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Bisphenol A (BPA) is a chemical widely used both in plastics production as a food and beverage container and in thermal papers as a color developer. Dietary consumption is the main route of human exposure to BPA, but dermal absorption through handling different papers might be underestimated or ignored. In this study, BPA in different paper products, including different types of papers, receipts and Chinese currencies, were investigated. BPA was detected in receipts (n = 87) and Chinese currencies (n = 46) with concentrations of 0.17-2.675 × 10(4) μg per g paper and 0.09-288.55 μg per g paper, respectively. Except for parchment papers (n = 3), copy papers (n = 3) and food contact papers (n = 3), BPA was measured in all of the other paper products, with levels of 0.01-6.67 μg per g paper. BPA transferred from thermal papers to common papers increased with the increasing contact pressure. Compared with that in water, the migration speed of BPA was doubled in the synthetic sweat. Washing hands could reduce BPA dermal exposure, and washing hands with lotion was the most efficient way. However, about 19-47% of BPA was still found on hands after different washing methods. Dermal absorption via handling of receipts and papers was estimated to be 36.45 ng per day for the general population and 1.54 × 10(-3) to 248.73 μg per day for a cashier. These values are below the maximum doses recommended by the U.S. Environmental Protection Agency and the European Food Safety Authority. However, due to its uncertain adverse effects on human beings, long-term BPA exposure through dermal absorption should be paid more attention, particularly for some occupational populations.

As an important elemental analysis method, laser-induced breakdown spectroscopy (LIBS) enables the qualitative and quantitative determination of the compositions of geological targets on Mars. In order to analyze the chemical compositions of Martian rocks and soils at Gale crater, the ChemCam team built a LIBS spectral library of 408 geological standards using a ChemCam's ground replica under a simulated Martian atmosphere. However, the lack of spectra data with component labels makes it difficult to establish a composition inversion model for predicting the collected spectra. The Mars Surface Composition Detector (MarSCoDe) carried by China's Mars rover, Zhurong, also employs LIBS technology and has successfully conducted related composition detection work. Therefore, this paper proposes a domain-adaptive fully connected neural network (DAFCN) capable of transferring prior knowledge between ChemCam and SDU-LIBS (a LIBS system developed by Shandong University). The model extracts the features of the source domain and target domain through a three-layer fully connected network and uses a domain adaptation function to reduce the difference in feature distribution between the source domain and target domain. Experimental results show that the proposed method is superior to the traditional method without migration. Further, we tried this method to establish the connection between MarSCoDe and other LIBS devices, and then quantitatively analyzed the spectra collected by MarSCoDe. [ABSTRACT FROM AUTHOR]

Burning of joss paper and incense is still a very common traditional custom in countries with a majority Chinese population. The Hungry Ghost Festival which is celebrated in the 7 month of the Chinese calendar is one of the events where joss paper and incense are burned as offerings. This study investigates the impact of the Ghost Month Festival (open burning event) on air quality by analysis of the chemical composition of particulate matter (PM) and rainwater samples collected during this event, compared with data collected throughout the year, as well as bottom ash samples from burning the original joss paper and incense. The results showed that the change in the chemical composition of the rainwater and PM2.5 (PM ≤ 2.5 μm) atmospheric samples could be correlated directly with burning events during this festival, with many elements increasing between 18% and 60% during August and September compared to the yearly mean concentrations. The order of percentage increase in elemental composition (in rain water and PM2.5) during the Hungry Ghost Festival is as follows: Zn > Ca > K > Mg > Fe > Al > Na ∼ Mn ∼ Ti ∼ V > Cu > As > Ni > Co > Cd > Cr > Pb. The chemical composition of the original source materials (joss paper and incense for combustion) and their associated bottom ash were analysed to explain the impact of burning on air quality.

Avian leukemia is an infectious tumorous disease of chickens caused by subgroup A of the avian leukemia virus (ALV-A), which mainly causes long-term viremia, slow growth, immune suppression, decreased production performance, multi-tissue tumors, and even death. The infection rate of this disease is very high in chicken herds in China, causing huge economic losses to the poultry industry every year. We successfully expressed the specific antigen protein of ALV (P27) through recombinant protein technology and screened a pair of highly sensitive monoclonal antibodies (mAbs) through mouse immunity, cell fusion, and antibody pairing. Based on this pair of antibodies, we established a dual antibody sandwich ELISA and gold nanoparticle immunochromatographic strip (AuNP-ICS) detection method. In addition, the parameters of the dual antibody sandwich ELISA and AuNP-ICS were optimized under different reaction conditions, which resulted in the minimum detection limits of 0.2 ng mL−1 and 1.53 ng ml−1, respectively. Commonly available ELISA and AuNP-ICS products on the market were compared, and we found that our established immune rapid chromatography had higher sensitivity. This established AuNP-ICS had no cross-reactivity with Influenza A (H1N1), Influenza A (H9N2), respiratory syncytial virus (RSV), varicella-zoster virus (VZV), Listeria monocytogenes listeriolysin (LLO), and Staphylococcal enterotoxin SED or SEC. Finally, the established AuNP-ICS was used to analyze 35 egg samples, and the results showed 5 positive samples and 30 negative samples. The AuNP-ICS rapid detection method established by our group had good specificity, high sensitivity, and convenience, and could be applied to the clinical sample detection of ALV-A. [ABSTRACT FROM AUTHOR]

Carbon capture, utilization and storage (CCUS) have been projected by the power and industrial sectors to play a vital role towards net-zero greenhouse gas emissions. In this study, we aim to explore the feasibility of a global chemical industry that fully relies on CO2 as its carbon source in 2050. We project the global annual CO2 demand as chemical feedstock to be 2.2–3.1 gigatonnes (Gt), well within the possible range of supply (5.2–13.9 Gt) from the power, cement, steel, and kraft pulp sectors. Hence, feedstock availability is not a constraint factor for the transition towards a fully CO2-based chemical industry on the global basis, with the exception of few regions that could face local supply shortages, such as the Middle East. We further conduct life cycle assessment to examine the environmental benefits on climate change and the trade-offs of particulate matter-related health impacts induced by carbon capture. We conclude that CO2 captured from solid biomass-fired power plants and kraft pulp mills in Europe would have the least environmental and health impacts, and that India and China should prioritize low-impact regional electricity supply before a large-scale deployment of CCUS. Finally, two bottom-up case studies of China and the Middle East illustrate how the total regional environmental and health impacts from carbon capture can be minimized by optimizing its supply sources and transport, requiring cross-sectoral cooperation and early planning of infrastructure. Overall, capture and utilization of unabatable industrial waste CO2 as chemical feedstock can be a feasible way for the net-zero transition of the industry, while concerted efforts are yet needed to build up the carbon-capture-and-utilization value chain around the world. [ABSTRACT FROM AUTHOR]

Acephate is an organophosphorus pesticide (OP) that is widely used to control insects in agricultural fields such as in vegetables and fruits. Toxic OPs can enter human and animal bodies and eventually lead to chronic or acute poisoning. However, traditional enzyme inhibition and colorimetric methods for OPs detection usually require complicated detection procedures and prolonged time and have low detection sensitivity. High-sensitivity monitoring of trace levels of acephate residues is of great significance to food safety and human health. Here, we developed a simple method for ultrasensitive quantitative detection of acephate based on the carbon quantum dot (CQD)-mediated fluorescence inner filter effect (IFE). In this method, the fluorescence from CQDs at 460 nm is quenched by 2,3-diaminophenazine (DAP) and the resulting fluorescence from DAP at 558 nm is through an IFE mechanism between CQDs and DAP, producing ratiometric responses. The ratiometric signal I558/I460 was found to exhibit a linear relationship with the concentration of acephate. The detection limit of this method was 0.052 ppb, which is far lower than the standards for acephate from China and EU in food safety administration. The ratiometric fluorescence sensor was further validated by testing spiked samples of tap water and pear, indicating its great potential for sensitive detection of trace OPs in complex matrixes of real samples. [ABSTRACT FROM AUTHOR]

Bioplastic bags mixed with food waste seem inevitable with the growth of waste classification and the banning of non-biodegradable polymers in China. To solve the asynchronous degradation of both food waste (FW) and bioplastics in the anaerobic digestion process, we investigated to determine the most effective pretreatment method. Among the three treatment options—physical, chemical, and biological—we found that biological pretreatment holds the most promise, primarily due to the efficient catalytic hydrolysis capacity of enzymes. We utilized three types of enzymes—amylases, lipases, and proteinase K—at a concentration of 0.075 g L−1 for pretreatment. The pretreatment process involved subjecting the FW/bioplastics mixture to enzymatic action for a duration of 48 h, at temperatures of 35 °C and 55 °C. We observed that the methane production from anaerobic digestion increased by 22.72%, 32.51%, and 60.95%, respectively, at the temperature of 55 °C when treated with the mentioned enzymes. Additionally, the degradation time of the bioplastic bags decreased from 30 to 24 days. Scanning electron microscopy (SEM) analysis revealed noticeable physical degradation, with the emergence of holes on the surface of the bioplastic following the enzymatic pretreatments and the effect of proteinase K was the most obvious. Further analysis using Fourier-transform infrared spectroscopy (FTIR) indicated that the peak observed at 1700 cm−1 is a characteristic peak of proteinase K depolymerization and the peak sign was significantly weakened after the experiment. This discovery suggests that proteinase K possesses a unique ability to break certain chemical bonds within bioplastics. Furthermore, novel bacterial species were identified in the substrate microbiome after proteinase K pretreatment. Notably, temperature was also a significant factor influencing material degradation. The enzymatic pretreatment enhanced biodegradation, resulting in enhanced methane yield during anaerobic digestion. These findings demonstrated the efficacy of biological pretreatment in effectively addressing the asynchronous degradation issue between food waste and bioplastics. [ABSTRACT FROM AUTHOR]

Studying the influence of oxygen on the growth and properties of diamond has research significance. In this paper, we created an oxygen-rich environment by adding Ni2O3 to the Fe–Ni–C system. Large single crystals of oxygen-containing diamond were successfully synthesized using the temperature gradient method (TGM) in a China-type large volume cubic high-pressure apparatus (CHPA) at 5.5–6.0 GPa and 1360–1600 °C. The results show that with the increase of the Ni2O3 content in the Fe–Ni–C system, the rate of diamond growth decreased while the conditions for diamond growth were enhanced. The morphology of the diamonds changed from {111}, {110} and {113} mixed faces to {111} dominant face. The IR results show that the presence of Ni2O3 increased the nitrogen content in diamonds from 237 ppm to 543 ppm. When 3.5 wt% Ni2O3 was added, A-centre nitrogen began to appear in the diamonds. The XPS results confirmed that oxygen successfully entered the diamond lattice in the form of C–O, C＝O, O–C＝O and N–O with a high concentration of Ni2O3 additives. Meanwhile, there were no obvious impurity inclusions and cracks in the diamond crystals. In addition, the Raman peak position of the diamond appeared to red shift, and the FWHM increased from 4.93 cm−1 to 5.52 cm−1. [ABSTRACT FROM AUTHOR]

In the environment, chromium usually exists in both the trivalent and hexavalent states. Cr(VI) is of particular concern because it is highly toxic. However, it remains challenging to conduct field detection for trace concentrations of different valence states of Cr. Here, we propose a method based on laser-induced breakdown spectroscopy (LIBS) combined with an ion enrichment chip (IEC) to rapidly and sensitively detect the total Cr and Cr(VI) in water and soil. This method was termed IEC–LIBS. A chip with a millimetric channel was used for separating and enriching total Cr and Cr(VI) and LIBS was used for detection. The limits of detection (LoDs) of total Cr and Cr(VI) in water were 10 μg L−1 and 4 μg L−1, respectively, and the recoveries from spiked pool water ranged from 90 to 114%. The method also had good quantitative ability for soil detection, with total Cr and Cr(VI) LoDs of 13.6 mg kg−1 and 3.8 mg kg−1, respectively. The detection sensitivity of this method met the Cr environmental quality standards in China, and the detection time was within 20 min. IEC–LIBS is a simple and environmentally friendly method for detecting trace Cr in different valence states, and it is expected to be useful for field application. [ABSTRACT FROM AUTHOR]

Rapid and stable analysis of coal quality for fine management of coal is essential for the clean and efficient utilization of coal in thermal power plants. In this work, a software-controlled coal analyzer with laser-induced breakdown spectroscopy (LIBS) coupled with X-ray fluorescence spectroscopy (XRF) was developed, which includes an LIBS analysis module, XRF analysis module, sample feeding module, control module and operating software. The instrument not only plays to the strengths of LIBS in multi-element analysis, but also inherits the advantages of XRF in high stability analysis, so that it can be used in power plants for rapid and continuous quality analysis of coal tablets. Based on chemometric regression methods using principal component analysis (PCA) and partial least squares regression (PLS), as well as the spectra of hundreds of coal samples, quantitative prediction models were established, and the industrial test and performance evaluation of the instrument were completed in the Shanxi Yangguang Power Plant in China. The experimental results showed that the R2 of the prediction models for calorific value, ash, volatiles and sulfur were 0.973, 0.986, 0.977 and 0.979, respectively, the RMSEs were 0.26 MJ kg−1, 0.68%, 0.33% and 0.13%, respectively, the RMSEPs were 0.62 MJ kg−1, 1.46%, 0.23% and 0.19%, respectively, and the average SDs were 0.11 MJ kg−1, 0.49%, 0.15% and 0.09%, respectively. The models showed good accuracy and stability, and the repeatability of the measurements of coal quality all met the requirements of national standards, and thus, could meet the needs of power plants. This work provides a new idea for the increasingly mature application of LIBS in coal analysis in various industrial sites. [ABSTRACT FROM AUTHOR]

Single-atom catalysis is a new field that has developed rapidly in recent years and has greatly helped the development of catalytic science. We have processed a large amount of literature data through the Web of Science database. The bibliometric method was used to analyze the development trend and research hotspots over the past 10 years since the concept of single-atom catalysis was proposed in 2011. Results show that the field of single-atom catalysis is currently at a high-speed development stage. China is in a leading position in terms of comprehensive strength, with the largest number of publications and great influence. Most productive journals and institutions are ACS Catalysis and Chinese Acad. Sci. Single-atom catalysis has the most research results in the field of chemistry. In addition, the most commonly used keywords are "density functional theory", "oxygen reduction reaction", "electrocatalysis", "co oxidation", "graphene", "heterogeneous catalysis", "platinum", "hydrogen evolution reaction", which reflect the research direction of the current field. This article reviews the main research content of single-atom catalysts in order to facilitate researchers understanding the current situation in the field, and to also provide some guidance for future research. [ABSTRACT FROM AUTHOR]

The Bi2MoO6 nanosheets are loaded on to γ-Bi2O3 tetrahedron surfaces to form Bi2MoO6/γ-Bi2O3 heterojunctions using a simple calcination method. The photocatalytic degradation efficiencies of the lomefloxacin and the Rhodamine B using the optimum sample are 96% and 99%, respectively, much higher than that of pure phase samples. When the waters from different regions in China were used as solvents, the removal efficiencies of the lomefloxacin and the Rhodamine B are still higher than 88% and 90%, respectively, which shows excellent prospects for practical applications. The photocatalytic degradation efficiencies of these two pollutants are higher than 91% and 95% in the five cycling tests, and the crystal structure of the sample is not changed after cycling. Based on the first-principles calculation, Bi2MoO6 and γ-Bi2O3 form a Z-type energy band structure which accelerates the separation of the photogenerated charge carriers. The Bi2MoO6 valence band potential of 3.25 V and the γ-Bi2O3 conduction band potential of −0.21 V are reserved to generate ˙OH− and O2−, respectively, for the photocatalytic reaction. The degradation of the lomefloxacin is ascribed to the shedding of functional groups and bond breaking with the final products being CO2, F−, H2O, and NO3−. This research shows that Bi2MoO6/γ-Bi2O3 heterojunctions can be employed to purify domestic and textile industrial sewage. [ABSTRACT FROM AUTHOR]

In this study, a high-speed emulsifier and electric dehydrator were used to study the main factors affecting the emulsifying stability of flowback fluids from acidizing oil wells in the DaQing oilfield of China. According to the variation laws of the chemical composition of the transition layer before and after the acid cleaning and descaling treatment, the effects of various components, including inorganic salts, solid nanoparticles, polymers, and surfactants, on the stability of emulsions were investigated. The results showed that sodium chloride (NaCl) had the best ability to maintain the stability of the emulsion. The effect of ferrous sulfide (FeS) nanoparticles on the emulsifying stability of the emulsion was higher than that of silica nanoparticles and calcium carbonate (CaCO3) nanoparticles. The effect of the polymer on the stability of the emulsion was higher than that of the surfactant. When the mass fraction of asphaltene is higher than 0.67%, the stability of the emulsion would increase, creating a difficulty in demulsification. The mechanism of multi-factor synergistic emulsification is clarified in this study. The charges of NaCl itself were packed densely on the interface between oil and water to stabilize the number of charges on the interface, leading to the enhancement of the stability of the interfacial film. FeS nanoparticles, silica (SiO2) nanoparticles, and CaCO3 nanoparticles coalesced on the interface between oil and water to form a dense wrapping layer, which could effectively prevent flocculation, coalescence, or merger of the dispersed phase droplets caused by factors such as electrostatic attraction and interfacial energy changing the spatial structure. These results are of great significance to the efficient treatment of oilfield-produced fluids and environmental protection. [ABSTRACT FROM AUTHOR]

Optofluidics is broadly defined as the fusion of optics and microfluidics. The term optofluidics was coined less than a decade ago. Yet, the term and the concept it encapsulates have pervaded through a significant fraction of the miniature system research community. Optofluidic research continues to grow in unanticipated directions. The Second International Conference on Optofluidics (Optofluidics-2012) showcased some of these developments. The conference was first organized by Xi'an Jiaotong University in 2011 and then Suzhou University, Institute of Nanotechnology, Xi’an Jiaotong University and Suzhou Industrial Park where it was proudly hosted as a summit conference of the CHInano conference in Suzhou on 13–15 Sep 2012. We are happy that Lab on a Chip, a major publication venue for optofluidic research has scheduled this themed issue. [ABSTRACT FROM AUTHOR]

The faience in China suddenly appeared in the Western Zhou Dynasty (1046-771 BC), and its production is considered to be influenced by the West. In this paper, the microstructure and chemical compositions obtained by synchrotron radiation micro-computed tomography (SR-μCT) and μ-probe energy dispersion X-ray fluorescence spectrometry (EDXRF) were combined to disclose the manufacturing information of faience beads excavated from Peng State cemetery in Hengshui, Shanxi Province, China, dated to the Western Zhou Dynasty (1046-771 BC). Based on inner structural features obtained by SR-µCT, it was found that these faience beads could be divided into two types: glazed faience and glassy faience. According to the structural information revealed by the CT slices, it is inferred that these beads were first formed on an organic cylinder and then glazed using the direct application method. The possible sources of copper colorant are copper ores. In addition, the glaze chemical compositions are distinct from Na2O°CaO-SiO2 glaze or glass in the West, and thus, Western Zhou faience should have an indigenous origin in China. Furthermore, the manufacturing features are consistent with the techniques of proto-porcelain during the same time period, but the glaze recipe is distinct from that of proto-porcelain and early glass in China. Consequently, it is proposed that faience in the Western Zhou Dynasty was not the precursor of early glass in China. [ABSTRACT FROM AUTHOR]

Nitrogen (N) content is a significant indicator for evaluating eutrophication. However, the conventional methods, such as alkaline potassium persulfate digestion ultraviolet (UV) spectrophotometry and the Kjeldahl method, always require chemical reagents especially acid or alkaline solution for sample pretreatment. Laser-induced breakdown spectroscopy (LIBS), as an all element analysis technology, is also applied to the detection of N. However, the detection sensitivity for N is poor by conventional atomic LIBS. Therefore, we proposed molecular LIBS to determine N in water. The results showed that the detection sensitivity could be improved by about three orders of magnitude using molecular LIBS compared to atomic LIBS. Optimal limits of detection (LoDs) of 0.6 μg mL−1 in argon (Ar) gas and 1.5 μg mL−1 in helium (He) gas were obtained, respectively. The optimal limits of quantification (LoQs) were 1.98 μg mL−1 and 4.95 μg mL−1 in Ar gas and He gas, respectively. The results indicated that the LoQ of 1.98 μg mL−1 in Ar gas met the surface water environmental quality standards of China (2 μg mL−1 for N). Furthermore, real waters including tap water and river water were analyzed by molecular LIBS. Compared with UV spectrophotometry, the average standard deviation was 8.16%. The work demonstrated the feasibility of molecular LIBS to realize the reliable determination of N in water eutrophication. Molecular LIBS is a promising in situ method for the detection of N in solution. [ABSTRACT FROM AUTHOR]

Chinese liquors are often a very important part of social event in China. Driven by high profit, some illegal traders often use inferior liquors instead of the products with high quality to cheat the customer. Therefore, it is highly required to authenticate Chinese liquors. In this paper a novel method based on ambient glow discharge ionization mass spectrometry has been developed to differentiate Chinese liquors. Volatile components from liquor samples were ionized by the plasma generated by glow discharge and then detected by a commercial linear ion trap mass spectrometer. Consequently, the fingerprint mass spectra of several Chinese liquors were obtained. Combined with principal component analysis, this new method was successfully applied to differentiate different brands of Chinese liquors without any sample pretreatment. Compared with conventional methods, this novel method has the advantages of easy operation, high speed, and high efficiency, which make it a potential tool in the fields of food safety, atmosphere chemistry. [ABSTRACT FROM AUTHOR]

The toxicity of lead (Pb) in water is known to affect cellular components, enzymatic machinery and genomic instability. The detection of lead in water is of great significance. In this study, a method called resonant surface-enhanced LIBS (R-SENLIBS) was proposed to improve the LoD of lead in aqueous solutions. RLIBS was coupled with SENLIBS in this method. Lead in aqueous solutions was compounded in a concentration range of 0.01 to 0.6 mg L−1. The calibration curve of these solutions was built. The value of coefficients of determination (R2) was as high as 0.996 and an LoD of 0.0021 mg L−1 was achieved for the linear calibration range of 0.01 to 0.2 mg L−1. Compared to previously published studies involving lead detection by LIBS, the analysis capability of R-SENLIBS proposed in this study is superior to that of those approaches in these studies. Moreover, the calibration range and LoD in this study meet the drinking water sanitation standard of China (0.01 mg L−1 for Pb, GB5749-2006) and WHO guidelines on lead. Trueness evaluation was carried out by spike and recovery experiments in a real sample of tap water, resulting in recovery values in the range of 101–110%. Spectral comparison indicated that impurities in the substrate and real aqueous solution had little influence on the lead signal in R-SENLIBS. The enhancement mechanism of R-SNELIBS was discussed. The on-resonance excitation and stratified structure of the sample are the two main reasons that lead to a valid signal of Pb. In summary, the method proposed in this study can be an alternative for lead analysis in drinking-water monitoring. [ABSTRACT FROM AUTHOR]

Lime is the most important basic material in ancient architecture. Obtaining lime for construction through calcination is one of the most important inventions of humankind. The raw material of calcined lime is mainly natural limestone and shells. For example, in China's eastern coastal areas that lack limestone resources, "lime" made from oyster shells has been widely used. To understand the history and technological development of ancient architecture, it is of great significance to analyze whether lime in the mortar has been artificially fired and the raw material is limestone or oyster shells. This research proposes an analytical method using infrared spectroscopy, X-ray fluorescence spectroscopy and mercury intrusion microporous detection to determine whether building lime has been calcined and its raw materials. This method has been applied for analyzing and detecting eight lime samples from different ancient ruins. [ABSTRACT FROM AUTHOR]

Silicon carbide (SiC) is a substance found in natural diamond inclusions. Analyzing the influence of SiC doping on the properties of synthetic diamonds is vital to understanding the growth mechanism of natural diamonds and the material composition of the mantle. In this work, China-type large volume cubic high-pressure apparatus (CHPA) (SPD-6 × 1200) was used to simulate the high-temperature and high-pressure environment of diamond growth. The influence of different SiC doping contents on the crystal characteristics of a Ib-type diamond synthesized in a Fe–Ni–C system was investigated at a pressure of 5.8 GPa and a temperature range of 1650–1670 K. Optical microscopy (OM), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy (Raman), X-ray photoelectron spectroscopy (XPS), and photoluminescence spectroscopy (PL) were used to characterize the synthesized crystals. The OM results show that the growth rate of the diamond decreases gradually, and the color changes from yellow to light yellow with an increase in the doping concentration. The FTIR results indicate that the nitrogen element in the crystal mainly appears in the diamond crystal in monatomic form (C center). The nitrogen content in the diamond gradually decreases from 275 ppm to 115 ppm with an increase in the SiC dopant ratio. The Raman data show that the FWHM (full width at half maximum) of the diamond crystal increases with an increase in the doping ratio. The XPS results demonstrate that silicon has successfully entered the diamond lattice with a Si–C bond in the crystal. The PL results indicate that the peak intensity of the nitrogen-vacancy (NV−) color center (638 nm) in the synthesized diamond crystal increases as the doping ratio increases. As the SiC doping content increases, the peak of the NV0 color center (575 nm) appears, and the peak intensity increases. [ABSTRACT FROM AUTHOR]

Due to their relatively high Hf contents (i.e., several hundreds to thousands of ppm), columbite-group minerals (CGMs) are suitable for Lu–Hf isotope analysis, which can provide new insights into the source of such minerals in combination with the U–Pb age of rare-metal deposits. However, few studies have reported Lu–Hf isotope data for CGMs. Tantalum is a major element in CGMs (12–48 wt% Ta2O5) and has a significant effect on measurements of Hf isotopes using MC-ICP-MS. This effect was first evaluated in this study by analysis of mixed Hf–Ta standard solutions with different Ta/Hf ratios and LA-MC-ICP-MS analysis of various CGMs. This analytical artifact reflects serious tailing of the large 181Ta signal onto the 180Hf and 179Hf masses during analysis. Therefore, in order to obtain accurate Hf isotope data for CGMs by MC-ICP-MS, we present an improved chemical separation procedure for Hf from Ta, and also a novel analytical protocol for LA-MC-ICP-MS analysis of CGMs. Accurate in situ176Hf/177Hf ratios for CGMs can be obtained by normalization to 178Hf/177Hf = 1.4672, rather than 179Hf/177Hf = 0.7325, using the exponential law. This approach was validated by solution and laser ablation MC-ICP-MS analysis of four CGM samples from China and Africa. The Lu–Hf isotopic composition of CGMs provides a new geochemical tracer for rare-metal deposits. [ABSTRACT FROM AUTHOR]

Zenghou Yi Tomb (433 BC) in the early Warring States Period of China is a very important archaeological discovery. Lots of lacquerware was unearthed here, typically representative of that from Chu in the Warring States Period. This article presents analyses of the lacquered inner coffin and a lacquered zither from the tomb, and their surface is red lacquer, supplemented by additional black and yellow patterns. Yellow painted lacquerware remains relatively rare from this period and therefore deserves further study. Numerous methods including three-dimensional (3D) video microscopy and scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS), pyrolysis-gas chromatography/mass spectroscopy (Py-GC/MS), Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy as well as enzyme-linked immunoassay (ELISA) were adopted to analyze the lacquer and pigments from the two artifacts. The results of this study reveal that lacquer samples from both the two artifacts have multilayered structures and contained added eggs and oil. The red pigment on the lacquer surface was made of cinnabar mixed with lacquer, the black one was carbon black mixed with lacquer, while the yellow one was pararealgar mixed with gelatin. These differences may explain the relative rarity of yellow painted lacquerware from early periods. [ABSTRACT FROM AUTHOR]

In order to clarify the research status, hot spots and development trend in the field of conversion of carbon dioxide, a large amount of literature data set in the scientific network database was analyzed by bibliometrics. Through the statistical analysis of the publication data, it is observed that China's publishing industry has entered a rapid development stage: the comprehensive strength ranks the first in the world, the volume of publications is the largest, and the influence is also greater. The most productive journal and institution are Applied Catalysis B-Environmental and Chinese Academy of Sciences. In addition, the research status and problems of the photocatalytic conversion of carbon dioxide are briefly introduced. Finally, according to the analysis results and the existing problems, the future development of photocatalytic CO2 conversion is underway. [ABSTRACT FROM AUTHOR]

In this study, a gold immunochromatographic assay (GICA) based on a penicillin receptor protein (PBP) is proposed to simultaneously detect penicillin, cephalosporin, and carbapenem antibiotics in milk and chicken. A mutant PBP, carboxy-terminal of the β-lactam sensor-transducer protein (BlaR-CTD, I188KS19CG24C) from Bacillus licheniformis ATCC14580 was expressed in E. coli as a soluble His-tag fusion protein. The purified BlaR-CTD mutant was labeled with colloidal gold (CG-BlaR-CTD-M) and applied to develop GICA. The GICA method was performed based on a competitive form, where the binding of the ampicillin-bovine serum albumin conjugate (Amp-BSA) to CG-BlaR-CTD-M was inhibited by free β-lactams in samples. The performance of the assay was confirmed by analysis of milk and chicken samples. The limits of detection of 21 β-lactam antibiotics met the maximum residue limits set by the European Union and China. The GICA gave results within 10 min, thus providing a rapid and reliable method for the on-site detection of multiple β-lactams in milk and chicken samples. [ABSTRACT FROM AUTHOR]

Herein, the characteristics of heavy FeS-doped diamond crystals were studied using a China-type large volume cubic high-pressure apparatus (CHPA) with FeNi alloy as the catalyst at 6.0–6.5 GPa and 1350–1400 °C. The crystals were characterized via optical microscopy (OM), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR) and Raman spectroscopy (Raman). OM of the crystal showed that the crystals cracked when the doping ratio was increased, and an increase in pressure was beneficial to alleviate the phenomenon of cracking. The XPS spectrum of the crystal showed that S successfully enters the diamond lattice in three bonding modes, C–SO2–C6H5, C–S–SO2–C and C–S, under high concentration doping conditions. The infrared spectrum showed that the content of N in the crystal decreased with an increase in the doping ratio. The Raman spectroscopy analysis showed that the heavy FeS-doped Ib-type diamond single crystal has a high quality sp3 structure, and the full width at half maximum (FWHM) of the crystal gradually broadened as the doping ratio increased. Additionally, it showed that increasing the pressure under the same doping concentration is beneficial to increase the crystallinity of the crystal. [ABSTRACT FROM AUTHOR]

Heavy metal particles in water are mainly derived from acidic industrial wastewater and seriously endanger the environment and public health. In this work, the pH effect on the detection of toxic metals in wastewater by laser-induced breakdown spectroscopy coupled with a phase transformation method (LIBS-PT) was investigated. Heavy metals of cadmium (Cd) and chromium (Cr) were selected as examples. The results showed that the presence of acids in wastewater inhibited the spectral enhancement of LIBS-PT on a metal substrate. This was mainly due to the presence of the salt floccule formed by the reaction of an acid with a metal substrate on the substrate surface. The floccule content increased as pH decreased, and the corresponding substrate ablation threshold increased. Therefore, more laser energy was used for ablation, resulting in reduced laser energy for ionization and reduced electron density. Eventually, spectral intensity decreased as electron density decreased. However, there was no significant change in plasma temperature. Meanwhile, the determination coefficients (R2) of Cd and Cr were all above 0.99 under the optimal pH 6.5 and on the optimal zinc (Zn) substrate. Limits of detection (LoDs) of 0.0089 mg L−1 and 0.0006 mg L−1 for Cd and Cr were obtained, respectively. The LoDs of Cd and Cr elements met the sewage discharge standard of China. The results indicated that the detection sensitivity of heavy metal elements in acidic wastewater can be significantly improved by optimizing the pH value of the solution using LIBS-PT. [ABSTRACT FROM AUTHOR]

Textile dyeing industries using conventional small molecular weight organic dyes generate large quantities of refractory wastewater every day, which causes serious problems to the environment. Here, a promising clean method for textile colouration without using organic dyes is reported, which consists of two parts: 1, a darkness control system based on immobilizing functionalized carbon black nanoparticles onto cotton fabric via radiation-initiated co-graft polymerization with vinyl monomers; 2, an approximate RGB (red, green and blue) colour control system by immobilizing cobalt blue, cobalt green, iron oxide red nanoparticles onto cotton fabric that can colourate the cotton fabric with not only the three primary RGB colours but also a series of different colours by blending the three-primary RGB colours. The colour of the cotton fabric can be controlled precisely by changing the degree of grafting of the nanoparticles. The strong covalent bonds network between the nanoparticles and the cotton fabric prevents the release of nanoparticles during usage and the colour remains intact even after intense laundering, equivalent to 100 domestic laundering cycles. The wastewater when using this novel dyeing method is significantly cleaner than the real dyeing industry wastewater and can be discharged without further treatment, taking into consideration directives defined by China and other major textile-producing countries. [ABSTRACT FROM AUTHOR]

In this work, neutron diffraction (ND) and neutron resonance transmission imaging (NRTI) are applied for the material characterization of composite artefacts, two bimetallic sword fragments from ancient China, in order to highlight the presence and distribution of phases and elements in the objects. The investigation was carried out at the INES beamline, a time-of-flight powder diffractometer operating at the ISIS neutron and muon source in the UK. ND was applied to identify and quantify crystalline phases, while NRTI, by means of a position sensitive n-GEM based neutron detector, provided us with the distribution of different elements in the objects. NRTI demonstrates the possibility of enhancing several elements (e.g. Fe, Cu, Ag, Sn, Sb, As, Co, Cr, In, and Mn) in neutron transmission images, achieving a spatial resolution of about 1.6 mm. Elemental mapping was performed by selecting some of the most intense neutron resonances (up to several keV) in the absorption spectra. [ABSTRACT FROM AUTHOR]

A selective and robust UPLC-MS/MS method has been firstly developed for simultaneous determination of three anti-tumor tyrosine kinase inhibitors (anlotinib, ANL; ceritinib, CER; ibrutinib, IBR) in rat plasma using cost-effective protein precipitation extraction. LC separation was achieved on Waters XBrige C18 column (50 mm × 2.1 mm, 3.5 μm) under gradient conditions in a run time of 5 min. ESI+ was involved through mass spectrometry. Multiple reaction monitoring transitions were at m/z 408.2 → 339.2 for ANL, 558.2 → 433.2 for CER, 441.0 → 138.0 for IBR, 285.0 → 193.1 for diazepam (internal standard), respectively. The optimized method was validated based on US FDA guideline, EMEA guideline as well as Pharmacopoeia of the People's Republic of China. The assay was linear in the range of 0.1–20 ng mL−1 for ANL, 2–1000 ng mL−1 for CER, 1–500 ng mL−1 for IBR. Intra- and inter-day accuracy and precision for all analytes were ≤13.84% and ≤12.56%, respectively. ANL, CER and IBR were sufficiently stable under most investigated conditions. The optimized method was successfully applied for a pharmacokinetic study after single oral gavage administration of mixture (ANL, CER and IBR) at dose of 6 mg kg−1, 25 mg kg−1 and 10 mg kg−1. [ABSTRACT FROM AUTHOR]

In typical photoelectrochemical (PEC) biosensing assays, electrodes are generally modified with photoactive probes and/or target recognition probes, which makes the processes complicated, time-consuming, and difficult to achieve excellent reproducibility. Hence, to overcome such shortcomings, we propose here an immobilization-free and label-free PEC aptasensor using solution-phase methylene blue (MB) as the PEC signal probe. Based on the unique T–Hg2+–T base pairs, and the diffusivity difference between free MB molecules and the MB/G-quadruplex composite towards the ITO electrode surface with negative charge, the “signal-off” approach for Hg2+ detection is developed. In the presence of target Hg2+, via the T–Hg2+–T bond formation, the two sticky ends of the hairpin DNA probe form a rigid duplex stem, which triggers the exonuclease III-facilitated target cycling amplification, and the formation of multiple G-quadruplexes. Upon the intercalation of MB in G-quadruplexes, significantly decreased photocurrent is obtained owing to the increased electrostatic repulsion between the MB/G-quadruplex composite and the ITO electrode. Therefore, highly sensitive and ultrasensitive Hg2+ determination is achieved, with a low detection limit of 1.2 pM, well below the maximum allowable Hg2+ level in drinking water defined by the WHO, China's Ministry of Health, and the US EPA. Due to the avoidance of sophisticated electrode modification and recognition probe immobilization processes, as well as an expensive labeling procedure, the PEC aptasensor proposed here demonstrates the advantages of simplicity, good reproducibility, rapidness and low cost. [ABSTRACT FROM AUTHOR]

Highly efficient macroalgae based chemical factories and environmental protection have been comprehensively studied for the first time to displace fossil resources to mitigate climate change impact. Wild macroalgae by (bio)phytoremediation and residual macroalgae by biosorption can be used to treat wastewaters, marine environment, soil and sludge. Cultured macroalgae can be processed through drying, milling, grinding, suspension in deionised water and filtration extracting sap of heavy metals; centrifugation of solids recovering nutrients; ion exchange resins of supernatants separating protein and polysaccharides; dialysis purifying protein from salts and pretreatment of polysaccharides producing a sugar platform. Protein profiling shows the presence of the essential amino acids as well as others as food additive, flavour enhancer and pharmaceutical ingredient. Sugars can be converted into a chemical: levulinic acid by controlled acid hydrolysis; 2,5-furandicarboxylic acid by heterogeneous catalytic reaction; succinic acid by tricarboxylic acid cycle; lactic acid by fermentation, with 3–5 times market value than bioethanol. Protein, sugar based chemical and inorganics give the highest to the lowest climate change impact savings of 12, 3 and 1 kg CO2 equivalent per kg product. Their cost of production is estimated at $2010 t−1, significantly lower than their market prices, making the integrated marine biorefinery system economically more attractive than lignocellulosic terrestrial biorefinery systems. Social life cycle assessment indicates that the highest to the lowest avoided social impacts will be from the displacements of animal based protein, sugars and minerals, in Indonesia, China and Philippines (producing 27 million tonnes per annum, 93% of global production). [ABSTRACT FROM AUTHOR]

Solar energy-driven seawater desalination is a low-cost energy-based method to address the problem of global water shortage. Herein, a high efficiency solar-driven steam generation device is designed by in situ hydrothermal deposition of MoS2 nanosheets on glass fabric (GF). MoS2 nanosheets are homogeneously distributed on flexible fabric and the thickness is about 0.9-1 mm, constructing a hierarchical porous microstructure. This leads to efficient evaporation performance, attributed to the strong light absorption ability in the full solar spectrum range of MoS2, multiple reflections inside the pores and water transportation channels of gaps between glass fibers. The net evaporated water mass loss attains 1.31 kg m-2 after 1 h irradiation under one sun with an efficiency of 90.4% which is much higher than that achieved using a blank membrane (27.3%). The potential application of as-fabricated devices for seawater desalination is demonstrated by purifying water from the Yellow Sea, China, and the quality of desalted water meets the standard of the World Health Organization's drinking water requirement. The membrane exhibited an almost complete removal of rhodamine B and tetracycline, endowing the membrane with excellent photocatalytic self-cleaning ability. The flexible and tailorable film with functional design provides a practical and efficient strategy to enhance solar-driven water evaporation performance. [ABSTRACT FROM AUTHOR]

A portable method for on-site detection of three mycotoxins was developed based on a sonic toothbrush, microfluidic chip and smartphone. Our method could complete all procedures, including sample pretreatment, signal conversion and processing, without any sophisticated instruments. The limits of detection for these mycotoxins were lower than the limit values in cereals in the standards of China and the European Union. [ABSTRACT FROM AUTHOR]

Isotopic compositions of antimony (Sb) in airborne particles could reveal the sources and geochemical processes of Sb. Today, the precise analysis of the Sb isotopic ratio in airborne particles is still challenging due to technical difficulties in the sampling and pretreatment processes. In this study, traditional methods of sampling and pretreatment of Sb in airborne particles were optimized to meet the isotope measurement requirements. Suitable digestion methods were suggested for various membrane filters (MF) of different materials and brands, and the Sb blank values in these membrane filters were compared. The results showed that the Whatman brand quartz microfiber MF had the lowest Sb blank value (1.13 ng cm−2), and could meet the needs of continuous large flow sampling, making it the most ideal MF for sampling Sb in airborne particles for the subsequent measurement of Sb isotope ratios. Synthetic samples of the MF spiked with certified reference materials (CRMs) were digested and tested. Nearly identical ε123Sb values were observed among CRMs, (MF + CRMs), and (MF + CRMs) subtracting the content proportion of MF, which indicated that the isotope fractionation occurred during the pretreatment was negligible, and that the Sb isotopic composition of airborne particulate matter was basically not affected by the Whatman brand quartz microfiber MF. This method has been successfully applied to total suspended particles and fine particulate matter (PM2.5) collected in Guiyang in southwest China. [ABSTRACT FROM AUTHOR]

Covering: up to July 2020 Drugs derived from traditional Chinese medicine (TCM) include both single chemical entities and multi-component preparations. Drugs of both types play a significant role in the healthcare system in China, but are not well-known outside China. The research and development process, the molecular mechanisms of action, and the clinical evaluation associated with some exemplificative anticancer drugs based on TCM are discussed, along with their potential of integration in western medicine. [ABSTRACT FROM AUTHOR]

In the field of air analysis, highlights within this review period included: new isotopic data for reference dust materials; a new device for preparing and mounting delicate air filter samples for X-ray analysis and use of oxygen-mediated mass-shift ion chemistry for measuring sulfur in aerosol samples by ICP-MS. The use of DGT and ionic liquids for preconcentrating trace elements and other analytes from waters has become more established. The resurgence of interest in As speciation has been noted with extensive reviews as well as methods for the challenging determination of thioarsenic species. Improvements in methodologies have achieved LODs with GC-MS that were once only possible with ICP-MS, thereby making it possible for a larger number of laboratories to undertake speciation analysis. Field preconcentration methods and hand-held XRF instruments have made it easier to screen contaminated waters, thereby allowing sampling sites to be selected more effectively. There has been renewed interest in atomic emission sources such as the arc, GD and plasmatron for the analysis of plants and soils. The upward trend in publication of LIBS methods continued but many lacked validation through comparison with established methods or analysis of CRMs. There is a clear need for closer collaboration between the physicists driving fundamental developments in plasma spectroscopy and analytical geochemists, who understand the complexities of environmental samples and the requirement to implement robust QC procedures. Interest in multivariate analysis of pXRFS spectra to predict soil properties related to fertility has increased. Much research effort continues to be devoted to characterisation of matrix-matched geological RMs, both synthetic and natural samples, particularly for in situ analysis by microanalytical techniques, such as LA-MC-ICP-MS and SIMS. Such RMs are essential to compensate for matrix effects and need to be available in sufficient quantities to enable interlaboratory comparisons based on the same RM. The increased access to MC-ICP-MS instrumentation, especially in China, is reflected in the diverse range of isotopic systems now being studied. Most studies present incremental improvements to existing separation procedures or measurement protocols. [ABSTRACT FROM AUTHOR]

China has abundant vanadium–titanium magnetite resources. It is important to extract the Fe, Ti and V elements from vanadium–titanium magnetite by recycling. The HIsmelt smelting reduction process is an effective method to smelt vanadium–titanium magnetite. In the present study, the phase composition of the high-titanium slag produced under different temperature and composition conditions under the HIsmelt smelting reduction process was first analyzed via thermodynamic calculations. An experimental scheme was further designed to study the influence of different factors on the crystallization behavior of the high-titanium slag. The thermodynamic calculation results showed that perovskite and pseudobrookite are the main enrichment phases of the high-titanium slag during the slag cooling phase. With the increase in the TiO2 content, the main titanium-rich phase changed from perovskite to pseudobrookite. As the basicity decreased, the main titanium-rich phase that precipitated was pseudobrookite. The experimental results were basically consistent with the thermodynamic results. With the decrease in the TiO2 content, the main titanium-rich phase in the slag evolved from plate-like anosovite to columnar or dendritic perovskite, and the size of the precipitated crystals decreased. When the content of TiO2 decreased to 23%, the precipitate morphology of some perovskite crystals changed from columnar to dendritic. As the basicity of the slag decreased, the titanium-rich phase in the slag changed from perovskite to anosovite. When the basicity of the slag was 0.8, anosovite became the only titanium-rich phase. Anorthite was also formed and had a thin rod shape. In addition, with the decrease in the MgO/Al2O3 ratio, the composition of anosovite changed from (MgTi2O5)0.8·(Al2TiO5)0.2 to (MgTi2O5)0.6·(Al2TiO5)0.4. The research results provide a reference for the further understanding of the crystallization behavior of the high-titanium slag produced by the HIsmelt smelting reduction process and the utilization of the titanium-rich slag as a resource. [ABSTRACT FROM AUTHOR]

Characterization of dendrimers as potential therapeutics or drug carriers is complete only when toxicity is assessed. There are numerous studies on the influence of surface modification of PAMAM and PPI dendrimers on their cytotoxic properties but without proposing a mechanism for their toxic effect. In this study cytotoxicity profiles of acid-terminated PAMAM G3.5 and amino-terminated PAMAM G4 in comparison to unmodified amino-terminated PPI-G4 and maltotriose modified PPI-G4 dendrimers were checked. Also the mechanism of cell death in Chinese hamster ovary (CHO) and human ovarian carcinoma (SKOV3) cell lines was investigated. The anionic PAMAM G3.5 dendrimers seem to be the most suitable dendrimers for therapeutic applications, because of their high biocompatibility and low cytotoxicity. Cationic PPI-G4 and PAMAM G4 were the most harmful for both CHO and SKOV3 cell lines, especially in high doses. Maltotriose modification has significantly reduced toxicity within the series of PPI-G4 dendrimers. The moderately doxorubicin and cisplatin resistant human ovarian carcinoma SKOV3 cell line was more vulnerable to modified PPI dendrimers than Chinese hamster ovary CHO cell line which does not show resistance to majority of anticancer agents. This unique property makes these dendrimers potentially interesting for an anticancer therapy. [ABSTRACT FROM AUTHOR]

Co K-edge XAFS measurements were carried out to characterize the oxidation state and chemical environment of cobalt element in the blue decorations of blue-and-white porcelains manufactured by Jingdezhen official kiln during Yuan and Ming dynasties with the aim to investigate its coloring mechanism. XANES spectra showed that cobalt was present as both divalent and trivalent ions and the ratios of Co2+/Co3+ were almost similar for all samples with different historical periods. EXAFS analysis indicated that cobalt atom was situated in both octahedral and tetrahedral sites. Considering the empirical optical absorption in visible region, it was assumed that divalent ions located at tetrahedral sites made the main contribution to the blue color. [ABSTRACT FROM AUTHOR]

Mercury (Hg) is a toxic metal released into the environment through human activities and natural processes. Human activities have profoundly increased the amount of Hg in the atmosphere and altered its global cycling since the Industrial Revolution. Gaseous elemental Hg is the predominant form of Hg in the atmosphere, which can undergo long-range transport and atmospheric deposition into the aquatic systems. Hg deposition elevates the methylmercury (MeHg) level in fish through bioaccumulation and biomagnification, which poses a serious human health risk. Acute poisoning of MeHg can result in Minamata disease, while low-level long-term exposure in pregnant women can reduce the intelligence quotient of infants. After five sessions of intergovernmental negotiation, the Minamata Convention on mercury entered into force in August 2017 to protect human health and the environment from Hg pollution. Currently China contributes the largest quantity of Hg production, consumption, and emission globally. However, the status of Hg pollution in the environment in China and its associated health risk remains relatively unknown, which hinders the development of implementation plans of the Minamata Convention. In this paper, we provide a comprehensive review on the atmospheric release of Hg, distribution of air Hg concentration, human exposure to MeHg and health impacts caused by Hg pollution in China. Ongoing improvement of air pollution control measures is expected to further decrease anthropogenic Hg emissions in China. Air Hg concentrations in China are higher than the background values in the Northern Hemisphere, with spatial distribution largely influenced by anthropogenic emissions. Long-term observations of GEM in China show a decline in recent years. The net Hg transport outflow from China in 2013 is estimated to be 511 t year -1 , and ∼60% of such outflow is caused by natural surface Hg emissions. Hg concentrations in fish and rice in China are relatively low and therefore the associated risks of human Hg exposure are low. Future research needs and recommendations for the implementation of the Minamata Convention are also discussed in this paper.

A sample delivery system is one of the key parts of serial crystallography. It is the main limiting factor affecting the application of serial crystallography. At present, although a variety of useful sample delivery systems have been developed for serial crystallography, it still remains the focus of the field to further improve the performance and efficiency of sample delivery. In existing sample delivery technologies, samples are usually delivered in linear motion. Here we show that the samples can also be delivered using circular motion, which is a novel motion mode never tested before. In this paper, we report a microfluidic rotating-target sample delivery device, which is characterized by the circular motion of the samples, and verify the performance of the device at a synchrotron radiation facility. The microfluidic rotating-target sample delivery device consists of two parts: a microfluidic sample plate and a motion control system. Sample delivery is realized by rotating the microfluidic sample plate containing in situ grown crystals. This device offers significant advantages, including a very wide adjustable range of delivery speed, low background noise, and low sample consumption. Using the microfluidic rotating-target device, we carried out in situ serial crystallography experiments with lysozyme and proteinase K as model samples at the Shanghai Synchrotron Radiation Facility, and performed structural determination based on the serial crystallographic data. The results showed that the designed device is fully compatible with the synchrotron radiation facility, and the structure determination of proteins is successful using the serial crystallographic data obtained with the device.

Anthropogenic emissions in Asia have significantly increased during the last two decades; as a result, the induced air pollution and its influences on radiative forcing and public health are becoming increasingly prominent. The Aerodyne Aerosol Mass Spectrometer (AMS) has been widely deployed in Asia for real-time characterization of aerosol chemistry. In this paper, we review the AMS measurements in Asia, mainly in China, Korea, Japan, and India since 2001 and summarize the key results and findings. The mass concentrations of non-refractory submicron aerosol species (NR-PM 1 ) showed large spatial distributions with high mass loadings occurring in India and north and northwest China (60.2-81.3 μg m -3 ), whereas much lower values were observed in Korea, Japan, Singapore and regional background sites (7.5-15.1 μg m -3 ). Aerosol composition varied largely in different regions, but was overall dominated by organic aerosols (OA, 32-75%), especially in south and southeast Asia due to the impact of biomass burning. While sulfate and nitrate showed comparable contributions in urban and suburban regions in north China, sulfate dominated inorganic aerosols in south China, Japan and regional background sites. Positive matrix factorization analysis identified multiple OA factors from different sources and processes in different atmospheric environments, e.g., biomass burning OA in south and southeast Asia and agricultural seasons in China, cooking OA in urban areas, and coal combustion in north China. However, secondary OA (SOA) was a ubiquitous and dominant aerosol component in all regions, accounting for 43-78% of OA. The formation of different SOA subtypes associated with photochemical production or aqueous-phase/fog processing was widely investigated. The roles of primary emissions, secondary production, regional transport, and meteorology on severe haze episodes, and different chemical responses of primary and secondary aerosol species to source emission changes and meteorology were also demonstrated. Finally, future prospects of AMS studies on long-term and aircraft measurements, water-soluble OA, the link of OA volatility, oxidation levels, and phase state were discussed.

A bibliometric analysis of published papers with the key words "positive matrix factorization" and "source apportionment" in 'Web of Science', reveals that more than 1000 papers are associated with this research and that approximately 50% of these were produced in Asia. As a receptor-based model, positive matrix factorization (PMF) has been widely used for source apportionment of various environmental pollutants, such as persistent organic pollutants (POPs), heavy metals, volatile organic compounds (VOCs) as well as inorganic cations and anions in the last decade. In this review, based on the papers mainly from 2008 to 2018 that focused on source apportionment of pollutants in different environmental media, we provide a comparison and summary of the source categories of typical environmental pollutants, with a special focus on polycyclic aromatic hydrocarbons (PAHs), apportioned using PMF. Based on the statistical average, coal combustion and vehicular emission, are shown to be the two most common sources of PAHs, and contribute much more to emissions than other sources, such as biomass burning, biogenic sources and waste incineration. Heavy metals were mainly from agricultural activities, industrial and vehicular emissions and mining activities. Quantitative source apportionment on pollutants such as VOCs and particulate matter were also apportioned, showing a prominent contribution from fossil-fuel combustion. We conclude that, aside from natural sources, abatement strategies should be focused on changes in energy structure and industrial activities, especially in China. Source apportionment of typical POPs including polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs), halogenated flame retardants (HFRs) and perfluorinated compounds (PFCs) is less comprehensive and further study is required.

The considerable spatial and temporal variabilities of nitrogen (N) processing introduce large uncertainties for quantifying N cycles on a large scale, particularly in plain river network regions with complicated hydrographic connections and mixed multiple N sources. In this paper, the dual isotopes δ15N and δ18O and dissolved anions in regularly collected samples (n = 10) from the studied river, which is one of the most seriously polluted rivers in the plain river network regions of the Taihu Lake catchment, were analyzed to ascertain the main nitrate (NO3-) sources and watershed N processing in the context of monsoon climate. The seasonal variations in precipitation, temperature, and hydrology play key roles in the regulation of the river NO3- concentration, NO3- sources, and watershed N processing. Nitrification of N-containing materials in the soil was possibly the major source of NO3- all year round, especially in the rainy season, whereas manure and sewage significantly contributed to the NO3- load in the Taige River in the dry season. Nitrification and denitrification processes within the area were closely related. The significant negative relationship between the water temperature and δ18O-NO3- values indicated the occurrence of nitrification in the soil throughout the year. By contrast, seasonal variations of denitrification were apparent from May to July with the high soil temperature and moisture, thereby indicating the occurrence of denitrification (22.9%) within the watershed. After the assessment of temporal variations of NO3- sources and watershed N processing, improved environmental management practices can be implemented to protect water resources and prevent further water quality deterioration in human-impacted watersheds.

The rationale behind this paper was to review the available data regarding the current knowledge on the levels and trends of pharmaceuticals and personal care products (PPCPs) in Taihu Lake. The ecological risk associated with some of the PPCPs was also assessed. 36 PPCPs have been detected in the water, sediment and biota of Taihu Lake. These contaminants primarily emanate from anthropogenic activities in and around the lake. The northern part of the lake is highly polluted as compared to other parts because it receives most effluents from wastewater treatment plants (WWTPs), and domestic and industrial waste discharge from developed cities nearby. Based on the risk quotient (RQ) values, ciprofloxacin, ofloxacin, 17β-estradiol, roxithromycin and tetracycline may present a high ecological risk to organisms living in Taihu Lake. Regular monitoring is required to check the levels of PPCPs as they are regularly released into the lake. Investigations into the joint toxicities of PPCPs to aquatic organisms and the spread of antibiotic-resistant bacteria and genes in Taihu Lake are highly recommended. Special attention in terms of policy and research should be given to the northern part of the lake.

Pteridium aquilinum, Osmunda cinnamomea Linn, and Athyrium multidentatum (Doll.) Ching are three fern species widely consumed as potherbs and traditional medicinal herbs in China. Nevertheless, no detailed comparative assessments of their nutrient values and bioactivities have been reported. In this paper, we examined the nutrient content of these ferns and the bioactivities of their extracts with a comparative method. The results indicated that they were nutrient dense for proteins, carbohydrates, fat and minerals. Compared with Pteridium aquilinum and Osmunda cinnamomea Linn, the extract from Athyrium multidentatum (Doll.) Ching was found to possess the strongest antioxidant activity, protective effects on biomolecules, cellular antioxidant activity, and antiproliferative effects owing to its highest total phenolic (476.52 ± 11.26 mg GAE per g extract) and total flavonoid (924.81 ± 4.25 mg RNE per g extract) contents. Further, Athyrium multidentatum (Doll.) Ching can lead to caspase-3 activation, poly ADP-ribose polymerase cleavage, mitochondrial membrane potential (MMP) reduction and inhibition of wound-healing in a dose-dependent manner in HepG2 cells. These results demonstrate the remarkable potential of Pteridium aquilinum, Osmunda cinnamomea Linn, and Athyrium multidentatum (Doll.) Ching as valuable sources of nutrients and natural antioxidants, and among which Athyrium multidentatum (Doll.) Ching has potential anticancer properties.

In this paper, the effect and mechanism of Salicornia bigelovii Torr. plant salt (SPS) on blood pressure in Sprague Dawley (SD) rats were investigated. The results showed that the edible salt induced hypertension, but the SPS did not. Organ indices and Hematoxylin-Eosin (HE) staining analysis indicated that SPS had a protective effect on the kidney and liver. In comparison with the edible salt-treated group, nitric oxide (NO) content, angiotensin-II (Ang-II) and endothelin-1 (ET-1) levels in the serum of the SPS-treated group had no obvious changes, but serum creatinine concentration significantly decreased. Moreover, superoxide dismutase (SOD) and Na(+)-K(+)-ATPase activity increased while malondialdehyde (MDA) content decreased in the SPS-treated group. In conclusion, a long-term high salt intake could lead to hypertension. SPS, as a salt substitute, could increase the body's antioxidant ability to protect the kidney and liver from the damage caused by a high salt intake and effectively avoid the occurrence of hypertension.

Antibiotics are still widely applied in animal husbandry to prevent diseases and used as feed additives to promote animal growth. This could result in antibiotic resistance to bacteria and antibiotic residues in animals. In this paper, Enterobacteriaceae isolated from four integrated fish farms in Zhongshan, South China were tested for antibiotic resistance, tetracycline resistance genes, sulfonamide resistance genes, and class 1 integrons. The Kirby-Bauer disk diffusion method and polymerase chain reaction (PCR) assays were carried out to test antibiotic susceptibility and resistance genes, respectively. Relatively high antibiotic resistance frequencies were found, especially for ampicillin (80%), tetracycline (52%), and trimethoprim (50%). Out of 203 Enterobacteriaceae isolates, 98.5% were resistant to one or more antibiotics tested. Multiple antibiotic resistance (MAR) was found highest in animal manures with a MAR index of 0.56. Tetracycline resistance genes (tet(A), tet(C)) and sulfonamide resistance genes (sul2) were detected in more than 50% of the isolates. The intI1 gene was found in 170 isolates (83.7%). Both classic and non-classic class 1 integrons were found. Four genes, aadA5, aadA22, dfr2, and dfrA17, were detected. To our knowledge, this is the first report for molecular characterization of antibiotic resistance genes in Enterobacteriaceae isolated from integrated fish farms in China and the first time that gene cassette array dfrA17-aadA5 has been detected in such fish farms. Results of this study indicated that fish farms may be a reservoir of highly diverse and abundant antibiotic resistant genes and gene cassettes. Integrons may play a key role in multiple antibiotic resistances posing potential health risks to the general public and aquaculture.

Regional air quality monitoring networks (RAQMN) are urgently needed in China due to increasing regional air pollution in city clusters, arising from rapid economic development in recent decades. This paper proposes a methodological framework for site location optimization in designing a RAQMN adapting to air quality management practice in China. The framework utilizes synthetic assessment concentrations developed from simulated data from a regional air quality model in order to simplify the optimal process and to reduce costs. On the basis of analyzing various constraints such as cost and budget, terrain conditions, administrative district, population density and spatial coverage, the framework takes the maximum approximate degree as an optimization objective to achieve site location optimization of a RAQMN. An expert judgment approach was incorporated into the framework to help adjust initial optimization results in order to make the network more practical and representative. A case study was used to demonstrate the application of the framework, indicating that it is feasible to conduct site optimization for a RAQMN design in China. The effects of different combinations of primary and secondary pollutants on site location optimization were investigated. It is suggested that the network design considering both primary and secondary pollutants could better represent regional pollution characteristics and more extensively reflect temporal and spatial variations of regional air quality. The work shown in this study can be used as a reference to guide site location optimization of a RAQMN design in China or other regions of the world.

This paper presents the concentrations, vertical profiles and possible sources of selected major and trace elements in a sediment core covering ∼150 years of sedimentation in Lake Chaohu, eastern China. Element concentrations were measured by portable X-ray Fluorescence Spectroscopy (XRF) and were used to evaluate possible environmental consequences of the recent industrialization in China. Statistical analyses identify four groups: (1) organic carbon (OC), total nitrogen (TN), Pb, Zn, and As associated with the use of chemical fertilizers and pesticides; (2) Mn, Cr, Ni and Cu from industrial and mining activities; (3) Fe, Rb, K, Co, Ti and Ca influenced by post-depositional processes and land exploitation; and (4) Zr and Sr from the soil. The vertical profiles of elements placed in the first two groups show distinct increases in concentrations above depths of 20 cm (~1978), coincident with the timing of industrialization in China, and the anthropogenic-derived fluxes are higher than the lithogenic-derived fluxes over the last three decades. With the exception of Zr and Sr, association of the measured metals with organic carbon and nitrogen suggests that organic matter may act as a carrier phase. The geoaccumulation index (I(geo)) reveals increased contamination from elements in the first two groups in recent years. Element concentrations, compared with the Effects Range-Low (ERL) and Effects Range-Median (ERM) levels set by NOAA, suggest that adverse biological effects from Ni contamination are very likely.