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Liquid water in aerosol particles has a significant effect on their optical properties, especially on light scattering, whose dependence on chemical composition is investigated here using measurements made in southern Beijing in 2019. The effect is measured by the particle light scattering enhancement f(RH), where RH denotes the relative humidity, which is found to be positively and negatively impacted by the proportions of inorganic and organic matter, respectively. Black carbon is also negatively correlated. The positive impact is more robust when the inorganic matter mass fraction was smaller than 40 % (R=0.93, R: the Pearson's correlation coefficient), becoming weaker as the inorganic matter mass fraction gets larger (R=0.48). A similar pattern was also found for the negative impact of the organic matter mass fraction. Nitrate played a more significant role in aerosol hygroscopicity than sulfate in Beijing. However, the deliquescence point of ambient aerosols was at about RH = 80 % when the ratio of the sulfate mass concentration to the nitrate mass concentration of the aerosol was high (mostly higher than ∼ 4). Two schemes to parameterize f(RH) were developed to account for the deliquescent and non-deliquescent effects. Using only one f(RH) parameterization scheme to fit all f(RH) processes incurs large errors. A piecewise parameterization scheme is proposed, which can better describe deliquescence and reduces uncertainties in simulating aerosol hygroscopicity.

Daytime passive radiative cooling is a promising electricity-free pathway for cooling terrestrial buildings. Current research interest in this cooling strategy mainly lies in tailoring the optical spectra of materials for strong thermal emission and high solar reflection. However, environmental heat gain poses a crucial challenge to building cooling at subambient temperatures. Herein, we devise a scalable thermal insulating cooler (TIC) consisting of hierarchically hollow microfibers as the building envelope that simultaneously achieves passive daytime radiative cooling and thermal insulation to reduce environmental heat gain. The TIC demonstrates efficient solar reflection (94%) and long-wave infrared emission (94%), yielding a temperature drop of about 9 °C under sunlight of 900 W/m2. Notably, the thermal conductivity of the TIC is lower than that of air, thus preventing heat flow from external environments to indoor space in the summer, an additional benefit that does not sacrifice the radiative cooling performance. A building energy simulation shows that 48.5% of cooling energy could be saved if the TIC is widely deployed in China.

Ectomycorrhizal fungi (EMF) can enhance drought resistance of host plants by increasing nutrient and water absorption. Calcium (Ca) plays a central role in drought stress adaptation, yet it remains unclear how EMF influence Ca uptake of plants under drought stress. We carried out a pot experiment in which Quercus acutissima seedlings were inoculated with or without the ectomycorrhizal (EM) fungus Xerocomus chrysenteron under control and water stress soil moisture conditions in order to investigate how soil Ca availability and plant Ca uptake are modulated by EMF and how this may contribute to drought resistance of the seedlings. We found that soil water-extractable Ca was significantly reduced by drought in non-ectomycorrhizal treatment, while EM treatment significantly increased soil Ca availability and Ca uptake of Quercus acutissima seedlings under drought conditions. Furthermore, seedling water use efficiency (WUE) was positively correlated with soil Ca availability and plant Ca content. Calcium uptake promotion seems to be involved in the mechanisms of drought tolerance enhancement by EMF.

Developing cost-efficient electrocatalysts that are highly efficient and stable for pH-universal hydrogen evolution reaction (HER) is of great significance for scale-up electricity-to-fuel conversion. Herein, we report a free-standing cathode that the Pd NPs are embedded in a porous carbonized wood membrane (Pd@CWM) for efficient pH-universal HER. The 3D CWM not only serves as an effective porous matrix for hosting Pd nanoparticles with high dispersion but also acts as a conductive current collector. More importantly, the aligned open microchannels inside the CWM provide unimpeded pathways for electrolyte transport and gas release. Thanks to these structural benefits, the as-fabricated Pd@CWM electrodes display superior electrocatalytic activity for the HER, and the most efficient Pd@CWM-2 electrode only needs 154 and 302 mV overpotentials to deliver a HER current density of 10 mA cm−2 in 0.5 M H2SO4 and 1.0 M KOH, respectively. More impressively, Pd@CWM-2 electrode also exhibits excellent stability at a high current density (> 50 mA cm−2) for the HER with 100% faradaic efficiencies in both electrolyte solutions. This work provides a promising strategy for designing free-standing carbon membrane–based pH-universal electrode for large-scale clean fuel production.

Artemisinin (ART) is well known as an antimalarial drug, and it can also be used to treat inflammation as well as cancer. Although many researchers have reported the antitumor activity of ART, most of these studies were investigated in vitro. In addition, ART is sparingly soluble in water, limiting its clinical relevance in drug development. Based on the data from our preliminary study, ART is not cytotoxic at low micromolar concentrations. Thus, we hypothesized that smart nanocarriers are beneficial for not only increasing the solubility of ART but also elevating the concentration of the drug at the target, thereby inducing the ideal antitumor effect. In this article, a reversibly activatable cell-penetrating peptide ((HE)10-G5-R6 or HE-R6) was introduced to modify artemisinin (ART)-loaded liposomes (ART-Lip-HE-R6) against tumors, and in vitro and in vivo performance were investigated. ART-Lip-HE-R6 exhibited sustained release under different pH conditions. The internalization and cytotoxicity of liposomes were enhanced at low pH, i.e., 6.5, after modification with HE-R6 versus nonmodified liposomes. Moreover, a longer retention time in tumors could be observed in the ART-Lip-HE-R6 group, followed by higher efficiency of tumor suppression. In conclusion, Lip-HE-R6 might be a promising delivery system for ART in cancer therapy.

Lithium sulfur batteries with high energy density are thought to be the most potential energy storage technology that can be commercialized. However, the shuttle effect of polysulfides deteriorates its electrochemical performance. Herein, a novel Co9S8 nanostructure derived from metal organic framework material (MOF) was explored by simple liquid phase reaction and heat vulcanization of 2-methylimidazole and Co(NO3)2·6H2O on the surface of the original PP separator. The Co9S8 nano-flower cluster array wall was vertically and closely arranged with the thickness of 200 nm, and the polysulfide can be adsorbed by its physical and chemical action to slow down the “shuttle effect”. It is found that the cell with the modified separator can achieve an ideal discharge capacity of about 600 mAh/g at 1 C. The specific capacity is maintained at 500 mAh/g after 200 cycles, with only 0.11 % of capacity decay per cycle. It provides a new way for the utilization of MOF material derivatives to modify the separator in order to improve the electrochemical performance of lithium-sulfur batteries.

Exploring electrode materials with a high volumetric energy density and high rate capability remains of a great challenge for nanosized-Li4Ti5O12 (LTO) batteries. Here, hierarchical porous Ti3+-C-N-Br co-doped LTO (LTOCPB-CC) is synthesized using carboxyl-grafted nanocarbon (CC) and cetylpyridinium bromide (CPB) as combined structure-directing agents. Ti4+-O-CPB/Li+-CC is designed as a new molecular chelate, in which CPB and CC promote the uniform mixing of Li+ and Ti4+ and control the morphology of TiO2 and the final product. The defects (oxygen vacancies and ion dopants) formed during the annealing process increase the electron/hole concentration and reduce the band gap, both of which enhance the n-type electron modification of LTO. As-prepared LTOCPB-CC has a large specific surface area and high tap density, as well as a high electronic conductivity (2.84 × 10−4 S cm−1) and ionic conductivity (3.82 × 10−12 cm2 s−1), which are responsible for its excellent rate capability (157.7 mA h g−1 at 20 C) and stable long-term cycling performance (0.008% fade per cycle after 1000 cycles at 20 C).

Taking the VII oil group of N21 reservoir in Gasikule Oilfield as an example, the sedimentary time unit was divided into the barrier layer, interbed, and sand bed by analyzing the sedimentary system and sand body development model in this paper. The single sand body was analyzed for the sand bed time unit. The residual muddy intercalation period division theory was proposed for the first time to divide the sedimentary periods of the sedimentary time unit of the sand bed. Finally, a new “sandwich” layer point coincidence modeling technology was proposed to characterize the sedimentary time units of a barrier layer accurately and interbed and finely describe the sedimentary time unit of the multiperiod sand bed.

A comprehensive field experiment measuring aerosol chemical and physical properties at a suburban site in Beijing around the 2019 Spring Festival was carried out to investigate the impact of reduced anthropogenic emissions on aerosol formation. Sharply reduced sulfur dioxide (SO2) and nitrogen dioxide (NO2) concentrations during the festival holiday resulted in an unexpected increase in the surface ozone (O3) concentration caused by the strong O3-titration phenomenon. Simultaneously, the reduced anthropogenic emissions resulted in massive decreases in particle number concentration at all sizes and the mass concentrations of organics and black carbon. However, the mass concentrations of inorganics (especially sulfate) decreased weakly. Detailed analyses of the sulfur oxidation ratio and the nitrogen oxidation ratio suggest that sulfate formation during the holiday could be promoted by enhanced nocturnal aqueous-phase chemical reactions between SO2 and O3 under moderate relative humidity (RH) conditions (40 %

Background To investigate the pharmacokinetics of 6-O-demethylmenisporphine, an oxoisoaporphine alkaloid with significant anti-tumor activities and isolated from Menispermi Rhizoma, a novel and sensitive HPLC assay was established for 6-O-demethylmenisporphine quantification in rat plasma. Methods Peak responses were detected by a highly selective and sensitive fluorescence detector with 426-nm excitation and 514-nm emission wavelengths. Curcumin was employed as the internal standard (IS). A Capcell Pak C18 column (150 mm × 4.6 mm i.d., 5 μm) and an isocratic elution procedure with a flow rate of 1.0 mL/min were used to exclude the endogenous interfering substance. Acetonitrile-water (68:32, v/v) containing 1% formic acid was employed as mobile phase. A 7-point calibration curve that covered the concentration range of 10–2500 ng/mL was constructed. Results A good linearity was observed with a correlation coefficient (r) of 0.9993. The lower limit of quantification for 6-O-demethylmenisporphine was 10 ng/mL. The mean recoveries of analyte in rat plasma exceeded 80.5%. The precision at four concentration levels was within 11.3% and the accuracy ranged from − 7.6 to 6.7%. Conclusion Using this new HPLC-FLD method, the investigation of plasma samples from rats following oral dosing of neat compound and Menispermi Rhizoma extract was successfully conducted. The results will provide a reference for the evaluation of preclinical safety of 6-O-demethylmenisporphine.

A series of well-defined di- and triblock acrylic copolymers consisting of hard poly(dicyclopentanyl acrylate) (PdcPA) and soft poly(alkyl acrylate) (PAA) blocks are synthesized by the N-(trimethylsilyl)bis(trifluoromethanesulfonyl)imide (Me3SiNTf2) catalyzed group transfer polymerization (GTP) of dicyclopentanyl acrylate (dcPA) and alkyl acrylate (AA) including n-butyl acrylate (nBA), n-octylacrylate (nOA), 2-ethylhexyl acrylate (EHA), and n-dodecyl acrylate (nDA). The distribution of the monomeric units of the copolymers is controlled through the addition sequence of the comonomers and by the used initiator. In greater detail, the mixed addition of AA and dcPA using the monofunctional 1-methoxy-1-triisopropylsiloxy-2-methylpropene (MTSiPr) as the initiator produces the statistical poly[(alkyl acrylate)-stat-(dicyclopentanyl acrylate)] (Poly(AA-stat-dcPA)), the sequential addition of AA and then dcPA using MTSiPr as an initiator produces the AB-type hard–soft diblock poly(alkyl acrylate)-block-poly(dicyclopentanyl acrylate) (PAA-b-PdcPA), the sequential addition of AA and then dcPA using the bifunctional 1,2-bis[2-methyl-1-(triisopropylsiloxy)prop-1-enyloxy]ethane (MTSiPr2) as the initiator affords the ABA-type hard–soft–hard triblock poly(dicyclopentanyl acrylate)-block-poly(alkyl acrylate)-block-poly(dicyclopentanyl acrylate) (PdcPA-b-PAA-b-PdcPA), and the reverse addition of the two monomers using MTSiPr2 affords the soft–hard–soft BAB-type triblock poly(alkyl acrylate)-block-poly(dicyclopentanyl acrylate)-block-poly(alkyl acrylate) (PAA-b-PdcPA-b-PAA). The formation of the statistical and block copolymers has been confirmed by 1H NMR spectroscopy and size exclusion chromatography (SEC) measurements. Afterwards, the glass transition behavior of the resulting copolymers is analyzed by both differential scanning calorimetry (DSC) and rheometry. A detailed discussion of this part is presented in the following sections.

Metal halide perovskites are emerging semiconducting materials with a wide range of applications, including photovoltaics, thin-film transistors, and light-emitting diodes. A key advantage of perovskites over more established semiconductor technologies is solution processability, which reduces processing costs and enables rapid production by roll-to-roll printing. However, metal halide perovskites suffer from poor thermomechanical and chemical stability that must be overcome for successful commercialization of perovskite-based technologies. These instabilities have been shown to stem from defect states present at perovskite interfaces, and particularly grain boundaries, that result in destructive trap states. This review focuses on one successful strategy—organic additive engineering—that has been demonstrated to inhibit the formation of defect sites in perovskite films. This review begins by discussing defects present at grain boundaries—e.g., undercoordinated bonds, vacancies, and antisites—that develop during crystallization, and how these defects lead to reduced device performance via non-radiative recombination and hysteresis, as well as poor chemical and thermal stability. The bulk of this review is dedicated to additive engineering strategies to enhance performance and stability in 3D, quasi-2D, and 2D perovskites. Lewis acid–base interactions between the additives and perovskite constituents are highlighted, with additives ranging from small molecules and solvents to polymers. Special attention is paid to Lewis base additives containing amino and/or carbonyl functional groups, and a short discussion on semiconducting additives for improved charge transport is also included. This review concludes by identifying several areas of further discovery in organic additives for metal halide perovskites.

Most cluster identification studies regarding consumer electricity load is faced with problems of erroneous clustering method similarity, low clustering quality and poor identification accuracy. To solve these problems, this paper utilizes the elbow method, k- Means ++, entropy weight method and a graph convolutional neural network to provide a means for cluster identification based on electrical appliance power data collected via smart sockets. In this article, elbow and entropy weight methods were used to achieve the adaptive clustering algorithm. To obtain the electrical appliance load curves, Euclidean and dynamic time warping (DTW) distances were integrated and the similarity measurement method was used to improve the k-means ++ algorithm, which was then applied to data collected via smart socket clustering. Next, clustering results were input into the graph convolutional neural network (GCN) for identification purposes and appliance type information was obtained. Finally, experiments were conducted using electrical load data from 20 commercial users. The method used was a combination of the k-means algorithm and long short-term memory network (LSTM). The results show that under optimal K value conditions (as determined by the elbow score), the methods used in this paper have improved clustering quality and recognition accuracy, when compared to LSTM.

In this paper, the finite-time position tracking control for the fractional-order permanent magnet synchronous motor with input saturation, load disturbance and parameter uncertainties is considered. Based on the command filtered backstepping method, a novel adaptive neural network finite-time controller is presented. First, the neural network is introduced to approximate the uncertain function. Then, by using a command filter at the output side of the virtual signal, the issue of “explosion of complexity” is avoided. In addition, an adaptive law is applied to eliminate the approximation error and filtering error. Meanwhile, by utilizing the terminal sliding mode control technique, the finite-time signal tracking is achieved. Furthermore, an auxiliary design system is constructed to cope with the input saturation constraint. The proposed scheme not only possesses the superiorities of the classical command filtered backstepping, but also holds quick finite-time convergence property. Numerical simulations and experiment results are included to reveal the validity of the proposed design.

The tumor microenvironment (TME) significantly influences cancer evolution and therapeutic efficacy. Targeting biofunctional molecules to the TME has long been appreciated as a means of raising local drug concentrations and reducing systemic toxicities. The booming nanotechnology field has realized the importance of cathepsin B to derive a variety of intelligent enzyme-responsive nanosized drug delivery systems (nanoDDS) to improve treatment responses and clinical outcomes. In this tutorial review, after introducing the molecular structure and physiological/pathological functions of cathepsin B, the outstanding achievements of cathepsin B-responsive nanoplatforms in the precise diagnosis, targeted therapy, and synergistic theranostics of malignant tumors are systematically described. Finally, the challenges of enzyme-substrate incompatibility, low diagnostic sensitivity, mass production and biocompatibility of multifunctional nanoDDS are considered in order to successfully promote them to clinical applications

In this work, a CoNxC active sites-rich three-dimensional porous carbon nanofibers network derived from bacterial cellulose and bimetal-ZIFs is prepared via a nucleation growth strategy and a pyrolysis process. The material displays excellent electrocatalytic activity for the oxygen reduction reaction, reaching a high limiting diffusion current density of −7.8 mA cm−2, outperforming metal–organic frameworks derived multifunctional electrocatalysts, and oxygen evolution reaction and hydrogen evolution reaction with low overpotentials of 380 and 107 mV, respectively. When the electrochemical properties are further evaluated, the electrocatalyst as an air cathode for Zn-air batteries exhibits a high cycling stability for 63 h as well as a maximum power density of 308 mW cm−2, which is better than those for most Zn-air batteries reported to date. In addition, a power density of 152 mW cm−2 is provided by the solid-state Zn-air batteries, and the cycling stability is outstanding for 24 h. The remarkable electrocatalytic properties are attributed to the synergistic effect of the 3D porous carbon nanofibers network and abundant inserted CoNxC active sites, which enable the fast transmission of ions and mass and simultaneously provide a large contact area for the electrode/electrolyte.

Daytime radiative cooling is a passive strategy to cool down a terrestrial object under direct sunlight without the need of electricity input. It functions by simultaneously reflecting solar irradiance and sending heat as infrared (IR) thermal radiation through the atmospheric transparent window into the cold outer space. In spite of extensive studies on daytime radiative cooling, most of previous works were conducted in dry regions mainly in North America. Here, we explore the feasibility of achieving efficient radiative cooling in humid subtropical areas such as Hong Kong, where abundant atmosphere water vapor exists. In this case, the atmospheric transparent window is almost closed since water is highly absorptive of IR radiation. We report a simple approach to achieve efficient daytime radiative cooling in Hong Kong. Our design comprises an expanded polytetrafluoroethylene (ePTFE) film and a Ag layer deposited on a transparent glass substrate. We show that the combination of highly diffusely reflective ePTFE and all-band reflective Ag results in a reflectivity of 98% in the solar spectrum, allowing for a temperature drop up to 2.7 °C under a solar intensity of 1000 W/m2 on a humid day in Hong Kong.

Garcinia mangostana L. (mangosteen) is a famous tropical fruit that contains a large number of xanthones. Regular consumption of mangosteen may confer health benefits and prevent some diseases, such as malaria. Quinone reductase 2 (QR-2) is a cytosolic enzyme found in human red blood cells, and it is becoming a target for chemoprevention because it is involved in the mechanisms of several diseases, including malaria. To understand whether the xanthones present in mangosteen might inhibit the activity of QR-2, blood samples were collected from rat following the oral administration of mangosteen extract and then incubated with QR-2 followed by UF-HPLC-QTOF/MS analysis to rapidly screen for and identify the QR-2-inhibiting xanthones. A total of 16 xanthones were identified, and six of these (α-mangostin, γ-mangostin, 8-deoxyartanin, 1,3,7-trihydroxy-2,8-di(3-methylbut-2-enyl)xanthone, garcinone E, and 9-hydroxycalabaxanthone) were subjected to QR-2 inhibition assay. γ-Mangostin exhibited the strongest inhibition, achieving an IC50 value of 3.82 ± 0.51 μM. Its interaction with QR-2 was found to involve hydrogen bond and arene-arene interaction as revealed by molecular docking. The present study could provide new insight into the potential application of mangosteen as functional food ingredients for inhibiting the activity of QR-2. However, the extent of daily intake of mangosteen required and the exact contribution of mangosteen to the prevention and treatment of malaria remain subjects of further study.

Multiple pollutants including pathogenic microorganism contaminations and emerging organic contaminations (EOCs) have shown a growing threat to the environment, especially the natural waters. However, the control and removal of pathogenic microorganism contaminations and EOCs have been greatly limited since limited knowledge of their environmental behaviors. Thus, a novel and efficient photocatalyst Ag2O/BiOBr heterojunction was synthesized and used for removal of multiple pollutants including Escherichia coli (E. coli), Staphylococcus aureus (S. aureus), tetracycline and acetaminophen under visible light. The results showed that there were valid electron transfer pathways between BiOBr and Ag2O, the main electron transfer direction was the BiOBr to Ag2O. Photo-generated electrons were stored in Ag2O and thus separation efficiency between holes and photo-generated electrons was obviously enhanced. Active oxygen species were highly produced and eventually end up with the high efficiency of removal of multiple pollutants. For Ag2O/BiOBr with Ag2O content at 3% (the best performance) under visible light, log decrease of E. coli was 7.16 (removal efficiency was 100%) in 120 min, log decrease of S. aureus was 7.23 (removal efficiency was 100%) in 160 min, C/C0 of tetracycline was 0.06 in 180 min, C/C0 of acetaminophen was 0.17 in 180 min. This work could provide a promising candidate in the actual contaminated natural waters for cleaning multiple pollutants.

Development of composite adsorbents having high removal efficiency as well as convenient separation and regeneration properties is important for water treatment. This study synthesized magnetic activated carbon (MAC) from activated carbon (AC) by impregnation of iron oxides in the porous structure. Systematic characterization results demonstrated that MAC contained Fe3O4 and had size of ∼0.5 mm, saturated magnetization of 8.99 emu/g, specific surface area of 473 m2/g, and pore volume of 0.54 cm3/g. Batch adsorption experiments were conducted using 4-chlorophenol (4-CP) as the probing pollutant and both MAC and AC as the adsorbents. Results showed that the adsorption rate followed intra-particle diffusion model and pseudo-second-order rate model, and that the adsorption equilibrium can fit to Freundlich isotherm equation. After adsorption, H2O2 was added to initiate a heterogeneous Fenton reaction catalyzed by impregnated Fe3O4 on MAC. More than 90% of aqueous 4-CP was degraded within 1 h, with optimal conditions of pH 3.0, 20 mM H2O2, and Fe2+/Fe3+ ratio of 3:1. After 5 cycles of adsorption-regeneration, the MAC composite remained >80% removal efficiency for 4-CP, indicating that it could be reused as an effective and retrievable adsorbent in water treatment of organic pollutants.

Raritan River is the largest river basin in New Jersey, providing the water supply for one million people in seven counties nearby. In this study, water samples collected from 11 Raritan River standard sampling stations along the Raritan Estuary to the Atlantic Ocean were analyzed for concentrations of trace metals and their isotopes. The concentration of each trace metal was measured with inductively coupled plasma mass spectrometer (ICP-MS), with normalization of internal standard and correction with acid blanks. The metal concentration levels were compared to the National Recommended Water Quality Criteria (NRWQC). Results showed that the metal concentrations generally increased with the sampling station number, indicating that more trace metals were distributed in seawater than freshwater along the river basin. None of the sampling stations had concentrations of 52Cr or 208Pb exceeding the NRWQC. For 64+66Zn, only the water concentration (230 μg/L) at station 7 has exceeded the NRWQC. The concentrations of 75As at stations 9, 10, and 11 have exceeded the NRWQC, possessing potential risk for causing chronic disease. Furthermore, 63+65Cu and 106+111Cd concentrations at all sampling stations exceeded the limit set by NRWQC. Considering the potential health hazards of these trace metals, the sampling sites with excessive concentrations should be monitored.

Introduction Oxaliplatin (L-OHP) is a well-known third-generation platinum anticancer drug with severe systemic- and neuro-toxicity. The main objective of the current research was to develop a targeted long-circulating thermosensitive smart-release liposome (LCTL) system for better therapeutic efficacy and less toxicity. Methods The reverse-phase evaporation method (REV) was used to prepare L-OHP loaded LCTL (L-OHP/LCTL). The physical characteristics were evaluated including encapsulation efficiency (EE), size, zeta potential and stability. The release behavior, cytotoxicity and in vivo evaluation were also carried out. Results EE of LCTL was around 25% with a uniform size distribution, and LCTL achieved almost complete release at 42°C while it was only 10% at 37°C. Moreover, the LCTL showed significantly higher cytotoxicity at 42°C than that at 37°C. The in vivo results indicated LCTL could target tumors and enhance retention for more than 24 h, thereby enhancing anti-tumor efficacy on 4T1-bearing mice. Discussion These results indicated that LCTL not only possessed a prolonged circulation time but it also enhanced accumulation and achieved selective release at the tumor sites. Conclusively, LCTL could serve as a promising carrier for oxaliplatin delivery to treat solid tumors.

This study investigated the distribution of 209 polychlorinated biphenyl (PCB) congeners in sediment samples collected from seven sites in the Raritan River estuary (NJ, USA) using gas chromatography/tandem quadrupole mass spectrometry (GC/MS/MS). Results showed that concentrations of 209 PCB congeners ranged up to 20 ng/g, that total PCB concentrations by homolog groups varied from 9.0 to 327 ng/g, and that total PCB mass ranged from 101.0 to 1,476.3 ng with the order of sites 6 > 7 > 3 > 4 > 2 > 1 > 5. Furthermore, higher PCB concentrations were detected for homolog groups including hexa- and hepta-PCBs. More PCBs were associated with sediments at downstream sites possibly due to accumulation and deposition in the estuary, as supported by strong correlations of PCB concentrations between different sampling sites (R2 ≤ 0.96). Comparisons with prior reports showed that all total PCB concentrations were below those reported by the Contamination Assessment and Reduction Project (CARP) and Delaware River Basin Commission (DRBC), except for sites 6 and 7. Sites 3 and 4 had PCB concentrations exceeding the 22.7 ng/g limit of the Sediment Quality Guidelines (SQGs), whereas sites 6 and 7 exceeded the 180 ng/g limit, indicating potential health hazards from PCBs.

The paper investigates the well-posedness and longtime dynamics of the Kirchhoff wave model with structural nonlinear damping: u t t − ϕ ( ‖ ∇ u ‖ 2 ) Δ u + σ ( ‖ ∇ u ‖ 2 ) ( − Δ ) θ u t + f ( u ) = g ( x ) , with θ ∈ [ 1 / 2 , 1 ) . We find a new critical exponent p ⁎ ≡ N + 2 N − 2 ( > p θ ≡ N + 2 θ N − 2 , N ≥ 3 ) and show that when the growth exponent p of the nonlinearity f ( u ) is up to the range: 1 ≤ p p ⁎ : (i) the IBVP of the equation is well-posed and its solution is of additionally global regularity when t > 0 ; (ii) for each θ ∈ [ 1 / 2 , 1 ) , the related solution semigroup has in natural energy space H an optimal global attractor A θ whose compactness and attractiveness are in the regularized space H 1 + θ where A θ lies, and an optimal exponential attractor E θ ⁎ whose compactness, boundedness of the fractional dimension and the exponential attractiveness are in H 1 + θ where E θ ⁎ lies, respectively; (iii) the family of global attractors { A θ } θ ∈ [ 1 / 2 , 1 ) is upper semi-continuous at each point θ 0 ∈ [ 1 / 2 , 1 ) . The paper breaks though the longstanding existed growth restriction: 1 ≤ p ≤ p θ for p θ had been considered a uniqueness index, deepens and extends the results in literature [6] , [25] , [27] .

We develop a rapid and ulsensitive colorimetric method for alkaline phosphatase (ALP) activity based on dark-field microscope. In the presence of ALP, the ALP will hydrolyze L-ascorbic acid 2-phosp...

This study proposes a method for a vehicle controller to learn human driving behaviours through iterative interactions. In particular, the vehicle controller and the human driver jointly control a vehicle along a path only known to the human driver. Through repeated cooperative driving, the vehicle controller estimates the hidden desired path of the driver by minimising the control input. Eventually, semi-autonomous driving is realised since the vehicle controller is able to automatically track the target path and release the human driver from the driving task. The iterative learning of the human target path on the basis of the proposed algorithm is in the spatial domain, and is effective in the presence of uncertain human driving speeds. The validity of the proposed method is proved by rigorous analysis and demonstrated by numerical simulations.

A novel quaternary selenide (Na0.60Ba0.70)Ga2Se4 (1) obtained by a high-temperature method crystallizes in the non-centrosymmetric space group I4cm, and its structure features {[GaSe2]−}∞ chains. I...

A dual-function fluorescent probe (Probe 1) was developed for discriminative detection of Hg2+ and N2 H4 . Probe 1 could discriminatively detect Hg2+ and N2 H4 through two different reaction sites, with the mechanism for Probe 1 for Hg2+ depending on a desulfurization reaction and for N2 H4 depending on the Schiff-base reaction. N2 H4 had minimal effect on Hg2+ detection in dimethyl sulfoxide (DMSO)/H2 O solution, but Hg2+ could interfere with N2 H4 detection in DMSO/buffer solution. Different concentrations of Hg2+ and N2 H4 resulted in different blue shades of Probe 1 test strips, and the shade of blue was different with the same concentration of Hg2+ or N2 H4 , as observed under ultraviolet light at 365 nm wavelength.

New antimicrobial agents are urgently needed to address the emergence of multi-drug resistant organisms, especially those active compounds with new mechanisms of action. Based on the molecular structures of the FtsZ inhibitors reported, a variety of thiazole-quinolinium derivatives with aliphatic amino and/or styrene substituents were synthesized from benzothiazolidine derivatives. In the present study, to further explore the antibacterial potential of thiazole-quinolinium derivatives, several Gram-positive and Gram-negative bacteria were treated with the newly modified compounds and the biological effects were studied in detail in order to understand the bactericidal action of the compounds. Our findings reveal that some of these derivatives possess good potent bactericidal activity as they can inhibit Gram-positive methicillin-resistant Staphylococcus aureus, vancomycin-resistant Enterococcus and also some Gram-negative organisms and NDM-1 Escherichia coli. Furthermore, compounds 4a1–4a4 and 4b1–4b4 altered the morphology of bacterial cells and the cells displayed a more-elongated shape compared to the untreated cells. Biochemical assays showed that 4a4 and 4b4 stimulate FtsZ polymerization in bacterial cells, which eventually disrupts its dynamic assembly and Z-ring formation. The inhibition of this crucial step in bacterial cell division could potentially represent their main mechanism of antibacterial activity. Cytotoxicity assay and hemolysis assay suggested that 4a4 and 4b4 possess low cytotoxicity. In summary, these results further highlight the importance of 4a4 and 4b4 that could be developed as potent and effective bacteriostatic agents against multi-drug resistant bacteria.

The paper studies the existence of the pullback attractors and robust pullback exponential attractors for a Kirchhoff-Boussinesq type equation: \begin{document}$ u_{tt}-\Delta u_{t}+\Delta^{2} u = div\Big\{\frac{\nabla u}{\sqrt{1+|\nabla u|^{2}}}\Big\}+\Delta g(u)+f(x,t) $\end{document} . We show that when the growth exponent \begin{document}$ p $\end{document} of the nonlinearity \begin{document}$ g(u) $\end{document} is up to the critical range: \begin{document}$ 1\leq p\leq p^*\equiv\frac{N+2}{(N-2)^{+}} $\end{document} , (ⅰ) the IBVP of the equation is well-posed, and its solution has additionally global regularity when \begin{document}$ t>\tau $\end{document} ; (ⅱ) the related dynamical process \begin{document}$ \{U_f(t,\tau)\} $\end{document} has a pullback attractor; (ⅲ) in particular, when \begin{document}$ 1\leq p , the process \begin{document}$ \{U_f(t,\tau)\} $\end{document} has a family of pullback exponential attractors, which is stable with respect to the perturbation \begin{document}$ f\in \Sigma $\end{document} (the sign space).

This paper presents a thorough evaluation of twenty-one state-of-the-art widely-used crop segmentation algorithms, motived by their significance in vision tasks for further analysis. An ideal crop segmentation algorithm can effectively extract crop information, thus providing an important precondition for the application of intelligent agriculture analytics. In order to enable researchers in this field to fully understand various crop segmentation methods, this paper proposes a new classification strategy of object segmentation by dividing the algorithms into pixel-based and region-based approaches at first, and then systematically evaluating various crop segmentation methods with a unified data benchmark and four common metrics. A new dataset which incorporates crop variety, environment condition and observation distance into consideration is constructed for demonstrating the experiments and comparisons. The effectiveness and robustness of these algorithms were evaluated by three sets of comparative experiments. Based on the quantitative results, we summarize the advantages and disadvantages of the evaluated algorithms from the segmentation performances with four metric indicators. Furthermore, the discussion and evaluation results will provide great support for precision agriculture analysis.

The paper investigates the robustness of pullback attractors and pullback exponential attractors of the non-autonomous Kirchhoff wave models with strong nonlinear damping: $$u_{tt}- (1+\epsilon \Vert \nabla u\Vert ^2)\Delta u-\sigma (\Vert \nabla u\Vert ^2) \Delta u_t+f(u)=g(x,t)$$ , where $$\epsilon \in [0,1]$$ is an extensibility parameter. It shows that when the growth exponent p of the nonlinearity f(u) is up to the supercritical range: $$1\le p

High-throughput drug discovery is highly dependent on the targets available to accelerate the process of candidates screening. Traditional chemical proteomics approaches for the screening of drug targets usually require the immobilization/modification of the drug molecules to pull down the interacting proteins. Recently, energetics-based proteomics methods provide an alternative way to study drug-protein interaction by using complex cell lysate directly without any modification of the drugs. In this study, we developed a novel energetics-based proteomics strategy, the solvent-induced protein precipitation (SIP) approach, to profile the interaction of drugs with their target proteins by using quantitative proteomics. The method is easy to use for any laboratory with the common chemical reagents of acetone, ethanol, and acetic acid. The SIP approach was able to identify the well-known protein targets of methotrexate, SNS-032, and a pan-kinase inhibitor of staurosporine in cell lysate. We further applied this approach to discover the off-targets of geldanamycin. Three known protein targets of the HSP90 family were successfully identified, and several potential off-targets including NADH dehydrogenase subunits NDUFV1 and NDUFAB1 were identified for the first time, and the NDUFV1 was validated by using Western blotting. In addition, this approach was capable of evaluating the affinity of the drug-target interaction. The data collectively proved that our approach provides a powerful platform for drug target discovery.

Poly (N-isopropylacrylamide) (PNIPAM) is an intelligent hydrogel which exhibits volume transition in response to temperature change. This work reports the PNIPAM/AM-QDs hybrid hydrogels, in which N-isopropylacrylamide, acrylamide as monomers and CdTe/CdS quantum dots (QDs) as filler, are prepared by glow discharge electrolysis plasma (GDEP). The hydrogels are investigated by transmission electron microscopy (TEM), X-ray diffraction (XRD), FTIR spectra, differential scanning calorimetry (DSC) and PL spectra, as well as the swelling rate, temperature sensitivity and fluorescence reversibility. The results show that the PNIPAM hydrogels and QDs are cross-linked by coordination bond, and the QDs are well dispersed and combined firmly in the networks of the hydrogels. The phase transition temperature of PNIPAM/AM-QDs hybrid hydrogels is 32.5°C. The fluorescence intensity of hydrogels is 1490 a.u. and 20 a.u. at 20 and 40°C, respectively. Furthermore, the luminescence intensity of hydrogels is almost not weakened after five heating-cooling cycles, which should be used as a temperature-controlled light switch.

In this work, we design a three-dimensional (3D) strongly-coupled polyaniline/crosslinked carbon nanosheets (PANI/CCNs) composite using a facile in-situ chemical polymerization method. The PANI is uniformly and conformally covered on the thin graphene-like biomass-derived CCNs. The interconnected CCNs with high surface area and electrical conductivity can expose more active sites of PANI and enhance the interfacial electron transfer, which contributes to the improvement of specific capacitance and rate performance. The sheets-like PANI can introduce pseudocapacitance through the surface redox reactions on the surface. As a result, the PANI/CCNs composite electrode can reach high specific capacitance of 444 and 340 F g−1 at current densities of 0.1 and 5 A g−1, respectively. The assembled PANI/CCNs//PANI/CCNs symmetric supercapacitor can reach a high specific capacitance of 72.0 F g−1 at a current density of 0.1 A g−1. Moreover, the PANI/CCNs//PANI/CCNs symmetric cell exhibits a high energy density of 28.9 Wh kg−1 at a power density of 85.1 W kg−1, which is competitive in the aqueous PANI-based symmetric supercapacitors.

With the phasing out of traditional polybrominated diphenyl ethers (PBDEs), significant volumes of alternative brominated flame retardants (aBFRs) are being used and released into the environment compartment, especially in coastal regions. The levels and distribution of PBDEs, aBFRs, and dechlorane plus (DPs) were investigated in the surface sediments of the Yellow Sea (YS) and East China Sea (ECS) to examine the distribution and sources of these hydrophobic contaminants. The level and distribution of pollutants in the sediments of YS and ECS show obvious regional differences. As a major replacement for decabromodiphenyl ether (BDE 209), decabromodiphenyl ethane (DBDPE) was the dominant compound observed in the surface sediments, with a concentration one order of magnitude higher than that of BDE 209. High concentrations were found in the depositional zones of the YS, indicating that these contaminants may originate from land-based pollution sources (likely from the Laizhou Bay manufacturing base) near the Bohai Sea. The pollutants can be carried by the coastal current together with the sediment from the Yellow River, transported through the Bohai Strait and deposited in the mud zone of Northern and Southern YS. Low levels of halogenated flame retardants (HFRs) were found in the estuary of the Yangtze River and ECS, indicating that Yangtze River contributes less HFRs to the region. Riverine discharge, atmospheric deposition, surface runoff, ocean current system, and mud area deposition effects may be significant factors influencing the distributions of HFRs.

Phenolic compounds are the dominant pollutants in soils contaminated by the coking industry. Ring opening by the hydroxylase gene (bamA) is the key step in the benzoyl-CoA degradation pathway under anaerobic conditions, and a broad spectrum of microorganisms possesses this functional gene, including denitrifiers. The present study analyzed the community structure of denitrifying bacteria and the diversity of the bamA gene for mixed cultures enriched from soil collected at a coking industrial site and then grown under nitrate-reducing conditions on phenol or p-hydroxybenzoate (4HBA), a key intermediate product of anaerobic phenol degradation. Illumina sequencing of the 16S rRNA gene showed different bacterial compositions between the two cultures. The dominant phyla were Proteobacteria, Armatimonadetes, and Planctomycetes in the phenol culture and Proteobacteria and Bacteroidetes in the 4HBA culture. Phylogenetic analysis further demonstrated that bamA genes were associated with four clusters of bacteria, three of known bacteria and one of uncultured bacteria. The diversity of the bamA gene differed from that reported in anaerobic aromatic degradation cultures, suggesting that these enriched cultures may contain new strains unique to coking-contaminated soils. The present study further validates the potential application of this functional gene as a marker for anaerobic biodegradation processes in enrichment cultures from contaminated soil.

This study aims to investigate how multiple parameters affect the two-phase flow in compressed gas diffusion layer (GDL). A stochastic model is adopted to reconstruct the GDL microstructures. Solid mechanics simulations on the reconstructed GDL microstructures are performed, based on the finite element method (FEM). Various pore morphologies and distributions of compressed GDLs are observed. Two-phase flow in GDL is simulated using a volume of fluid (VOF) model. Corner droplet (on the GDL surface) and water flow (emerging from GDL bottom) are considered. It is found that two-phase flow in the GDL is highly influenced by compression, fiber diameter, porosity, and GDL thickness. The results indicate that a larger fiber diameter or higher porosity contributes to the water transport due to larger average pore size. Furthermore, water removal from a thicker GDL is more difficult, whereas water transport in the lower part of a compressed thick GDL is easy.

COVID-19 is threatening the whole world. This paper aims to explore the correlation between climatic factors and the morbidity of COVID-19 in Wuhan, China, mainly by using a geographic detector and GWR model. It was found that the response of the morbidity of COVID-19 to meteorological factors in Wuhan is different at different stages. On the whole, the morbidity of COVID-19 has a strong spatial aggregation, mainly concentrated in the central area of Wuhan City. There is a positive correlation between wind speed and the spread of COVID-19, while temperature has a negative correlation. There is a positive correlation between air pressure and the number of COVID-19 cases. Rainfall is not significantly correlated with the spread of COVID-19. It is concluded that wind speed, relative humidity, temperature, and air pressure are important meteorological factors affecting the spread of COVID-19 in Wuhan. Any two variables have greater interaction with the spatial distribution of the incidence rate of COVID-19 than any one factor alone. Those findings not only provide a new insight for the key intervention measures and the optimal allocation of health care resources accordingly but also lay a theoretical foundation for disease prevention, disease intervention and health services.

Research on the anomalous Hall effect (AHE) has been lasting for a century to make clear the underlying physical mechanism. Generally, the AHE appears in magnetic materials, in which the extrinsic process related to scattering effects and intrinsic contribution connected with Berry curvature are crucial. Recently, AHE has been counterintuitively observed in nonmagnetic topological materials and attributed to the existence of Weyl points. However, the Weyl point scenario would lead to unsaturated AHE even in large magnetic fields and contradicts the saturation of AHE in several tesla (T) in experiments. In this work, we investigate the Hall effect of $\mathrm{Zr}{\mathrm{Te}}_{5}$ and $\mathrm{Hf}{\mathrm{Te}}_{5}$ thin flakes in static ultrahigh magnetic fields up to 33 T. We find the AHE saturates to $55\phantom{\rule{0.16em}{0ex}}(70)\phantom{\rule{0.16em}{0ex}}{\mathrm{\ensuremath{\Omega}}}^{\text{}1}\phantom{\rule{0.16em}{0ex}}\mathrm{c}{\mathrm{m}}^{\text{}1}$ for $\mathrm{Zr}{\mathrm{Te}}_{5}$ ($\mathrm{Hf}{\mathrm{Te}}_{5}$) thin flakes above $\ensuremath{\sim}10\phantom{\rule{0.16em}{0ex}}\mathrm{T}$. Combining detailed magnetotransport experiments and Berry curvature calculations, we clarify that the splitting of massive Dirac bands without Weyl points can be responsible for AHE in nonmagnetic topological materials $\mathrm{Zr}{\mathrm{Te}}_{5}$ and $\mathrm{Hf}{\mathrm{Te}}_{5}$ thin flakes. This model can identify our thin flake samples to be weak topological insulators and serve as a tool to probe the band structure topology in topological materials.

Malus toringoides belongs to the subfamily Amygdaloideae of Rosaceae, which is an endemic species in China. It has significant ornamental, economic, and ecological value. Herein, we assembled the complete chloroplast genome of Malus toringoides using the next-generation sequencing technology. The total length of the complete chloroplast genome was 160,093 base pair (bp), consisting of one large single-copy (LSC) region with a sequence length of 88,177 bp, one small single-copy (SSC) region which sequence length is 19,194 bp, and a pair of inverted repeat regions (IRs, 26361 bp). Besides, the complete chloroplast genome contained 128 genes, namely 83 protein-coding genes (PCGs), 37 tRNA genes (tRNA), and 8 rRNAgenes (rRNA), the GC content was 36.6%. The phylogenetic relationship among species in genus Malus is closely related, especially the phylogenetic relationship among Malus angustifolia, Malus prattii, Malus micromalus, Malus prunifolia, Malus baccata, Malus hupehensis and Malus toringoides. Furthermore, phylogenetic relationship of Malus toringoides in Malus was closely related to Malus hupehensis. Our study affords important genetic information for further researches on the related species.

Catechins are major antioxidant constituents of green tea, which have attracted much attention as human health promoters. To identify catechins, we built a chrono-colorimetric sensor array for iden...

Black carbon (BC) is one of the most important climate pollutants due to its strong positive radiative forcing on the climate system. However, long-term observation of BC is inadequate, and its trend remains unknown at both regional and global scales. In this study, using quality-controlled ground-based black carbon observations at 34 stations, the climatology of BC mass concentration during 2006–2017 in China was evaluated for the first time. The national annual average BC concentration was 3534 ng/m^3, and the concentration exhibited large spatial variation, from a minimum of 272 ng/m^3 to a maximum of 10,228 ng/m^3. Significant seasonal variations were also observed. The peak BC concentration (4763 ± 3380 ng/m^3) occurred during winter, followed by autumn (3752 ± 2623 ng/m^3) and spring (3022 ± 2121 ng/m^3). The lowest BC concentration occurred in summer (2583 ± 1780 ng/m^3) due to decreased emissions, wet removal by precipitation, and diffusion induced by strong turbulent mixing. Additionally, the diurnal variability at about 80% of the stations in China showed a bimodal pattern. Daily maximum BC concentration during 0000–0600, 0600–1200, 1200–1800, and 1800–2400 local solar time accounted for 0, 41, 12, and 47% of the total, respectively. In particular, the diurnal and monthly variations in BC were explicitly analyzed at seven baseline stations. Surface BC has exhibited a significant declining trend across China, which is partly corroborated by the increase in single scattering albedo during the same period in Beijing. Also, the BC radiative forcing at the top of the atmosphere has declined at the rate of − 0.9 ± 0.1 W/m^2/10 years over China, which differs from with the trend in the simulation using the CMIP6 emission. The decreasing BC has led to a larger reduction rate in atmospheric heating (− 3.7 ± 0.4 W/m^2/10 years), implying a less stable atmosphere that facilitates the dispersion of air pollutants. The declining BC burden implies for both the air quality in China and regional climate change.

Changes in soil carbon (C) and nitrogen (N) stocks following afforestation have been widely studied at different scales. However, soil phosphorus (P) dynamics following afforestation are poorly understood, especially at the regional scale. This paper studied the effects of prior land use (cropland, grassland, and barren land), tree species (conifer, broadleaf, shrub, and mixed), plantation age (young, middle, and old), and climate on soil total phosphorus and available phosphorus stocks change in the top 20 cm following afforestation based on a synthesis of 50 recent publications in northern China. We also considered possible confounding effects between these factors. The results showed that, overall, soil total phosphorus and available phosphorus stocks significantly decreased by 7.3% and significantly increased by 8.8%, respectively, following afforestation. Prior land use was found to be the most important driver in determining changes in soil P stocks. Compared with a significant decrease in P of afforestation of former cropland and grassland, afforestation of barren land caused no clear decrease in P. Tree species was found to have a limited effect on changes in soil P after afforestation, and broadleaf afforestation has a lower P demand than coniferous forests in the studied region. Plantation age did not affect the dynamics of P stocks. Our results showed confounding effects of precipitation, prior land use, and tree species, which impacted the estimates of the drivers of changes in P stocks. These results highlighted the importance of tree species selection and replication across sites that receive different amounts of precipitation.

Nanosized Li4Ti5O12 with both a Li2TiO3 coating and C-N-Br co-doping (CLLTO) was successfully synthesized via a facile reverse microemulsion method in one step using hexadecyl trimethyl ammonium bromide as a surface control agent and as a carbon, nitrogen, and bromine source. A uniform Li2TiO3 layer was formed on the surface and strongly adhered to the host material Li4Ti5O12 (LTO), which played an important role in improving the cyclic stability of CLLTO. The thin and stable Li2TiO3 layer has the same cubic structure as LTO, which provides many three-dimensional channels for ion transport. C, N, and Br co-doping in CLLTO promoted the transition of Ti4+ to Ti3+ in Li4Ti5O12, which could improve the capacity and facilitate the Li+ ion and electron transfer at the interface. The conductive behavior induced by co-doping was estimated by UV-vis diffuse reflectance spectra and further supported by theoretical calculations. The electrical conductivity of both p-type and n-type LTO can be well improved by co-doping C, N, and Br. This improvement may be due to the band gap reduction and the increased n-type electronic modification of the entire LTO. Owing to the synergistic effect of coating, co-doping, and nanosizing at one time, the CLLTO exhibits a high discharge capacity of 177.3-153.9 mA h g-1 at the working rate of 0.1C-20C, with a capacity retention of 86%. The stable cycling of CLLTO is also obtained after 500 cycles at 20C, with a capacity retention of 95.5% (approximately 8 times higher than that of pure LTO) and almost 100% Coulombic efficiency. With high capacity, excellent rate performance, and good cycling stability, CLLTO can be applied in high-power lithium-ion batteries.

Two energetic compounds, 1-amino-1-picrylamino-2,2-dinitroethylene (APDE) and its potassium salt [K(APDE)] were synthesized through an aromatic nucleophilic substitution reaction between FOX-7 and picryl chloride. APDE and K(APDE) were characterized by elemental analysis, IR, NMR spectroscopy, and X-ray diffraction. APDE has a 3D wavy layered stacking structure similar to FOX-7. K(APDE) (peak temperature (Tip )=185.6 °C and impact sensitivity (IS)=19.6 J) presents better stability than APDE (tap =133.3 °C and IS=15.7 J). The reasons why the stability of APDE is lower than that of FOX-7 and picryl chloride are analyzed. The detonation velocity (D) and detonation pressure (P) of APDE (8.36 km s-1 and 31.3 Gpa) are close to those of FOX-7 and RDX. The thermal decomposition of K(APDE) is very violent, and its detonation performance (D=9.14 km s-1 and P=38.6 Gpa) is comparable to that of HMX, indicating that K(APDE) has good potential to be a high explosive.

In this paper, we studied the femtosecond laser induced periodic surface structures (fs-LIPSS) formation on LiNbO3:Fe crystal with the assistance of elevated temperature. Uniform deep-subwavelength fs-LIPSS with the period of 190 ± 10 nm was successfully fabricated on crystal surface as the sample temperature was at 1000 °C. And the measurement of Transmission Electron Microscopy showed that fs-laser treated samples remained crystalline. We believed that thermal excitation plays a critical role in the formation of fs-LIPSS. The initial carrier density of LiNbO3:Fe are effectively increased during this process, and high concentration surface carriers are effectively excited by femtosecond laser irradiation, which make great contribution to formation of fs-LIPSS. Moreover, we also found that the doped Fe2+ ions are conducive to the fs-LIPSS formation. The iron doped LiNbO3 crystal with uniform surface structure has great application prospects in related fields, such as on-chip photonic-integrated platforms, nanophotonics, and nanostructures for micro-fluidics.

Bio-foaming during the anaerobic digestion (AD) of the organic fraction of municipal solid waste (OFMSW) is a major cause of unstable reactor operations, especially under high organic loading rates (OLRs). Here, we used two 40-liter anaerobic reactors to deal with the actual organic fraction of municipal solid waste at OLRs of 5 and 7.5 kgVS/m3/d and tried to inhibit bio-foam generation by dosing with Fe0. One of reactors had 400 g of Fe0 added before operation and additional 200 g of Fe0 was added when the operating conditions changed; the other one was the control reactor with no Fe0 dosing. The results show that bio-foam was generated in the control reactor at an organic shock loading of 10 kgVS/m3/d and re-startup at 5 kgVS/m3/d, while the reactor containing Fe0 operated normally. Due to the surfactant attributes of volatile fatty acids (VFAs), the probability of bio-foam generation was positively correlated with the effluent’s degree of surface activity (SA) induced by VFAs, which is a parameter representing the foaming potential. Because VFA biodegradation was enhanced in the reactor with added Fe0, at the position of Fe0 accumulation, the SA was decreased by 49.7–59.2%. Furthermore, the effect of Fe0 dosing on inhibiting bio-foam was evaluated by comparison with traditional commercial anti-foam agents. The results suggest possible reasons for bio-foam generation in OFMSW AD and suggest the reasonable usage of Fe0 to inhibit bio-foam formation.

A dual-function fluorescent probe (Probe 1) was developed for discriminative detection of hydrogen sulfide (H2S) and hydrazine (N2H4). The 2,4-dinitrophenyl moiety was reactive with H2S and the α,β-unsaturated ketone was reactive with N2H4. The discriminative detection of H2S and N2H4 was achieved via the colour change of a solution or test strip of Probe 1-H2S and Probe 1-N2H4. The test strips of Probe 1 reacted with different concentrations of H2S to produce colour changes from colourless to dull red under natural light, and reacted with different concentrations of N2H4 to produce color changes from purple to purplish blue under 254 nm ultraviolet light. Therefore, Probe 1 could be used as a sensor to detect N2H4 and H2S.

Palaeodrainage basin, as an important component of the source-to-sink system, contains critical information on provenance and palaeoenvironment. Previous studies indicate that the scaling relationships of source-to-sink system components generally follow power laws, and channel-belt thickness represents a reliable first-order proxy for the drainage area. In this study, a database of borehole cores and geophysical well logs of the Jurassic coal measures from Saishiteng area in the northern Qaidam Basin was used to reconstruct the palaeogeography, and to identify single-story channel-belts. Three palaeochannels, namely, River A, River B and River C, were identified which were persistent throughout the Dameigou and Shimengou Formations during the Middle Jurassic. The mean channel-belt thicknesses of River A, River B and River C in the Dameigou Formation were 9.8 m, 8.9 m and 7.9 m, respectively, and those in the Shimengou Formation were 7.4 m, 6.2 m and 5.4 m, respectively. We estimate the drainage area of three major rivers by using scaling relationships between drainage area and channel-belt thickness. The drainage areas of River A, River B and River C in the Dameigou Formation were 63.0 × 103 km2, 50.1 × 103 km2 and 37.7 × 103 km2, respectively, and those in the Shimengou Formation were 32.3 × 103 km2, 21.2 × 103 km2 and 15.3 × 103 km2, respectively. The drainage basin lengths of River A, River B and River C in the Dameigou Formation were 300.4 km, 239 km and 180.2 km, respectively, and those in the Shimengou Formation were 154.3 km, 101.3 km and 73.1 km, respectively. For both the Dameigou and Shimengou Formations, River A showed the largest scale, followed by River B and River C succeedingly, which was mainly determined by the stretch direction of provenance in the southern Qilian Mountains. The variations of channel-belt thickness, drainage area and drainage basin length between Dameigou and Shimengou Formations are the response of source-to-sink system to the transformation from extension to compression depression during the Middle Jurassic in the northern Qaidam Basin.