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Drought is a major stress that restricts the growth and development of winter wheat (Triticum aestivum L.), and recovery after drought is the key to coping with adversity. So, we used a meta-analysis to quantitatively evaluate the responses of winter wheat to drought stress and rewatering and investigated the differences caused by several moderators (e.g., stress intensity, treatment durations, growth stages, planting methods, and experimental areas). The results show that drought can cause many negative effects on winter wheat. However, in most cases, rewatering can offset these adverse effects. Winter wheat under short-term or mild stress was less affected, and rewatering can restore it to the control level. Net photosynthetic rate (Pn), transpiration rate (Tr), and stomatal conductance (gs) are sensitive to environmental water change. Drought reduced the quantum yield of electron transport (ΦPSII), with insignificant effects on the efficiency of PSII (Fv/Fm). Additionally, the responses to drought and rewatering also varied with different growth stages. The regreening stage and the anthesis-filling stage are both critical water management periods. Rewatering after the jointing stage had no significant effect on leaf area (LA) and plant height (PH). The drought tolerance and recovery ability of field-grown wheat were better than those of pot-grown wheat. Winter wheat planted on the Loess Plateau was less affected than that on the Huang-Huai-Hai Plain and the Middle–Lower Yangtze Plain. Overall, different moderators may lead to different degrees of responsiveness of wheat to drought stress and postdrought rewatering. This study provides a reference for winter wheat to cope with drought stress and a useful guidance to wheat breeding programs. [ABSTRACT FROM AUTHOR]

Enrofloxacin (ENR) and sulfachloropyridazine combined with trimethoprim (TMP) were commonly used in poultries to treat bacterial infections. In this study, the pharmacokinetics of these antibiotics in four tissues of Taihe black‐boned silky fowls was studied. The results showed that these drugs were absorbed and distributed rapidly, with the highest concentration showing in skin. Meanwhile, ENR and its metabolite ciprofloxacin (CIP) and TMP were depleted slowly, particularly in skin with the elimination half‐lives being 37.1, 36.9, and 72.7 days, respectively. It may be attributed to the abundance of melanin in skin. The dietary risk assessment suggested that the long‐term dietary intakes of ENR, CIP, and TMP showed a considerable threat to human health. Based on the experiment, the withdrawal times of 284 days for ENR + CIP and 159 days for TMP were acquired, which showed that these drugs are not appropriate for the application in Taihe black‐boned silky fowls. [ABSTRACT FROM AUTHOR]

The attractive challenge in green chemistry is exploring novel heterogeneous catalyst system for catalyst-controlled product selectivity for oxidation of olefins. Hence, we proposed efficient and green catalytic methods for the selective synthesis of aldehydes and ketones, the selectivity of the reaction is exclusively dependent on the metals from the catalyst. A series of novel glycosyl pyridyl triazole-platinum (GPT-Pt) complex have been successfully synthesized and fully characterized for the first time. The GPT-Pt catalysts have been applied in the selective oxidative cleavage of alkenes to yield the corresponding aldehydes in the presence of H2O2 as an oxidant in water. With GPT-Pd as the catalyst, the oxidation reaction give the ketones as the main products. Moreover, the catalysts were recovered and reused six times without significant yield decrease. Novel glycosyl pyridyl triazole-platinum (GPT-Pt) complex have been successfully synthesized.The selective synthesis of aldehydes or ketones is exclusively dependent on the metals from the catalyst. Moreover, the catalysts can be separated and reused at least six times with superior activity. [ABSTRACT FROM AUTHOR]

The construction of N-aryl sulfonamides is usually an important reaction in organic synthesis because these compounds are privileged in the structure of many natural products and pharmaceutical molecules. Also, N-aryl sulfonamides are well-known due to their antibacterial, antitumor, and anti-HIV biological activities. Therefore, research on the laboratory synthesis of N-aryl sulfonamides is an important challenge in organic synthesis. In this review, we discussed on methods reported up to now for the synthesis of N-aryl sulfonamides with the goal of stimulating further progresses in this field. We believe that this review will open up a new road for the preparation of pharmaceutically and biologically active sulfonamides. [ABSTRACT FROM AUTHOR]

Actively tunable ultrafast broadband terahertz (THz) polarimetry using a reconfigurable phase‐change material holds great potentials and prospects for the achievement of next‐generation versatile integrated THz components and systems in a variety of THz applications. Here, an optically tunable ultrafast broadband THz polarimetric device (THz‐PoD) composed of a phase‐change material Ge2Sb2Te5 (GST) and a thin mica substrate is demonstrated. This proposed novel THz‐PoD is verified for a frequency range of 0.1–2.5 THz, exhibiting broadband and ultrafast determination of polarization states for linearly polarized THz waves at polarization angles from −90° to 90°. It is shown that optical excitation with ns pulses allows easy and efficient control of the polarimetric properties of such THz‐PoD. The essential role of the GST film in switching the phase transition between the amorphous and crystalline phases is emphasized by the theoretical investigation of the optically tunable ultrafast polarimetric mechanism of the device. This phase transition allows optically changing the THz‐PoD's properties by ns‐pulsed laser in a controlled way to achieve THz polarimetry for linearly polarized THz waves. The combined advantages of this strategy can open up a new and promising way for realizing versatile reconfigurable and integrated THz devices, which may further promote the development of novel THz systems and applications. [ABSTRACT FROM AUTHOR]

Phonon modes of PbTe films grown by molecular beam epitaxy have been studied by micro-Raman scattering. On the as-grown PbTe surface, strong TeO2 phonon vibrational modes were detected, which obscured the observation of the longitudinal optical (LO) phonons of PbTe in early conventional Raman scattering experiments. Existence of a TeO2 layer on the PbTe surface is confirmed by observation with x-ray photoemission spectroscopy. After removal of TeO2 by chemical etching, the LO phonons for PbTe films were unambiguously observed. Misfit strain accommodated in the epitaxial films makes the lattice distorted from cubic structure, which lowers the crystal symmetry and leads to observation of what would normally be Raman inactive LO phonon modes for PbTe. [ABSTRACT FROM AUTHOR]

Abstract: A syringe‐dispersive solid‐phase extraction method was developed for the determination of seven nitroimidazoles and nine steroids in manure‐based fertilizers by ultra‐high performance liquid chromatography with tandem mass spectrometry. Methanol and acetonitrile were used to extract the sample, and mixed dispersive sorbents dispersed in the syringe were used for purification. The extract was separated with an HSS‐T3 column and detected in positive or negative multiple reaction monitoring mode. Under the optimal conditions, the recoveries of the 16 compounds ranged from 70.3 to 112.3% at the four spiked levels (3, 10, 20, and 50 μg/kg) and the relative standard deviations ranged from 1.0 to 12.4%. The limits of detection and quantification were 0.22–0.86 and 0.73–2.87 μg/kg, respectively. This method is simple, fast, and reliable, and can be used to simultaneously screen and determine nitroimidazoles and steroids in manure‐based fertilizers. [ABSTRACT FROM AUTHOR]

An in-cell cleanup pressurized liquid extraction was developed to analyze prohibited antiviral agents in livestock and poultry feces. Extraction and cleanup were integrated into one step. The extraction was performed using methanol-acetonitrile (1:1, v/v) with 0.5% glacial acetic acid at 90 °C, and 0.75 g of PSA was used as the adsorbent during the extraction procedure. Under optimal conditions, the average recoveries for 11 antiviral drugs were 71.5–112.5% at three spiked levels (20, 40, and 100 μg kg −1 ). The detection limits and detection quantitations of the analysis method for the eleven antiviral drugs were 0.6–1.4 and 1.4–4.7 μg kg −1 , respectively. Finally, the method was applied to analyze amantadine, oseltamivir and its metabolites oseltamivir acid in duck feces based on an experiment of an oral dose of two antiviral drugs in duck. The amantadine, oseltamivir and oseltamivir acid can be detected in feces within approximately four weeks after amantadine and oseltamivir were orally administered. The results indicate that the residue analysis in feces is a noninvasive method to monitor inhibited antiviral agents efficiently in livestock and poultry breeding. [ABSTRACT FROM AUTHOR]

An ultrasound/microwave-assisted solid–liquid–solid dispersive extraction method was developed for the determination of 16 pyrethroid insecticides inDendrobium officinale. The extraction and purification were performed in one step. The pyrethroids were extracted with 8:2 acetone:hexane and purified with a mixture of primary secondary amine, Florisil, C18, and graphitized carbon black. The extraction temperature, extraction time, and ultrasound power were optimized. Trans-cyfluthrin-d6was used as the internal standard to improve the accuracy. Under the optimized conditions, the recoveries of the pyrethroids were from 72.2 to 113.9% with the limits of detection between 0.29 and 9.38 µg kg−1. The optimized method was successfully used for the determination of pyrethroids in commercialD. officinalesamples and may allow monitoring pyrethroids in herbal products. [ABSTRACT FROM PUBLISHER]

Under UV irradiation, photo-oxidation occurs on the surface of CdSe quantum dots (QDs), thus modifying their QD optical properties. The influence of size and surface state (SS) emission on the photoluminescence (PL) evolution of CdSe QDs was investigated. Colorimetric study of the CdSe QD emission under UV irradiation indicates that the QD size and SS emission will influence the movement of chromaticity parameters. A photo-corrosion effect reduced the QD size and caused blue shift of the band edge (BE) peak. The irradiation-induced blue shift of QD emission always moves the corresponding chromaticity coordinate counterclockwise in the chromaticity diagram. For CdSe QDs with a dominant SS peak, the different evolution between BE and SS peak under UV irradiation will substantively influence the transformation of emission color: the chromaticity coordinate moved faster when PL increased than that when it decreased. Generally, the emission color of CdSe QDs with relatively large size and weak SS peaks is more stable in irradiation process. [ABSTRACT FROM AUTHOR]

The occurrence of seven trace elements and forty three antibiotics was investigated in manure-based fertilizers from the Zhejiang province of China. These trace elements included copper, zinc, arsenic, chromium, mercury, lead and cadmium. The targeted antibiotics included four groups: sulfonamides, tetracyclines, fluoroquinolones and chloramphenicols. The median amounts of copper, zinc, arsenic, chromium, mercury, lead and cadmium in the analyzed samples were 160, 465, 7.9, 21.2, 0.3, 8.1 and 0.6 mg·kg − 1 , respectively. Seventeen antibiotics were detected. Enrofloxacin was the most frequently detected compound, with a detection rate of 39.3% and concentrations ranging from 6.7 μg·kg − 1 to 4091 μg·kg − 1 . Based on the referred loading rates in agricultural soil, 10% of the collected manure-based fertilizer samples might pose a high potential ecological risk due to the presence of antibiotics. [ABSTRACT FROM AUTHOR]

A one-step ultrasound/microwave-assisted solid-liquid-solid dispersive extraction procedure was used for the simultaneous determination of eight neonicotinoids (dinotefuran, nitenpyram, thiamethoxam, clothianidin, imidacloprid, acetamiprid, thiacloprid, imidaclothiz) in dried Dendrobium officinale by liquid chromatography combined with electrospray ionization triple quadrupole tandem mass spectrometry in multiple reaction monitoring mode. The samples were quickly extracted by acetonitrile and cleaned up by the mixed dispersing sorbents including primary secondary amine, C18, and carbon-GCB. Parameters that could influence the ultrasound/microwave-assisted extraction efficiency such as microwave irradiation power, ultrasound irradiation power, temperature, and solvent were investigated. Recovery studies were performing well (70.4-113.7%) at three examined spiking levels (10, 50, and 100 μg/kg). Meanwhile, the limits of quantification for the neonicotinoids ranged from 0.87 to 1.92 μg/kg. The method showed good linearity in the concentration range of 1-100 μg/L with correlation coefficients >0.99. This quick and useful analytical method could provide a basis for monitoring neonicotinoid insecticide residues in herbs. [ABSTRACT FROM AUTHOR]

Abstract: Carbon dots with unique characters of chemical inertness, low cytotoxicity and good biocompatibility, demonstrate important applications in biology and optoelectronics. In this paper we report the optical properties of pH-sensitive carbon dots with different surface modifications. The as-prepared carbon dots can be well dispersed in water by modifying with acid, alkali or metal ions though they tend to form a suspension when being directly dispersed in water. We find that the carbon dots dispersed in water show a new emission and absorption character which is tunable due to the pH-sensitive nature. It is firstly proved that the addition of bivalent copper ions offers a high color contrast for visual colorimetric assays for pH measurement. The effect of surface defects with different modification on the performances of the carbon dots is also explored with a core–shell model. The hydro-dispersed carbon dots can be potentially utilized for cellular imaging or metal ion probes in biochemistry. [Copyright &y& Elsevier]

White-light emitting (WLE) CdSe quantum dots (QDs) capped with oleic acid (OA) were synthesized and the effects of thermal annealing and photoactivation on the small CdSe QDs in (polymethyl methacrylate) (PMMA) were investigated. A bimodal size-distribution phenomenon induced by annealing at temperatures of ∼200 °C was observed. The phenomenon observed here is different from the result of large CdSe QDs with the similar treatment. The size-dependent property arises from the fact that smaller QDs have a higher surface energy than larger ones. Annealing-induced bimodal size distribution results in a luminescence change of small CdSe QDs. [ABSTRACT FROM AUTHOR]

Abstract: Cubic Mg x Zn1−x O thin films were deposited on amorphous silicon dioxide substrate by reactive electron beam evaporation (REBE) at low temperature (250°C). The characterizations of crystalline structure and morphology of the ternary films demonstrated that the cubic Mg x Zn1−x O films are of highly (001) orientation and have uniform surface. The cubic Mg0.83Zn0.17O film deposited on quartz demonstrates wide band gap (6.45eV) and has very high transparency (>95%) in broad wavelength range from ultraviolet (0.3μm) to mid-infrared light (5.5μm). The refractive indices for the cubic Mg x Zn1−x O decrease as Mg fraction increases. The characters of low optical absorption in broad wavelength range and feasibility of changing refractive index by Mg fraction variation in the ternary Mg x Zn1−x O films could render potential applications in integrated optical devices. [Copyright &y& Elsevier]

High‐speed and highly sensitive infrared photodetectors are regarded as one of the most essential components in modern photonic devices and technology because of constantly emerging application scenarios. In this paper, an ultrafast and extremely low noise mid‐infrared (MIR) photodetector is reported at both room and cryogenic temperatures by leveraging the high‐mobility 2D electron gas (2DEG) at the polar CdTe/PbTe heterostructure interface. The detector simultaneously exhibits a peak detectivity of ≈4.2 × 1011 Jones with rapid response in the order of 10 ns, which is substantially superior to the state‐of‐the‐art 2DEG MIR detectors made of 2D layered materials. The ultrafast response with extremely low noise of the 2DEG photodetector is attributed to the unique band alignment at the interface. The practical infrared imaging application is further showcased using the 2DEG MIR detector by revealing the fine features of a MIR radiation target. This work highlights the promising prospect of utilizing the unique 2DEG interface in the field of high‐speed and highly sensitive MIR detection. [ABSTRACT FROM AUTHOR]

In this work, the fabrication of the CuO on ZnCdS as a heterojunction nanocomposites were conducted by hydrothermal method and the synthesis method was confirmed by the XRD, XPS, EDS, UV–vis spectrum analysis. The CuO/ZnCdS was used as a photocathode in the bio-photoelectrochemical system (BPES) for tetracycline (TC) degradation under solar irradiation. The CuO/ZnCdS photocathode indicated substantial photocatalytic efficiency for TC degradation, due to the fast separation and transfer of photogenerated carriers. The ESR test evaluates the mechanism of degradation, and shows that ·OH, and ·O 2 − were contributed to TC degradation. The TC degradation was 1.59 times higher than the unilluminated process (98.72% vs 61.71). The photocatalysis test shows that the TC was degraded about 90.5% in 1.5 h. Then, the synthesized CuO/ZnCdS nanocomposites were studied for the biological application such as antifungal activities. CuO/ZnCdS nanocomposites depicted substantial antimicrobial activity versus Candida-albicans by in vitro process. Therefore, this study suggests the novel system for the antibiotics degradation, and as antifungal application. [Display omitted] • Efficient CuO/ZnCdS photocathode was developed for BPESs. • The O 2 −, OH and ·CO 3 − promoted TC removal in BPESs with NaHCO 3. • Pseudomonas and Acinetobacter capable to degrade TC were detected on bioanode. • Possible TC degradation mechanism and pathways in the BPES were proposed. • CuO/ZnCdS nanocomposites depicted substantial activity versus Candida-albicans. [ABSTRACT FROM AUTHOR]

[Display omitted] • Development of magnetic β-ketoenamine COF (Tp-DHBD M−COF). • Room-temperature mechanochemical method simplified the synthesis of M−COF. • A COF-MSPE method was developed to detect residue-prone OPEs in water environment. • The method showed good extraction efficiency (>60 %) for 12 OPEs at 1–10 ng/mL. In this work, Fe 3 O 4 /Tp-BHBD β-ketoenamine covalent organic framework (COF) was rapidly prepared. Then, it was used as magnetic solid phase microextraction (MSPE) adsorbents for the adsorption and determination of organophosphate ester (OPE) residues in surface water coupling with liquid chromatography-tandem mass spectrometry. The results of material characterization tests confirmed the generation of magnetized COF. The adsorption process was optimized by Box-Behnken Design and one-factor optimization experiments. After five use cycles, Fe 3 O 4 /Tp-DHBD still achieved good adsorption and high recovery. Under the optimal conditions, the developed Fe 3 O 4 /Tp-DHBD COF-MSPE-HPLC-MS/MS method obtained good linearity for 12 OPEs within 0.25–50.0 ng mL−1 and the limit of detection of 0.02–0.18 ng mL−1. The relative standard deviations were less than 8.6 %. Rapid detection and analysis of three samples from wastewater treatment plant showed that the recoveries of most of target OPEs at different spiked concentrations ranged from 62.0 % to 116.9 %, 60.9 %-115.1 %, and 60.4 %-112.9 %, respectively. In general, the established COF-MSPE method can provide convenient and satisfactory purification for OPEs compounds in surface water by adsorption and desorption, which is promising for specific applications. [ABSTRACT FROM AUTHOR]

Organometal halide perovskites (PVKs) have demonstrated their potential in photovoltaics in terms of higher photovoltaic efficiency, aiming to achieve the Shockly-Quieser limit of a single-junction solar cell. Understanding the photo-optical and structural properties of PVKs is crucial to further improving their photovoltaic efficiency. Defects-free PVKs with a suitable energy bandgap (E BG ∼ 1.34 eV) are desirable to capture most of the solar radiations; however, the E BG of the state-of-the-art PVKs is not the ideal one. Compositional engineering offers E BG tunability but decreases carrier lifetime and increases material instability. The application of hydrostatic pressure is a green route, which initiates structural changes in the PVKs and tunes their E BG , leading to the emergence of interesting material properties, including piezochromism, metallization, photoresponsivity, and structural stability. Therefore, understanding the interplay between pressure-induced electronic and structural changes is crucial. Herein, the pressure-induced modifications in structural and optoelectronic properties are elaborated. Particularly, pressure-induced properties in single crystals, lower-dimensional PVKs, and all-inorganic PVKs are comprehended. Moreover, PVK amorphization and strain-induced properties of various PVK materials are also summarized. The review is concluded with an outlook discussing the challenges associated with the pressure induction on PVK material and our perspective to resolve these issues and future work. [ABSTRACT FROM AUTHOR]

Abstract: Radix Ophiopogonis and Radix Liriopes are two widely used herbal medicines and functional foods with similar pharmacological activities and clinical efficacies. In order to figure out whether phytoequivalence of species leads to therapeutic equivalence and consistency, in this study, a novel sensitive and selective high performance liquid chromatography-tandem mass spectrometric method (HPLC-MS/MS) has been developed for the simultaneous analysis of 11 bioactive components (6 steroidal saponins and 5 flavonoids) and then was applied for comparing in Radix Ophiopogonis and Radix Liriopes from different habitats. Separation was performed using a C18 analytical column with gradient elution of acetonitrile and 0.3‰ acetic acid (v/v) at a flow rate of 0.8mL/min. Multiple-reaction monitoring (MRM) scanning was employed with switching electrospray ion source polarity between positive and negative modes in a single run. All calibration curves showed good linearity (r2 >0.9915) within the test ranges. The intra-day and inter-day precision for 11 analytes were less than 3.7% and 4.2%, respectively. The recoveries were between 95.3% and 106.7%. Fifty-three batches of commercial samples from different sources were analyzed using the developed method. Hierarchical clustering analysis (HCA) and content analysis were performed to differentiate and classify the samples. The results demonstrated that steroidal saponins were the major components in both Liriopes species, and a low content of flavonoids could become an important symbol of distinction between Ophiopogonis and Liriopes. The developed method could successfully differentiate between Ophiopogonis and Liriopes. [Copyright &y& Elsevier]

[Display omitted] • • The flavor active compounds were confirmed. • • Enzymes, microbes, and flavors were quantitatively analyzed. • • Aspergillus and Staphylococcus were the core functional microorganisms. • • The formation pathways of flavor were revealed. • • Fermentation time can be shortened without affecting the quality of koji. Based on the widespread application and under-research of mechanized preparation Cantonese soy sauce koji (MP), absolute quantitative approaches were utilized to systematically analyze the flavor formation mechanism in MP. The results indicated that the enzyme activities increased greatly during MP fermentation, and 4 organic acids, 15 amino acids, and 2 volatiles were identified as significantly different flavor actives. The flavor parameters of MP4 were basically identical to those of MP5. Furthermore, microorganisms were dominated by Staphylococcus , Weissella , and Aspergillus in MP, and their biomass demonstrated an increasing trend. A precise enumeration of microorganisms exposed the inaccuracy of relative quantitative data. Concurrently, Staphylococcus and Aspergillus were positively correlated with numerous enzymes and flavor compounds, and targeted strains for enhancing MP quality. The flavor formation network comprises pathways including carbohydrate metabolism, lipid metabolism and oxidation, and protein degradation and amino acid metabolism. In summary, the fermentation period of MP can be substantially shortened without compromising the product quality. These findings lay the groundwork for refining parameters in modern production processes. [ABSTRACT FROM AUTHOR]

Mycotoxins co-contamination in soybean poses great risks to human health, however, due to their diverse structures, it is difficult to simultaneously extract and detect these multi-mycotoxins. By incorporating modification of hydrophilic carboxyl groups with the hydrophobic properties of covalent organic frameworks, a stable cubic carboxyl-functionalized magnetic amide-linked covalent organic framework were fabricated, characterized and utilized as adsorbents for magnetic solid phase extraction (MSPE) of eleven frequently detected mycotoxins from soybeans followed by HPLC-MS/MS analysis. The key MSPE parameters were screened using the Plackett-Burman design and optimized with the Box-Behnken design for response surface methodologies. Under the optimal experimental conditions, the linear range was 0.2–50 μg/kg, the limits of detection were 0.1–1.4 μg/kg. The established method was applied for the soybean analysis with satisfactory recoveries (70.8–108.3%) and precision (intra- and inter-relative standard deviations of 2.1–9.2% and 1.6–11.1%, respectively). With proper modification, this method may have great application potential for simultaneously analyzing and monitoring the multi-mycotoxin contamination in foods to ensure consumer safety and public health. • Fe 3 O 4 @COF–COOH was facilely fabricated as MSPE adsorbent. • Fe 3 O 4 @COF–COOH has satisfactory extraction performance towards multi-mycotoxins. • Multivariate experimental designs were used to screen and optimize the parameters. • Simultaneous determination of 11 mycotoxins in sobeans was developed. [ABSTRACT FROM AUTHOR]

Benefit from high quantum efficiency and low dark current, blocked-impurity-band (BIB) detectors have been the state-of-the-art choice in astronomy science. The temperature extrinsic-response-reduction mechanism in BIB detectors is vague for lack of pertinent research. We fabricated Si:P BIB detectors with a remarkable blackbody detectivity of 2 × 1012 cm · Hz1/2/W at 4 K, 2 V (blackbody 800 K). Both varying temperature optoelectronic characterization and calculated results overturn the common standpoint that focuses on ionization proportion. Instead, solid evidence indicates that the increase in the negative charge density according to temperature significantly influences the width of the depletion region until it totally vanishes beyond 20 K. The mechanism enriches the design thoughts of the BIB detector for improving its performance. [ABSTRACT FROM AUTHOR]

Summary: Background: As the prevalence of hepatitis steatosis (HS) increases, the prevalence of HS among those with chronic hepatitis B (CHB) may also be increasing but data on the effect of HS on CHB disease progression are lacking. Aims: To determine the prevalence of HS in CHB and associated factors, prevalence of fibrosis and its association with HS. Methods: Two researchers independently searched the literature and extracted data. We included full‐length original articles of adults with CHB that evaluated. Prevalence estimates were pooled using a random‐effects model. Associations between HS and fibrosis were assessed by pooled odds ratios (ORs) or mean differences (MD). Results: Of the 2821 records screened, 54 eligible studies (28 648 patients) were analysed. The pooled prevalence of HS in CHB was 32.8% (95% CI, 28.9‐37.0) with higher prevalence in men and obese patients. Older age, male sex and metabolic factors were associated with HS while an inverse association was observed between HS and HBeAg (OR 0.82, 95% CI, 0.75‐0.91) and HBV DNA levels (MD −0.38, 95% CI −1.16‐−0.42). The pooled prevalence of significant fibrosis (≥F2 or ≥F3) was similar between patients with CHB with or without HS (40.1% vs 42.22%, P = 0.68). HS was not significantly associated with fibrosis (pooled OR 0.87, 95% CI 0.54‐1.39, 20 studies, 6232 patients). Conclusions: Approximately 30% of patients with CHB had HS, which was positively associated with male sex, diabetes and metabolic factors, and was negatively associated with HBeAg and HBV DNA. HS was not significantly associated with increased fibrosis. [ABSTRACT FROM AUTHOR]

We propose by exploring CdTe/PbTe single heterojunctions (SHs) that the abnormal enhancement of mid-infrared light emission from CdTe/PbTe heterostructures is due to coupling with surface plasmons. It is discovered that the observed intense mid-infrared luminescence in the SHs comes from the inherent polar interface character and coupling of surface plasmons localized at the metallic CdTe/PbTe interface to light emitted from the narrow gap PbTe. The finding offers an approach to manipulate mid-infrared light and to fabricate improved mid-infrared optoelectronic devices. [ABSTRACT FROM AUTHOR]

• ZIF-8@GO was synthesized and applied as thin-film microextraction coating. • Thin-film microextraction with UPLC-MS/MS for antibiotics detection in honey was constructed. • Automated preparation offers simultaneous extraction of up to 96 samples per run. A high-throughput method using a new ZIF-8@GO thin-film microextraction coating was established for determining macrolides and lincosamides in honey. The coating preparation parameters (ZIF-8@GO synthesis conditions, coating material proportions, dipping time) and analysis parameters (sample diluent solvent, adsorption and desorption conditions using the ZIF-8@GO coating) were optimized. The optimized parameters were: diluent solvent sodium carbonate/sodium bicarbonate buffer solution (pH 9), adsorption time 45 min, desorption time 5 min, desorption solvent 45:40:15 v/v/v methanol/acetonitrile/water. The extracted targets were determined by ultra-high performance liquid chromatography tandem mass spectrometry. The recoveries of 10 analytes were 67.5–107.2% and the detection and quantification limits were 0.1–0.4 and 0.4–1.4 μg/kg, respectively. The method could analyze 96 samples per run. The minimal manual time and effort is required since the bulk of the sample processing is fully automated. It was a useful and efficient method for monitoring drug residues and was successfully used to analyze real samples. [ABSTRACT FROM AUTHOR]

The research on novel terahertz (THz) devices with high performance is in rapid ascent in order to promote applications of THz technology. In this paper, we propose a broadband, optically transparent and highly flexible multispectral beam splitter based on Ag nanowires/graphene (ANWG) composite film on polyethylene terephthalate film substrates. The properties of the ANWG-based beam splitters are investigated, which exhibit a broadband THz reflectance of about 90%, a high optical transmittance of over 86% in the visible range, and excellent mechanical flexibility. The THz experimental result of the ANWG-based beam splitter is close to those of numerical simulations using a theoretical model. In comparison with conventional THz beam splitters, the ANWG-based beam splitter possesses excellent light-splitting performances for both transmitting visible light and reflecting THz radiation, and the device can significantly improve the overall performance of THz optical systems. Moreover, the device can be effectively applied in the visible/infrared imaging systems to implement multispectral imaging. Our concept provides a promising route for realizing compact hybrid optical systems, and it has great potential for commercial applications. [ABSTRACT FROM AUTHOR]

The existence of bio-accumulative lead hinders the commercialization of optoelectronic applications of Pb-based halide perovskites (PVKs). Therefore, researchers are seeking for comparative lead-free PVKs. Owing to the identical electronic configuration with Pb, Bi-based PVKs are proved to be one of the most promising candidates. Because strain is widely existed altering materials' characteristics, it is crucial to study the influences of strain on the Bi-based PVKs. Our theoretical work investigates the strain influences on two kinds of Bi-based PVKs, i.e., Cs3Bi2Br9, and Cs2BiAgBr6. It is observed that both the tensile and compressive strains effectively change the crystal structures and the bandgaps, i.e., enlargement under tensile strain while shrinkage under compressive strain. Simultanously, the absorption spectra of these PVKs are also discussed. The strain study of Bi-based PVKs will offer guidance to the further development of lead-free PVKs. [ABSTRACT FROM AUTHOR]

We fabricate Ge:B-blocked impurity band (BIB) far-infrared detectors using near-surface processing techniques. The current–voltage (I – V) characteristics and the energy band structure are investigated. It is found that there are three interfacial barriers in Ge:B BIB detectors due to the bandgap narrowing effect. The barrier height can be adjusted by changing the doping concentration in the contact region of BIB detectors. A new dark-current-blocking mechanism is proposed that the interfacial barriers can block the transport of carriers at low temperatures. Moreover, the greater the barrier height, the stronger the blocking effect. Utilizing this new blocking mechanism, the I – V characteristics of Ge:B BIB detectors can be better explained. By increasing the barrier heights, the dark current is reduced significantly, almost six orders of magnitude within a certain voltage range, and the working temperature is increased from the usual 4.2–10 K, which is of great significance for extending the service life of BIB detectors on outer space observation platforms. Our findings will help to better design BIB detectors and improve their performance. [ABSTRACT FROM AUTHOR]

Blocked impurity band (BIB) detectors play an important role in astronomical detection from the mid-infrared to THz region. We demonstrated the field dependence of the photoresponse in BIB detectors using both experimental results and theoretical calculations. It was found that there is a gain operation region between the saturation voltage of the photocurrent and the breakdown voltage of the dark current. The photoconduction gain in the gain operation region is several orders of magnitude larger than that in the other voltage range. Considering the field-assisted thermal ionization process and the photon-assisted impact ionization process, the gain operation mode can be well explained. Utilizing the gain operation mode, Ge:B BIB detectors can even detect the objects with a temperature as low as 10 K. We provide a theoretical basis to optimize BIB detectors and further improve their detection performance. [ABSTRACT FROM AUTHOR]

• Dodecylammonium chloride assisted the formation of compact lead-free perovskites films. • The crystallinity and stoichiometric defects of the films are significantly improved. • Enhanced optical absorption, photoluminescence, and extended carrier lifetime is achieved. • Solar cell device exhibited a highest PCE for the solution-processed Cs 3 Bi 2 I 9 -based devices. • Photovoltaic device demonstrated an enhanced environmental stability in the ambient air. Bismuth is considered as one of the most promising candidates to replace Pb in the organo-lead halide perovskite, a classical material for various optoelectronic applications. When utilized in a photovoltaic cell, the performance of the cell drops due to deterioration in the absorber film and the changes in its crystal structures. In this work, a small amount of dodecylammonium chloride, C 12 H 25 NH 3 Cl (DCl) is added into Cs 3 Bi 2 I 9 (CBI), resulting in a pinhole-free high-quality perovskite (PVK) film via a single-step solution processability, also confirmed by FTIR and XPS analyses. Structural, optical, and microscopic analyses showed that the quality, surface features, and crystallinity of the CBI films are significantly improved by adding DCl. The prepared films are successfully demonstrated in a solar cell and exhibited considerably improved photovoltaic (PV) characteristics (V OC by ~47%, J SC by ~33%, FF by 13%, and PCE by 115%) over pure CBI-based devices. Moreover, the PV device retained more than 95% of its initial PCE in the ambient laboratory environment (relative humidity 55±5%). To the best of our knowledge, this is the highest PCE along with extended environmental stability reported for solution processed CBI-based perovskite solar cells. [ABSTRACT FROM AUTHOR]

Two-dimensional crystals-based surface-enhanced Raman scattering (SERS) substrates are a research hot spot in the realm of chemistry and biology. Herein, a novel hybrid substrate based on AuNPs/GaTe/Au-film is proposed and fabricated for SERS activity. Finite-difference time-domain numerical simulations demonstrate that the plasmonic coupling in the hybrid structure, particularly the LSPs coupling of AuNPs and Au-film, promotes an enhanced electric field and consequently, greatly enhances the Raman activity. Impressively, the enhancement factor of 3 × 105 and the limiting detection concentration of 10−14 M have been achieved for the rhodamine 6G molecules, which are equivalent to the best results achieved from the patterned graphene substrates. Due to its simple structure, cost-effectiveness, good uniformity, reproducibility, and stability, it is expected that such a SERS substrate will open up a new way toward the ultrasensitive detection of molecules. [ABSTRACT FROM AUTHOR]

Two-dimensional phenylethylammonium (PEA, C8H9NH3) Bi–Ag double perovskite (PEA)4BiAgX8 (X = Br, I) microplatelets are synthesized for the first time via a facile self-assembly recrystallization method. Absorption spectra of microplatelets exhibit direct bandgaps and different halide compositions show distinct morphologies and bandgap tunability. Field-effect transistors based on a single (PEA)4BiAgBr8 microplatelet display a p-type semiconducting behavior. [ABSTRACT FROM AUTHOR]

The remarkable optoelectronic properties and considerable performance of the organo lead‐halide perovskites (PVKs) in various optoelectronic applications grasp tremendous scientific attention. However, the existence of the toxic lead in these compounds is threatening human health and remains a major concern in the way of their commercialization. To address this issue, numerous nontoxic alternatives have been reported. Among these alternatives, bismuth‐based PVKs have emerged as a promising substitute because of similar optoelectronic properties and extended environmental stability. This work communicates briefly about the possible lead‐alternatives and explores bismuth‐based perovskites comprehensively, in terms of their structures, optoelectronic properties, and applications. A brief description of lead‐toxification is provided and the possible Pb‐alternatives from the periodic table are scrutinized. Then, the classification and crystal structures of various Bi‐based perovskites are elaborated on. Detailed optoelectronic properties of Bi‐based perovskites are also described and their optoelectronic applications are abridged. The overall photovoltaic applications along with device characteristics (i.e., VOC, JSC, fill factor, FF, and power conversion efficiency, PCE), fabrication method, device architecture, and operational stability are also summarized. Finally, a conclusion is drawn where a brief outlook highlights the challenges that hamper the future progress of Bi‐based optoelectronic devices and suggestions for future directions are provided. [ABSTRACT FROM AUTHOR]

Organometal halide perovskites (OMHPs) have shown promising applications in solar cells, light-emitting diodes, and photodetectors. However, besides the toxic lead, the intensive usage of organic solvents during their fabrication could induce severe environmental pollution. Therefore, green-solvent fabrication of OMHPs is highly desirable but extremely challenging. Herein, we report aqueous phase fabrication and conversion of laurionite-type Pb(OH)Br into CH3NH3PbBr3. The prepared CH3NH3PbBr3 crystals show prominently enhanced environmental and thermal stability compared to those prepared in organic phases. To demonstrate the application of the prepared CH3NH3PbBr3, a resistive switching memory device (ReRAM) is fabricated. The ReRAM devices exhibit good bipolar non-volatile characteristics that can remain unchanged for more than 30 days under ambient conditions. We believe that the aqueous phase-based green fabrication process of OMHPs will not only greatly alleviate the environmental pollution during or after their commercialization process, but will also provide a new concept in stabilizing and improving the performance of OMHP-based devices. [ABSTRACT FROM AUTHOR]

A CdTe/PbTe heterojunction (HJ) yields two-dimensional electron gas (2DEG) with a high electron density and mobility. Ultrahigh-speed and room-temperature operating mid-infrared photodetectors are developed with the 2DEG. The photoresponse of the detectors originates from the intrinsic response of PbTe by virtue of the conduction-band and valence-band alignment of the HJ. The extremely short rise and decay photoresponse time demonstrate a major advantage of the 2DEG. At λ = 3.0 μm and a bias voltage of 100 mV, the responsivity and detectivity reach 0.94 A/W and 2 × 1010 Jones, respectively. The excellent performance of the detectors renders promising applications in novel mid-infrared frequency detection systems. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to test whether the implementation of an enhanced recovery after surgery (ERAS) protocol for patients undergoing elective cesarean delivery has a positive impact on the postoperative status of the patients in terms of pain management, hospital stay, hospitalization costs, and adverse reactions.Methods: Patients who underwent elective cesarean delivery were randomized into two groups - ERAS group and control group - and the groups were managed with the ERAS protocol and traditional protocol, respectively.Results: Compared to the control group, the ERAS group had significantly fewer patients with intraoperative nausea, pain of visual analog scale (VAS) scores, and VAS grade >3 during rest in the first 24 h and during motion in the first 24 and 48 h after surgery. There were no intergroup differences in the requirement of extra analgesics, the incidence of vomiting, shivering, hypotension, postoperative nausea, and pruritus. None of the patients in either group had postoperative vomiting. Patient satisfaction rated as per the VAS was significantly higher in the ERAS group than in the control group. The total length of stay, postoperative length of stay, and the cost of anesthesia in both groups were comparable. Further, the average daily hospitalization cost was significantly lower in the ERAS group than in the control group.Conclusion: The ERAS protocol shows promise and appears to be worthwhile for widespread implementation among patients undergoing elective cesarean delivery; it was found to be beneficial in reducing the postoperative pain, incidence of intraoperative nausea, and average cost of hospitalization and also improved patient satisfaction. [ABSTRACT FROM AUTHOR]

A high‐throughput method based on ultrasonic‐assisted extraction, 96‐well plate thin‐film microextraction was established to determinate 18 antibiotics in animal feed. In this method, the extraction was implemented by ultrasonic‐assisted extraction for 30 min with disodium ethylenediaminetetraacetic acid‐McIlvaine buffer (pH 5) containing 6% sodium chloride w/v, purified by thin‐film microextraction and combined with 96‐well plate system to improve the efficiency. Optimization of thin‐film microextraction conditions was performed by methods of single factor and response surface, and finalized as: condition time: 20 min; adsorption time: 55 min; washing time: 5 s with water; desorption time: 30 min with acetonitrile/water (8:2, v/v) containing 0.1% formic acid v/v. Evaluation of different extractive phases showed that polystyrene‐divinylbenzene‐polyacrylonitrile was the optimum coating. The analysis was performed by ultra‐high performance liquid chromatography with tandem mass spectrometry. Recovery, inter‐ and intraday precision, linearity, limit of detection, and quantitation were evaluated. The average recoveries of 18 antibiotics were 66.6–93.5% at three spiked levels, intraday precision was 1–8.4%, and interday precision was 3.0–16.4%. The linearity was good for r2 > 0.99. Limits of detection and quantification were found in the range of 1–14 and 4–48 µg/kg, respectively. [ABSTRACT FROM AUTHOR]

• Ambient environment synthesis of the hybrid perovskites films and solar cells. • Addition of Dodecylammonium for the 1st time into the triple cation perovskites. • HPVKs thin films showed stablility for 50 days in relative humidity well above 50%. • HPVKs thin films showed stablility to high thermal stress of 85 ℃ for 24 h. • Solar-cell made of HPVKs yielded a PCE of 5%. • PCE of the solar cell retained up to 64% for 9 days in RH > 50% and 85 ℃. Owing to their high efficiency and extended environmental stability, hybrid 2D/3D-perovskites (HPVKs) are gaining an increasing interest in the field of organometal halide perovskite solar cells (PSCs). In HPVKs, the 3D component acts as an active material, where its 2D-counterpart provides protection against environmental factors. Here in, we add dodecylammonium-chloride (DACl) into the precursor solution of 3D-perovskites (FAMAPbI 3) to achieve HPVKs. The formation of HPVK is confirmed by XRD, optical absorption, and Fourier-transform infrared (FTIR) spectroscopies. The structural and optical analysis affirmed that in the case of HPVKs, not only the crystallinity of perovskites is improved significantly but also a variation in its structural properties and optical bandgap have occurred. It is also observed that the surface morphologies of HPVK films are considerably improved with the incorporation of DACl. A minute amount of CsI is also added into the precursor solution of HPVKs, which further assist the formation of HPVKs and consequently causes a significant increase in the carrier lifetime. Finally, a solar cell made of HPVKs shows an improved PCE than pure 3D-perovskites. All HPVKs films and solar-cells are prepared in the ambient humidity and found to be more hydrophobic and stable, not only under relative humidity >50% but also under high thermal stress of 85 ℃. [ABSTRACT FROM AUTHOR]

Two‐dimensional electron gases (2DEGs) confined to quantum wells trigger rich emergent phenomena and serve as a host for high‐speed electronics. 2DEG in PbTe/CdTe heterostructure was predicted to be Dirac electrons and confirmed by recent experiments. Here, we demonstrate the manipulation of electrical transport properties of this 2DEG with extremely high mobility and unique electron structure by ionic liquid‐gating. The extreme capacitance of carrier modulation enables to tune the band structure. With a change of the gate voltage, the Fermi level moves to the conduction band and crosses the Dirac Point, leading to the shift of quantum oscillation. Our results may offer new insight toward electronic application with on‐demand properties. [ABSTRACT FROM AUTHOR]

Despite their facile synthesis and unprecedently increased power conversion efficiency, there is a dark side of organo-metal halide perovskites solar-cell i.e. their intrinsic environmental instability. A little moisture, harsh ultraviolet-light, and slightly higher thermal stress demolish it quickly into its constituents. A solution to these instability issues is a prerequisite to commercialize this next-generation solar-cell technology. To understand the degradation mechanism in perovskites, different models have been proposed. Similarly, to prevent them from environmental hazards, various strategies have been adopted. For instance, 2D-perovskites are introduced as a stable alternative to their 3D-counterparts. However, due to their wider bandgaps, 2D-perovskites failed to compete with 3D-perovskites in the race of power conversion efficiency. Therefore, a hybrid 2D/3D-perovskites are introduced which brought together, the high power conversion efficiency of 3D-perovskites and extended environmental stability of their 2D counterparts. The first section of this review discusses in detail about the proposed mechanisms behind the perovskites decompositions due to environmental factors including; humidity, radiation, and thermal stress. While, the second part summarizes several strategies adopted to prevent perovskites degradation; particularly, the strategy of shielding 3D-perovskites with its 2D counterpart, which is the most promising one. Furthermore, this review provides details of the overall progress been made in the field of pure-2D, quasi-2D, and hybrid-2D/3D perovskites solar-cells. In the end, a brief outlook on the challenges remaining in the way of commercialization of perovskites solar-cells and our opinion to their possible solutions is given. • A little moisture, UV-light, and slightly higher thermal stress quickly demolish perovskite (PVK) into its constituents. • A comprehensive understanding of the PVK-decomposition mechanism is a prerequisite to cure them accordingly. • Numerous strategies have been adopted to overcome the environmental instability of perovskites solar-cells (PSCs). • Hybrid 2D/3D-PVKs are proved to be the best remedy to protect PSCs from environmental influences. [ABSTRACT FROM AUTHOR]

• The simulation predicts that the extraordinary transmission occurs. • The photoresponses of the THz detectors integrated with PHS are modulated. • The photoresponse of the reference detector without PHS covers a broad scope. • It demonstrates the potential of our device in multi-spectral THz detection. We predict an extraordinary transmission (ET) of a periodic hole structure (PHS) by simulating plasmonic properties using finite difference time-domain Solutions. The ET effect is used to modulate the photoresponse by integrating the PHS into silicon-based blocked-impurity-band (BIB) terahertz detectors. The measured photoresponses of the experimentally realized PHS + BIB detectors confirm the tunability of photoresponses. Moreover, the electromagnetic field distribution is also simulated, which reveals that the prominent modulation effect originates from a strongly confined electromagnetic field. The response away from the resonance wavelength is largely suppressed. This work demonstrates the potential of our device in multi-spectral terahertz detection. [ABSTRACT FROM AUTHOR]

Fluorescent semiconducting conjugated polymer nanoparticles (CPNs) are promising candidates for enhanced luminescent devices and bioimaging. The key aspect of all fluorescent materials is their high radiative yield. Combination of CPNs with metal nanoparticles (MNPs) is one of the ways to increase their fluorescent yield. Most of such combinations are introduced in the forms of sophisticated core–shells and thin films or layers. Herein, we synthesized CPNs of poly[2-methoxy,5-(2′-ethylhexyloxy)-1,4-phenylenevinylene] (MEH-PPV) and silver nanoparticles (AgNPs) in aqueous solution in the form of metal–polymer nanocomplexes (MPNCs), which are not only easily achievable but also show significantly enhanced optical absorption and luminescence properties. To synthesize MPNCs, AgNPs with different molar ratios were added to a colloidal solution of CPNs. The adsorption of AgNPs on the surfaces of the CPNs was confirmed by transmission electron microscopy and UV-VIS absorption spectroscopy. Fluorescence and optical absorption spectroscopies revealed a substantial increase in the optical absorption and photoluminescence (PL) intensity of the MPNCs. It was observed that at optimum concentrations of AgNPs and CPNs in the colloidal solution of MPNCs, the PL intensity is enhanced by ∼11 fold. The increase in PL intensity is attributed to the energy transfer from AgNPs to CPNs via near-field-coupling and electric field enhancement in the nanogaps present among the adsorbed AgNPs on the surfaces of the MPNCs, which is confirmed by finite difference time domain (FDTD) simulations. Since the MPNCs as well as their ingredients were prepared in aqueous solutions, we believe that such nanocomplexes could find use not only in enhanced fluorescent devices but also in therapeutics and diagnostics. [ABSTRACT FROM AUTHOR]

Abstract: Topological materials boast exotic metallic surface states with linear dispersion and spin‐momentum locking, which makes them potential candidates for dissipationless electronic and spintronic devices. Here, it is theoretically predicted that intrinsic Te antisite defects (TePb) in the narrow‐gap semiconductor PbTe induce a band inversion, turning it into a topological crystalline insulator (TCI). To experimentally verify the exotic properties, TePb antisites are introduced into PbTe crystals via nonstoichiometric growth by molecular beam epitaxy. Semimetallic resistivity and distinct quantum oscillations are observed on the TePb doped PbTe. Most importantly, a π Berry phase is unambiguously revealed by a Landau index analysis, demonstrating the Dirac fermion nature of the topological surface states. The discovered TCI nature in TePb doped PbTe is further explored using magneto‐transport measurements under external pressure, and the theoretical calculations of band structures with applying pressure indicate a pressure‐induced Lifshitz transition. Besides, it is proposed that the contribution of bulk states to transport can be reduced by enlarging the inverted gap with strain. [ABSTRACT FROM AUTHOR]

Mid-infrared blocked-impurity-band (BIB) photonic detectors are developed by sulfur (S) ions implantation into germanium (Ge) crystal. The detectors demonstrate wide photoresponse spectra ranging from 2 to 10 μm with peak response at about 6 μm. We characterize photocurrent spectra of two operating modes, forward bias mode (FBM) and reverse bias mode (RBM), and find that RBM has a lower optimum bias but a bigger photocurrent. Effect of different blocking layer (BL) length on photocurrents for the two operating modes is studied. When BL length increases, the ratio of the relative photocurrent under RBM to that under FBM at respective optimum bias enlarges. The slope of the electric field profile in BL leads to the differences of optimum bias and maximum photocurrent between two modes. The electric field strength in AL under RBM strengthens as BL length increases, resulting in larger photocurrent for longer BL. [ABSTRACT FROM AUTHOR]

In recent years CdTe thin film solar cells (SCs) have demonstrated promising market application foreground. However, a relatively large gap between the achieved SCs efficiencies and the theoretically predicted maximum efficiency still exists. In particular, the open circuit voltage (V oc ) of the CdTe thin film SCs could be further increased, which is limited by high-work-function of CdTe. In this work, p-type narrow-gap SnTe thin films are proposed as a buffer layer in the back contact of CdTe SCs. The band alignment at SnTe/CdTe interface renders a small valance band offset, which expedites hole transport from the CdTe absorber to the hole electrode and improves the Ohmic contact for CdTe. With the insertion of a SnTe single buffer layer at the back contact, a Cu-free CdTe SC has been developed, which displays the same cell efficiency as the traditional cells using Cu x Te as the back contact. The V oc of cells with ZnTe: Cu/SnTe double-layer at back contact is notably higher than the CdTe SCs fabricated with Cu x Te or ZnTe: Cu single-layer at the back contact. Furthermore, accretion of hole concentration is also demonstrated by the diffusion of Sn in the CdTe absorber layer. This work shows the potential to improve CdTe SCs by using a narrow-gap IV-VI compound semiconductor. [ABSTRACT FROM AUTHOR]

Abstract: An analytical method for the simultaneous determination of 13 mycotoxins in feed by magnetic dispersive solid‐phase extraction combined with ultra‐high performance liquid chromatography and tandem mass spectrometry was developed. The samples were extracted with acetonitrile/water (80:20, v/v, containing 3% acetic acid), and separated by centrifugation after salting‐out, and then treated with magnetic adsorbents to remove interferences. The separation of target mycotoxins was performed on an ACQUITY UPLC HSS T3 column using a mobile phase consisting of 1 mmol/L ammonium acetate with 0.1% formic acid and methanol by gradient elution. Good linearities for the 13 mycotoxins were achieved with correlation coefficients over 0.99, and the recoveries of mycotoxins were in the range of 89.3–112.6% at spiking at levels of 5, 20, and 100 μg/kg, with relative standard deviations of 0.9–10.4%. Based on the functional magnetic materials (MDN@Fe3O4, PSA@Fe3O4, ZrO2@Fe3O4) applied in dispersive solid‐phase extraction, the pretreatment process is more convenient and it is beneficial to reduce the experimental cost by reusing the recycled magnetic materials. It is a simple, rapid, and environmentally friendly analytical method for the determination of mycotoxins in feed. [ABSTRACT FROM AUTHOR]

• A simple and rapid extraction method for ten common mycotoxins in maize was proposed. • Magnetic Fe 3 O 4 /COF-TpBD adsorbents was facilely prepared. • Fe 3 O 4 /COF-TpBD exhibited excellent extraction ability for ten common mycotoxins. • The developed MSPE procedure required only 5 mg of adsorbent. A simple, rapid and sensitive vortex-assisted magnetic solid phase extraction (MSPE) method using core–shell structured magnetic covalent organic frameworks (Fe 3 O 4 /COF-TpBD) as adsorbents was established for simultaneous determination of aflatoxins, ochratoxins and enniatins in maize before high-performance chromatography tandem spectrometry detection. Fe 3 O 4 /COF-TpBD was facilely fabricated, characterized, and applied for simultaneous extraction of ten mycotoxins from maize. Key parameters affecting MSPE efficiency were investigated. The method possessed good linearity (0.05–50 μg/kg), high sensitivity (0.02–1.67 µg/kg for limits of detection), and satisfactory recoveries (73.8–105.3 %), with relative standard deviations less than 8.5 %. The amount of adsorbent used (5 mg) and the time required (0.5 min each for adsorption and for desorption) for MSPE were greatly shortened in comparison with the previous reports. Therefore, the fabricated Fe 3 O 4 /COF-TpBD exhibited a great potential for rapid extraction of common mycotoxins in maize, which can be attributed to its multiple interactions with the target mycotoxins. [ABSTRACT FROM AUTHOR]

We fabricate Si-based blocked impurity band (BIB) terahertz detectors using p-dopant through a standard silicon device fabrication technology. Comparison of photoresponse of the detectors under alternate operating mode and conventional operation mode (COM) is made. We demonstrate that the detectors can achieve high responsivity through positive bias on the active layer side, namely, alternate operating mode (AOM). The response of the detectors terminates at wavelength of 35~\mu \textm (8.57 THz) under AOM; on the contrary, the response is cutoff at 31~\mu \textm (9.68 THz) with a positive bias on the blocking layer, namely, COM. The relative responsivity at 0.6 V under AOM is 2.3 times of that under COM. By developing an energy band model, we find that the response difference under the two modes originates from the change of band offsets. The electric field in the blocking layer under AOM is much smaller than COM and most of the voltage drops in the active layer under AOM, which leads to the bigger multiplication of the photon-generated carriers than COM. By analyzing the origination of the dark current under the AOM, a method to improve the performance of BIB detectors under AOM is proposed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Two distinctive clusters constrained by H-bond were determined by linear extension method. • The transformation from dimer to H-bond cluster till monomer was concentration-determined. • Different model were proposed for different volume fraction of the mixture. • Vibrational coupling induced splitting theory can reproduce the noncoincidence effects. The isotropic and anisotropic component Raman spectra and H NMR of N-methylpyrrolidone (NMP)/carbon tetrachloride and NMP/methanol binary mixture at different volume fractions have been collected. The polarization Raman frequencies and frequency differences of C O stretching vibration for NMP/methanol mixture show unique concentration-dependence and abrupt jump feature. It is found that the H-bond between solute and solvent does not destroy the noncoincidence (NCE) phenomenon, but has a significant synergistic effect on the NCE. Two distinctive clusters constrained by H-bond and intermolecular interactions were easily determined by means of linear extension method from abrupt jump curve. The experimental phenomena can be well explained by aggregation-induced splitting theory with the proposed dimer structure and H-bond cluster model. Applying the same methodology the conformation of NMP in water has been determined successfully. The establishment of this method will play an important role in the determination of biomolecule aggregation behavior and supramolecular self-assembly structure. [ABSTRACT FROM AUTHOR]