overexpression of type I hyaluronan synthase, enzymes of intermediate metabolic pathways and attenuation of extracellular polysaccharide biosynthesis. The engineered strain produces 34.2 g L−1 hyaluronan in fed-batch cultures. We find secreted hyaluronan encapsulates C. glutamicum, changes its cell morphology and inhibits metabolism. Disruption of the encapsulation with leech hyaluronidase restores metabolism and leads to hyper hyaluronan productions of 74.1 g L−1. Meanwhile, the molecular weight of hyaluronan is also highly tunable. These results demonstrate combinatorial optimization of cell factories and the extracellular environment is efficacious and likely applicable for the production of other biopolymers., Bioproduction of hyaluronan needs increases in yield and greater diversity of the molecular weights. Here, the author increases hyaluronan production and diversifies the molecular weights through engineering the hyaluronan biosynthesis pathway and disruption of Corynebacterium glutamicum encapsulation caused by secreted hyaluronan.

The improvement of properties of magnetorheological fluids and mechanism study has long been a classic area within the field of magnetorheological materials. This article was undertaken to dope the iron nanoparticles synthesized by direct current electric arc discharge with the traditional carbonyl iron powders to prepare bimodal magnetorheological fluids with different doping ratios. Their rheological properties and sedimentation stability were evaluated to explore the influence rules and mechanisms. The results indicate that the effect of the addition of iron nanoparticles on rheological properties under magnetic field is a combination of two opposing factors such as the strengthening of the structure and the weakening of magnetization. The sedimentation stability of the bimodal magnetorheological fluids improved significantly with the increase in the proportion of iron nanoparticles, which is attributed to the help of both free state and adsorbed state iron nanoparticles in magnetorheological fluids. Furthermore, within a specific magnetic field strength range, the bimodal magnetorheological fluids with a small proportion of iron nanoparticles can achieve an improvement in both rheological property and sedimentation stability compared with carbonyl iron particles–based magnetorheological fluids.

Lead telluride (PbTe) is one of the reliable candidates for infrared (IR) optoelectronics with optimum band-gap as well as excellent photoelectric properties. Great interests had been paid on the growth and device applications with PbTe for the development of high-performance IR photodetectors especially those working in the near-infrared regime. Although a great deal of effort had been made to prepare PbTe nanostructures for miniaturized detectors, it is difficult to synthesize high-quality two-dimensional (2D) PbTe crystals due to its rock-salt non-layered structure. Herein, a facile strategy for controllable synthesis of ultrathin crystalline PbTe nanosheets by van der Waals epitaxy is reported. With an optimized growth temperature, which determines the morphology transit from triangular pyramid islands to regular square 2D planars, PbTe nanosheets in lateral size of tens of microns with thickness down to ~ 7 nm are achieved. Meanwhile, ultrasensitive near-infrared detectors (NIRDs) based on the as-grown 2D PbTe nanosheets have been demonstrated with an ultrahigh responsivity exceeding 3,847 A/W at the wavelength of 1,550 nm under room temperature. Our approach demonstrates that 2D PbTe nanosheets have great latent capacity of developing high-performance miniaturized IR optoelectronic devices.

A transition-metal-free sulfite-promoted three-component C–H sulfuration between imidazoheterocycles, elemental sulfur, and bromofluoroacetate is developed. Sulfites, including Na2S2O4, NaHSO3, and Na2S2O3, are able to promote the formation of two C–S bonds in one step using elemental sulfur as a green sulfurating agent, allowing the rapid introduction of the synthetically useful S-fluoroacetate group into imidazoheterocycles. These new imidazoheterocycle derivatives bearing an S-fluoroacetate group can be easily modified to produce pharmaceutically attractive compounds.

Photocatalytic technology for hydrogen evolution from water splitting and pollutant degradation is one of the most sustainable methods. Here, the graphene/g–C3N4–Co composite materials have been prepared by one-pot calcination method. The results show that g-C3N4 grow on the surface of graphene and form a sandwich structure, meanwhile, the introduction of Co increases the active sites, which promotes the photocatalytic performance. The influences of graphene and Co content on photocatalytic activity were also studied by UV–visible spectrophotometry (DRS), photoluminescence spectroscopy (PL), photocurrent, degradation MB, and hydrogen production. The apparent reaction rate constant k of graphene/g–C3N4–Co (3%) is 0.946 h−1, which is 4.90 and 2.18 times faster than g-C3N4 and graphene/g-C3N4, respectively. And the hydrogen production rate of graphene/g–C3N4–Co (3%) (892.3 μmol h−1 g−1) is 3.53 and 1.61 times higher than g-C3N4 and graphene/g-C3N4, respectively.

In orthotospovirus, the nonstructural protein S (NSs) is the RNA-silencing suppressor (RSS) and pathogenicity determinant. Here, we demonstrate that a putative α-helix, designated H8, spanning amino acids 338 to 369 of the C-terminal region of the NSs protein, is crucial for self-interaction of watermelon silver mottle virus NSs protein and that the H8 affects RSS function. Co-immunoprecipitation, yeast two-hybrid, and bimolecular fluorescence complementation analyses revealed that the triple point mutation (TPM) of H8 amino acids Y338A, H350A, and F353A resulted in NSs protein self-interaction dysfunction. Transient expression of H8-deleted (ΔH8) and TPM NSs proteins in Nicotiana benthamiana plants by agroinfitration indicated that these proteins have weaker RSS activity and are far less stable than wild-type (WT) NSs. However, an electrophoretic mobility assay revealed that small interfering RNA (siRNA) binding ability of TPM NSs protein is not compromised. The pathogenicity assay of WT NSs protein expressed by the attenuated turnip mosaic virus vector restored severe symptoms in recombinant-infected N. benthamiana plants but not for ΔH8 or TPM proteins. Taken together, we conclude that the H8 helix in the C-terminal region of NSs protein is crucial for stabilizing NSs protein through self-interaction to maintain normal functions of RSS and pathogenicity, but not for NSs-siRNA binding activity.

Electrodes based on organic matter operating in aqueous electrolytes enable new approaches and technologies for assembling and utilizing batteries that are difficult to achieve with traditional electrode materials. Here, we report how thiophene‐based trimeric structures with naphthoquinone or hydroquinone redox‐active pendent groups can be processed in solution, deposited, dried and subsequently polymerized in solid state to form conductive (redox) polymer layers without any additives. Such post‐deposition polymerization offers efficient use of material, high mass loading (up to 10 mg cm−2) and good flexibility in the choice of substrate and coating method. By employing these materials as anode and cathode in an acidic aqueous electrolyte a rocking‐chair proton battery is built. The battery shows good cycling stability (85 % after 500 cycles), withstands rapid charging, with full capacity (60 mAh g−1) reached within 100 seconds, allows for direct integration with photovoltaics, and retains its favorable characteristics even at −24 °C., Combining naphthoquinone or hydroquinone redox‐active pendent groups, an all‐organic battery was designed to operate in aqueous electrolyte. This battery does not only show good capacity retention over 500 cycles but can also be charged ultra‐rapidly using a potential step, enabling easy integration with an organic solar cell.

Background Ophiopogonis radix and Liriopes radix are well known for the treatment of dry coughs and phthisis. Liriopes radix is occasionally used as a substitute for Ophiopogonis radix in various prescriptions due to the extremely similar pharmacological activities and clinical efficacies, but they are regarded as two different remedies in the Chinese Pharmacopoeia. Accordingly, the establishment of a reliable analytical approach for the discrimination and quality evaluation of Ophiopogonis and Liriopes is required. Objective To establish a simple, accurate, and reliable method that can simultaneously determine multiple components in Ophiopogonis radix and Liriopes radix. To comprehensively compare the chemical compositions of the two herbs and find markers for discrimination and quality assessments. Method An HPLC-ESI-triple quadrupole (QQQ)-MS/MS method was developed for simultaneous characterization and quantification of chemical components in the two herbs. The results were further analyzed by PLS discriminant analysis to provide more information about the chemical differences, as well as to evaluate the quality of each sample. Results A total of 23 compounds have been characterized and quantified in 31 batches of herbs from different geographical regions, among which liriopesides B, sprengerinin A, ophiopogonin B, and ophiopogonanone E contribute mostly. The contents of homoisoflavonoids were much higher in Ophiopogonis radix than in Liriopes radix, but the levels of steroidal saponins followed a contrary trend. Conclusions Simultaneous determination of multiple components by HPLC-QQQ-MS/MS coupled with chemometrics analysis is an acceptable strategy to evaluate and control the quality of Ophiopogonis radix and Liriope radix. Highlights Simultaneous determination of 12 steroidal saponins and 11 homoisoflavonoids in both Ophiopogonis radix and Liriope radix by using HPLC-QQQ-MS/MS in positive ion mode, as well as the quality control study.