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Hyperspectral images (HSIs) are inevitably degraded in the acquisition process by mixed noise including Gaussian noise, impulse noise, stripes, and so on. Recently, many low-rank regularization based HSI restoration methods have been proposed to powerfully remove the mixed noise. However, most of them use the square patch based denoising strategy, which destroyed the boundary information of the objects in the HSI. In this paper, we adopt superpixel segmentation to group the pixels of HSI with adjacent position, similar color, texture and luminance into a homogeneous region, whose shape is adaptive. Several homogeneous regions cover the full HSI. This is better than simply dividing the HSI into square patches. By taking advantage of both the low-rank property and the spectral smooth of the HSI, this approach can efficiently remove the mixed noise with few time. Several experiments verify the performance of the proposed approach for HSI restoration.

A microfluidic platform based on the integration of denaturation and online immobilized enzyme reactor (IMER) digestion for protein pretreatment was first developed on a glass chip. The design of three inlet channels and two groups of snake channel in glass chip can allow the protein solution, the reducing reagent and the alkylating agent to be simultaneously injected into the chip channel and ensured the reaction solution on-line efficient mixing and sufficient reacting. By thiol-ene click chemistry, the capillary-based and glass chip-based trypsin IMER on the surface of poly(trimethylolpropane trimethacrylate) monolith were fabricated. The wide range of flow rate tolerance (0.8–5.0 μL/min), and the acceptable reproducibility (RSD% = 3.1%, n = 5) and stability (13.8% decrease of enzyme activity in 2 months) indicated the feasibility of using IMER for online digestion of proteins. Compared with the solution denaturation-offline IMER digestion, the integrated microfluidic platform of chip denaturation-chip IMER and chip denaturation-online IMER have comparable protein identification ability for mouse liver protein with a similar number of protein (798 or 826 vs. 843) and unique peptides (3923 or 4593 vs. 3916). More importantly, the easy and fast digestion of protein samples and possible combination with MS revealed that this microfluidic platform can be a potential method for rapid proteomics analysis.

Three novel ferrocene appended naphthalimide derivatives (2a, 2b and 6) were synthesized and characterized by IR, 1H NMR and mass spectroscopies. In electrochemical experiments, all of the ferrocene appended naphthalimide derivatives exhibited reversible one-electron oxidation in CV curves. And the DNA binding ability of the compounds was studied by ethidium bromide displacement experiments and UV–visible spectrophotometry. The ferrocene appended naphthalimide derivative 6 also exhibited the highest DNA binding ability in all the tested compounds. According to the viscosity results, all of the synthesized compounds displayed the partial intercalation binding mode to DNA duplex. Bis-naphthalimide compound 5 was used as reference compound to evaluate the synergistic effect of the ferrocene group in ferrocene appended naphthalimide derivative 6. The cytotoxicity of the synthesized compounds against 4 different human cancer cell lines (EC109, BGC823, SGC 7901 and HepG2) was studied by MTT assay. The ferrocene appended bis-naphthalimide derivative 6 showed the best cytotoxicity against tested human cancer cells in all the synthesized naphthalimide derivatives and control drug amonafide. The uptake of naphthalimide derivative 6 was proved by laser confocal images. In addition, the DNA damage induced by naphthalimide derivative 6 was studied by comet assay.

Among boron-containing fluorescent probes, fluorescein modified by dihydroxyboron is rarely reported as a probe for detecting contaminants. For the first time, a non-covalent ratiometric fluorophore (NRF) was synthesized based on the interactive reaction between 4,5-bis-dihydroxyboron fluorescein and dibenzofuran. The optimized synthetic conditions for NRF were 1 mmol% Ni(dppp)Cl2 as a catalyst, 5 mmol% PPh3 as an additive, room-temperature reaction, and 72-h stirring, and in such cases, the yield reached as high as 91%. At the 290-nm excitation wavelength, the NRF molecules produced dual-emitting phenomenon at 315 and 560 nm. When fenpropathrin as a representative species of pyrethroid pesticides (Pys) was added, the 315-nm fluorescence intensities (FIs) were dramatically decreased, whereas the 560-nm FIs were slightly changed. Therefore, the ratios (I560/I315) of 560-nm FIs to 315-nm FIs could be utilized as an appropriate ratiometric indicator for sensitive Pys detection. Optimized conditions for the ratiometric probe were 60-min incubation and neutral solution pH; under such circumstances, the linear range, limit of detection and fortified recoveries for Pys were 5–150 μg·L−1, 1.5 μg·L−1 and 97.55–105.90%, respectively, which are comparable or even better than those of previously reported methods. As verified by certified reference material in apple juice (QC-198B-1), the NRF probe yielded a highly relative recovery up to 98.25% for fenpropathrin. Common salts and other pesticides had little effect on the ratiometric indicator of NRF, evidencing good selectivity and specificity for Pys. Collectively, this ratiometric probe shows great prospects in application for trace-level Pys detection in daily food monitoring.

An ultrasensitive and stable "dual-potential" ratiometric electrochemiluminescence (ECL) sensor is reported for specific DNA, the femtomolar detection limit (0.12 fM, S/N = 3) and high selectivity insure its potential applications in cancer biomarkers searching or monitoring. The excellent performance of the sensor comes from simultaneously fabricated layer by layer structure "target DNA + Hemin / Au-Luminol NPs / DNA* / sl DNA / TGA / QDs / MWNTs / GCE" mode which was based on the enhancing effect of luminol by G-quadruplex / hemin and Au nanoparticles and the quenching effect of CdSe/ZnS by G-quadruplex / hemin. (i) DNA-SH could combine with Au-Luminol NPs via S-Au bond to solve the problem of poor solubility and weak ECL intensity of luminol in neutral medium. (ii) Target DNA and Hemin formed the G-quadruplex / hemin peroxidase mimicking DNAzyme could enhance the ECL of luminol and quench the ECL of CdSe/ZnS simultaneously. (iii) DNA* was employed to increase a certain distance between CdSe/ZnS and Au-Luminol for enhancing the CdSe/ZnS QDs initial ECL intensity. The dual-potential ratiometric mode lower the influence of background and side reaction of the ECL sensor which were the most important factors in trace sensing.

Powdery mildew, caused by Blumeria graminis f. sp. tritici (Bgt), is one of the most damaging diseases to wheat in the world. The cultivation of resistant varieties of wheat is essential for controlling the powdery mildew epidemic. Wheat landraces are important resources of resistance to many diseases. Mapping powdery mildew resistance genes from wheat landraces will promote the development of new varieties with disease resistance. The Chinese wheat landrace Baiyouyantiao possesses characteristic of disease resistance to powdery mildew. To identify the resistance gene in this landrace, Baiyouyantiao was crossed with the susceptible cultivar Jingshuang 16 and seedlings of parents and F1, BC1, F2, and F2:3 were tested with Bgt isolate E09. The genetic results showed that the resistance of Baiyouyantiao to E09 was controlled by a single recessive gene, tentatively designated PmBYYT. An Illumina wheat 90K single-nucleotide polymorphism (SNP) array was applied to screen polymorphisms between F2-resistant and F2-susceptible DNA bulks for identifying the chromosomal location of PmBYYT. A high percentage of polymorphic SNPs between the resistant and susceptible DNA bulks was found on chromosome 7B, indicating that PmBYYT may be located on this chromosome. A genetic linkage map of PmBYYT consisting of two simple sequence repeat markers and eight SNP markers was developed. The two flanking markers were SNP markers W7BL-8 and W7BL-15, with genetic distances of 3 and 2.9 cM, respectively. The results of this study demonstrated the rapid characterization of a wheat disease resistance gene and SNP marker development using the 90K SNP assay. The flanking markers of gene PmBYYT will benefit marker-assisted selection (MAS) and map-based cloning in breeding wheat cultivars with powdery mildew resistance.

Objectives This study aimed to identify patients with major depressive disorder (MDD) by developing different machine learning (ML) models based on tryptophan hydroxylase-2 (TPH2) methylation and environmental stress. Methods The data were collected from 291 patients with MDD and 100 healthy control participants: individual basic information, the Negative Life Events Scale (NLES) scores, the Childhood Trauma Questionnaire (CTQ) scores and the methylation level at 38 CpG sites in TPH2. Information gain was used to select critical input variables. Support vector machine (SVM), back propagation neural network (BPNN) and random forest (RF) algorithms were used to build recognition models, which were evaluated by the 10-fold cross-validation. SHapley Additive exPlanations (SHAP) method was used to evaluate features importance. Results Gender, NLES scores, CTQ scores and 13 CpG sites in TPH2 gene were considered as predictors in the models. Three ML algorithms showed satisfactory performance in predicting MDD and the BPNN model indicated best prediction effects. Conclusion ML models with TPH2 methylation and environmental stress were identified to possess great performance in identifying patients with MDD, which provided precious experience for artificial intelligence to assist traditional diagnostic methods in the future.

The early Paleozoic sediments document two major biological events: the Great Ordovician Biodiversification Event (GOBE) and Late Ordovician mass extinction (LOME). Many investigations have focused on taxonomic richness patterns during these major diversification and extinction events, providing insights into their timings and potential causes. However, the coarse temporal resolutions used in previous investigations hampered their ability to document fine-scale patterns. To address these issues, we employed CONOP analysis to data collected from a large suite of southern Chinese stratigraphic successions to construct a high-resolution (temporal resolution of ~21.0 Kyr) regional chronostratigraphy and document species richness dynamics during the middle–late Cambrian to early Silurian interval. Our results showed that the GOBE began in the early Tremadocian and ended at the Dapingian–Darriwilian boundary and consisted of two major radiation phases. The main pulse of GOBE, which lasted from the late Floian to the earliest Darriwilian, exhibited a species richness increase with elevated origination and extinction rates. Major marine groups showed no significant diachroneity during the GOBE, with most presenting richness peaks in this event's main pulse of the GOBE. Plankton demonstrated a significant diversification from the late Cambrian to the GOBE climax and subsequently dominated the marine realm in South China. Marine life experienced two extinction events in the Late Ordovician, the Katian extinction and Hirnantian extinction, which resulted in a regional species loss of ~67%.

A series of tripodal ferrocenyl bis-naphthalimide derivatives were synthesized and characterized. All of the bis-naphthalimide derivatives exhibited good DNA binding ability which was confirmed by ethidium bromide (EB) displacement experiment and ultraviolet (UV)-visible absorption titration. And the binding mode of these compounds was proved to be a hybrid binding mode by experiments. The cytotoxicity of synthesized compounds against 4 different human cancer cell lines (EC109, BGC823, SGC7901 and HEPG2) was evaluated by thiazolyl blue tetrazolium bromide (MTT) assay. All of the bis-naphthalimide derivatives exhibited good anticancer activity than the positive control drug (amonafide), which was due to the promotion of reactive oxygen species (ROS) level in test cancer cells by the reversible one-electron redox process of ferrocenyl bis-naphthalimide derivatives. Although there was no obvious relationship between the binding constants and the chain length, the structure cytotoxicity relationship revealed that the linker of n = 3, m = 1 was the best choice for the tested tripodol bis-naphthalimide derivatives. Synopsis A series of tripodal ferrocenyl bis-naphthalimide derivatives were synthesized to study the DNA binding ability and the cytotoxicity induced by reactive oxygen species. All of the compounds exhibited good DNA binding ability. And the structure cytotoxicity relationship revealed that the structure of 5h was the best choice.

Joint sparsity has attracted considerable attention in recent years in many fields including sparse signal recovery in compressive sensing, statistics, and machine learning. Traditional convex models with joint sparsity suffer from the suboptimal performance though enjoying tractable computation. In this paper, we propose a new non-convex joint sparsity model, and develop a corresponding multi-stage adaptive convex relaxation algorithm. This method extends the idea of iterative support detection (ISD) from the single vector estimation to the multi-vector estimation by considering the joint sparsity prior. We provide some preliminary theoretical analysis including convergence analysis and a sufficient recovery condition. Numerical experiments from both compressive sensing and multi-task feature learning show the better performance of the proposed method in comparison with several state-of-the-art alternatives. Moreover, we demonstrate that the extension of ISD from the single vector to multi-vector estimation is not trivial. While ISD does not well reconstruct the single channel sparse Bernoulli signal, it does achieve significantly improved performance when recovering the multi-channel sparse Bernoulli signal thanks to its ability of natural incorporation of the joint sparsity structure.

The plant macrofossils from the Lower Jurassic coal-bearing Hongqi Formation in the Xilinhot Basin, central Inner Mongolia of North China, are systematically documented for the first time. The flora contains 40 species of 21 genera, belonging to horsetails, ferns, Cycadopsida, Ginkgopsida, conifers, and isolated seeds of unknown affinity. The Filicopsida, predominant in the flora, are characterized by high species diversity of form genus Cladophlebis (with 12 species), abundant Hausmannia ( Protorhipis ) of the Dipteridaceae, and existence of Coniopteris and Eboracia of the Dicksoniaceae. Among the gymnosperm group, the Ginkgopsida rank the second of the flora, with nine species representing Ginkgoites , Sphenobaiera of ginkgoales and Phoenicopsis , Czekanowskia of czekanowskiales. The Cycadopsida consist of six species, four of which belong to genera Anomozamites , Pterophyllum , Nilssoniopteris , and Ptilophyllum of bennettitales and the other two to Nilssonia and Ctenis of cycadaleans. Conifers, with a relatively smaller number of species, are characterized by long and broad leaves, including genera Podozamites , Elatocladus , and Pityophyllum . Based on the stratigraphical ranges of the known species, the existence of Coniopteris and Eboracia , and the abundance of Hausmannia and Cladophlebis , the age of the studied flora can be determined as late Early Jurassic and possibly the Toarcian. The existence of climate sensitive elements, particularly the thermophilous plants such as the dipteridaceous fern Hausmannia , bennettitales Ptilophyllum , further demonstrates that the climate of Xilinhot area during the late Early Jurassic was warm and humid, but could be hot and even arid as in the subtropic zone at short intervals. It was warmer than during both the early Early Jurassic and early Middle Jurassic, indicating a temperature rising event occurred in the late Early Jurassic. Palaeobotanical and sedimentary data also support the conclusion that a warming and somewhat arid climatic event occurred in the terrestrial area of North China. This climate change event was coincided possibly with the Toarcian Oceanic Anoxic Event (T-OAE), and could be the response of the terrestrial ecological system to the great and rapid change of palaeoenvironment in the marine ecosystem.

Methods based on low-rank regularization have been successfully used to decompose an image into its cartoon and texture components. However, most of the existing low-rank regularized methods are formulated as a convex nuclear norm minimization, which is in practice suboptimal due to equally punishing each singular value. Recent works have shown that non-convex low-rank approximations adaptively treating the singular values at different scales yield better results than those convex ones. In this paper, we consider a non-convex log det function as the low-rank regularization to characterize the texture component in image decomposition, which treats singular values with varying degrees to facilitate a better characterization of the texture component. Then we obtain a non-convex cartoon–texture image decomposition model, where the cartoon and texture components are characterized simultaneously by minimizing the total variation norm and log det function. We integrate the self-similarity of texture component and the piecewise smooth of cartoon component into one model. The model can handle various types of image degradations, including blur, missing pixels and noise. Moreover, we develop an efficient alternating direction method of multiplier to solve the proposed model. The proposed method gives both a decomposition of cartoon and texture components and the restored image. Results of numerical experiments demonstrate the outstanding performance of the proposed method in image decomposition.

A new macroporous immobilized trypsin reactor (IMER) based on high internal phase emulsion (HIPE) monolith has been designed in view of fast mass transfer of macromolecule. The concentrated emulsion consisted of a mixture of glycidyl methacrylate, divinylbenzene and deionized water, in which contained a suitable surfactant and an initiator. The resulting polyHIPE monolith was sequentially modified with ammonia and gold nanorods (AuNRs). Finally, trypsin was immobilized on the surface of the monolith by forming Au-S bonds between the AuNRs and the free thiol groups of trypsin. The digestion time of bovine serum albumin (BSA) on the IMER has been greatly shortened than that of in-solution digestion (10 min vs. 12 h), and the number of detected peptides has been significantly increased (114 vs. 84) with the sequence coverage improved effectively (91.6% vs. 82.7%). By digestion of the proteins extracted from rat livers with the IMER, 1127 protein groups (6901 peptides) were identified by liquid chromatography-tandem mass spectrometry (LC–MS/MS). All these results above suggested that the monolithic IMER with open pore structure in place of monolith with conventional structures of particle packing can improve the efficiency of digestion of proteins significantly and has great application potential in proteomics analysis.

Microbial fermentation can endow food with unique flavors, increase its nutritional value and enhance functional characteristics. Our previous research has shown that liquid fermentation of soymilk by Bacillus subtilis BSNK-5 imparted new functional properties of to the fermented product via production of nattokinase. In this study, in order to further investigate the changes in the flavor, nutritional quality and functional characteristics of soymilk during fermentation using proton nuclear magnetic resonance (1H NMR) metabolomics to monitor the metabolite profile of BSNK-5-fermented soymilk. A total of 44 differential metabolites were identified between BSNK-5-fermented soymilk and uninoculated/unfermented soymilk, among which the levels of flavor-related substances (acetate, isovalerate and 2-methylbutyrate), nutrient-related substances (12 free amino acids), and functional substances (taurine, GABA and genistein) significantly increased after fermentation. These metabolites were closely associated with eight potential metabolic pathways. This work highlighted the significance of BSNK-5 strain in improving the nutritional quality and functional characteristics of fermented soymilk; however, the use of the strain also caused flavor deterioration. This study lays a theoretical foundation for the improvement and development of fermented soy products via liquid fermentation with B. subtilis.

Six new pidz-based bis-cyclometalated Ir(III) complexes (Ir1-Ir6) have been synthesized and characterized. These complexes contain 2-phenyl-2H-indazole (pidz, 2a), 2-(4-fluorophenyl)–2H-indazole (fpidz, 2b), 2-(p-tolyl)–2H-indazole (ch3pidz, 2c), 2-(4-(trifluoromethyl)phenyl)–2H-indazole (cf3pidz, 2d), 2-(2,4-difluorophenyl)–2H-indazole (2,4-f2pidz, 2e) and 2-(3,5-difluorophenyl)–2H-indazole (3,5-f2pidz, 2f) as cyclometalated (C∧N) ligands, and acetylacetone (acacH) as ancillary ligand. The crystal structure of Ir2 has been determined by X-ray analysis. Different substituents of C∧N ligand in Ir2-Ir6 induce either a bathochromic or hypsochromic shift in the absorption spectra relative to the parent complex Ir1. The phenomenon is further well explained by DFT calculation and electrochemical study. All of the iridium(III) complexes are yellow emissive with quantum yields of 13.1–32.3% and lifetimes of 1.32–1.77 μs in solution at room temperature. We demonstrate that their emission originates from a hybrid 3MLCT/3ILCT/3LLCT excited state on the basis of the experimental and theoretical investigation. The corresponding yellow-emitting devices based on complexes Ir1, Ir2 and Ir4 can produce efficient electrophosphorescence with a luminance efficiency of 35.1–52.2 cd·A-1, a power efficiency of 20.8–32.1 lm·W−1 and an external quantum efficiency of up to 25.6%. All these EL data definitely suggest the bulky –CF3 skeleton in the doped materials could benefit the fabrication of high-efficiency phosphorescent OLEDs.

A novel immobilized enzyme reactor (IMER) based on trimethylolpropane trimethacrylate (TRIM) organic monolith was prepared by “thiol-ene” click reaction. The IMERs were made by fabricating TRIM monolith core in advance. There were residual double bonds on the surface of TRIM monolith, in which click reaction can be performed with the free thiol groups of trypsin at room temperature to bond the trypsin on the monolithic column without additionally introducing an active functional group. The enzyme activity was characterized by kinetic parameters Km and Vmax and determined by off-line chromatography. The performance of the IMERs was evaluated by digesting standard protein BSA and compared with in-solution digestion method. By using IMER 5 min, the sequence coverage rate of BSA was 79.41%, which was similar to that in-solution digestion for 12 h (82.7%). The applicability of the IMERs in complex samples was assessed by digesting crude protein extracts from egg white and mouse liver, identifying 28 (104 peptides) and 843 (3916 peptides) proteins, respectively. All results indicated that the IMERs have great potential in high-throughput proteomics analysis.

Samples of Upper Ordovician marine carbonates from four sections on the Yangtze Platform (1, the Liangcun section northeast of Xishui County Town, Guizhou Province; 2, the Zhuazhuayan section southwest of Leibo County Town, Sichuan Province; 3, the Xiaogangwan section east of Wulong County Town, Chongqing Municipality; 4, the Shatan section north of Nanjiang County Town, Sichuan Province) have been analyzed for carbon isotope (δ 13 C) chemostratigraphy. A distinct positive δ 13 C excursion (δ 13 C max > 2) is observed in all sections, which ranges through the Hamarodus brevirameus conodont zone, and locally into slightly younger strata. The base of this zone is the First Appearance Datum (FAD) of H. brevirameus and its top coincides with the FAD of the conodont Protopanderodus insculptus . Based on its position in the H. brevirameus zone, this excursion is identified as the well-known Guttenberg Excursion (GICE) confirming the global significance of this paleoceanographic event. The fact that in the Black Knob Ridge section in the USA, the GSSP of the base of the global Katian Stage, the beginning of the GICE is just below the base of the Katian makes it possible to locate this key level in our study sections even in the absence of the diagnostic graptolite Diplacanthograptus caudatus . Our carbon curves through the GICE interval show three minor secondary peaks reflecting paleoceanographic changes or selective preservation of the isotope signal. However, because a global review of the GICE shows that such minor peaks, which are often based on a single elevated δ 13 C value, are of irregular occurrence, they are interpreted as local, rather than global, phenomena. The suggested global cooling in the early Katian might have favored the generation of methane hydrates and hence the reduction of the amount of 12 C in the marine carbonates.

In this study, an electrochemical sensor of nitro aromatic compound based on three-dimensional porous Pt-Pd nanoparticles (Pt-Pd NPs) supported by reduced graphene oxide (rGO) nanosheets-multiwalled carbon nanotube (CNTs) nanocomposite (marked as Pt-Pd NPs/CNTs-rGO) was investigated for the first time. This hybrid nanocomposite has been prepared via a facile and versatile hydrothermal synthetic strategy while its structure and property are evaluated by X-ray diffraction (XRD), transmission electron microscopy (TEM) and electrochemical impedance spectroscopy (EIS). The result shows that 3D porous Pt-Pd NPs/CNTs-rGO nanocomposite has a large specific surface area of 326.6m(2)g(-1) and exhibited ultrahigh rate capability and good cycling properties at high rates. Electrochemical studies have been performed for the nitro aromatic compounds detection by using different pulse voltammetry (DPV) techniques. The proposed nanocomposite exhibited much enhanced elctrocatalytic activity and high sensitivity toward the detection of nitro aromatic compounds which compared with Pt-Pd NPs dispersed on functionalized rGO, Pt-Pd NPs dispersed on functionalized CNTs, rGO-CNTs and bare glass carbon electrode (GCE). On the basis of the above synergetic electrochemical sensing and synthesis procedure, the hybrid material can be recommended as a robust material for sensor-related applications. Moreover, the proposed sensor exhibits high reproducibility, long-time storage stability and satisfactory anti-interference ability.

In this study, a simple and sensitive electrochemical analytical method is developed for simultaneous detection of hydroquinone (HQ) and catechol (CC) employing the three-dimensional functionalized graphene (3DFG) modified glass carbon electrode (GCE). The 3DFG modified electrode can distinguish between HQ and CC, with higher oxidation currents in comparison with bare GCE and two-dimensional graphene (Gr) modified electrode, showing the enhanced catalytic activity. The differential pulse voltammetry (DPV) shows that the isomers can be detected sensitively and selectively at 3DFG/GCE with peak-to-peak separation about 100 mV. Under the optimized conditions, the oxidation peak current increases linearly with concentration of HQ ranged from 3.10 × 10 −7 to 1.31 × 10 −5 M and concentration of CC ranged from 2.50 × 10 −7 to 1.29 × 10 −5 M, respectively. The detection limits are 1.0 × 10 −7 M and 8.0 × 10 −8 M for HQ and CC (S/N = 3), respectively. Moreover, the proposed method has been successfully applied to the simultaneous determination of HQ and CC in real water samples with satisfactory recoveries.

Nitrogen-doped carbon microfibers (N-CMFs) with porous textures have been synthesized by means of a floating catalyst chemical vapor deposition (FCCVD) with anhydrous ferric chloride as a catalyst precursor and melamine as both the carbon and nitrogen source. X-ray photoelectron spectroscope (XPS) characterization of the as-prepared N-CNFs reveals nitrogen atoms in the N-CMFs are mainly in the form of pyridine-like nitrogen and graphitic nitrogen. The sublimation and subsequent gas phase reduction of FeCl3 in H2 produces Fe micro-particles with high catalytic activity that leads to the growth of the microfibers. The electrochemical studies have shown that N-CMFs have a larger capacitance than the pure CMFs, showing promise for use as electrode materials in supercapacitors.

Conodonts from the Cambrian–Ordovician transition at the Liangcun section in Xishui County, Guizhou and at the Huangcao section in Wulong County, Chongqing are examined for the first time. Both sections are located at the southeast margin of the Sichuan Basin. A total of 1367 specimens were recovered, representing 30 species and 15 genera. Based on the ranges of conodonts generalized from these two sections and another six sections previously studied in the same region, three conodont zones, Cordylodus proavus, Monocostodus sevierensis and Cordylodus angulatus zones are recognized. The index species of the Cambrian–Ordovician boundary at the global stratotype section and point (GSSP), Iapetognathus fluctivagus and its substitute in China Iapetognathus jilinensis are not observed in the study sections, therefore it is impossible to determine the Cambrian–Ordovician boundary exactly. However, it probably lies within the lower part of M. sevierensis zone (the upper part of the Loushanguan Group), correlating with the GSSP in Canada and the Dayangcha section in China. Chronological sequences of the FAD (First Appearance Datum) of C. angulatus , Chosonodina herfurthi and Rossodus manitouensis are not obvious in the study, so the C. angulatus zone here is correlated with zones defined by C. angulatus , Ch. herfurthi and R. manitouensis in the lower Yangtze Platform.

Graphene was produced from graphene oxide using sodium citrate as the reducing agent under mild conditions. The products were characterized by scanning electron microscopy, X-ray diffraction, ultraviolet visible absorption spectroscopy and Fourier transform infrared spectrometry. Results indicate that the electrical conductivity of graphene oxide was increased by over three orders of magnitude after reduction with sodium citrate, and the obtained graphene showed nonlinear I-V curves.