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Carbonate strata are a vital and favorable reservoir for global oil and gas exploration, and carbonate sedimentary systems record ancient oceanic and paleoclimatic conditions, including paleoenvironmental variations throughout geologic periods. Carbonate platforms are widely distributed among the Xisha Islands in the South China Sea and contain large amounts of oil and gas resources. Biogenic reefs are the dominant parts of the carbonate platforms in the Xisha Islands; however, research on the factors that control and affect biogenic reef development is lacking. In this study, a core from well XK-1, which is located on Yongxing Island in the Xisha Islands, a sedimentary noise model, and time-series analyses were used to determine the effects of sea-level fluctuations from 5.3 Ma to present. The results show that coral reefs in the Xisha Islands are sensitive to eustatic fluctuations and that a decrease in sea level essentially corresponds to an increase in sedimentation rate. Indexes of the East Asian monsoon and other environmental indexes show that the Pleistocene and Holocene were suitable for coral growth; however, the trends shown by these indexes and the sea-level variation indicate that the future growth of coral reefs will be at a disadvantage. Research on the controlling factors of biogenic reefs is of significance for understanding reef growth, performing global reef comparisons, and encouraging the future protection of coral reefs.

Swertiamarin, a natural ingredient with potent pharmacological activities in the iridoid glycoside family, had been reported to have significant therapeutic effects on a variety of human diseases.In this study, a systematic and efficient strategy based on UHPLC-Q-Exactive Orbitrap mass spectrometry was established to reveal the metabolic profile of swertiamarin in rat urine, plasma, and faeces.First of all, post-acquisition data-mining methods, including multiple mass defect filters (MMDFs) and high-resolution extracted ion chromatograms (HREICs), were developed to screen the metabolite candidates of swertiamarin from the complete mass scan data sets.Second, according to the diagnostic product ions (DPIs), neutral loss fragments (NLFs), chromatographic retention time, accurate mass measurement and calculated Clog

Trichosporon fermentans can be used to treat refined soybean oil wastewater (RSOW) and produce microbial lipids. Bioflocculation is an effective method to recover Trichosporon fermentans which accumulates intracellular oils from wastewater. During the flocculation, the hydrodynamic distribution and parameters in the reactor are important limiting factors of yeast flocculation performance. In a 0.25 L flocculation device, it was found that the appropriate range of turbulence kinetic energy was within 0.00065-0.00073 m

The direct counterfactual quantum communication protocol involving double chained Mach-Zehnder interferometers requires a single photon input. Here, we show that even with multiphoton light sources, including a strong coherent light source as inputs, the counterfactual communication can be achieved with success probability approaching unity in the ideal asymptotic limit. The path evolution of multiple photons is non-locally controlled. Thus, information is transmitted without any photons, or any other auxiliary information carriers, appearing in the public transmission channel. The effect is quantum since quantum measurements are essential requirement for this protocol. Furthermore, a modified scheme is proposed in which number of interferometers is reduced.

The metabolites of salvianolic acid A and salvianolic acid B in rats were analyzed and compared by ultra-high-perfor-mance liquid chromatography with linear ion trap-orbitrap mass spectrometry(UHPLC-LTQ-Orbitrap MS). After the rats were administrated by gavage, plasma at different time points and urine within 24 hours were collected to be treated by solid phase extraction(SPE), then they were gradient eluted by Acquity UPLC BEH C_(18) column(2.1 mm×100 mm, 1.7 μm) and 0.1% formic acid solution(A)-acetonitrile(B) mobile phase system, and finally all biological samples of rats were analyzed under negative ion scanning mode. By obtaining the accurate relative molecular mass and multi-level mass spectrometry information of metabolites, combined with the characteristic cleavage law of the reference standard and literature reports, a total of 30 metabolites, including salvianolic acid A and B, were identified. Among them, there were 24 metabolites derived from salvianolic acid A, with the main metabolic pathways including ester bond cleavage, dehydroxylation, decarboxylation, hydrogenation, methylation, hydroxylation, sulfonation, glucuronidation, and their multiple reactions. There were 15 metabolites of salvianolic acid B, and the main biotransformation pathways were five-membered ring cracking, ester bond cleavage, decarboxylation, dehydroxylation, hydrogenation, methylation, sulfonation, glucuronidation, and their compound reactions. In this study, the cross-metabolic profile of salvianolic acid A and B was elucidated completely, which would provide reference for further studies on the basis of pharmacodynamic substances and the exploration of pharmacological mechanism.

Result relevance prediction is an essential task of e-commerce search engines to boost the utility of search engines and ensure smooth user experience. The last few years eyewitnessed a flurry of research on the use of Transformer-style models and deep text-match models to improve relevance. However, these two types of models ignored the inherent bipartite network structures that are ubiquitous in e-commerce search logs, making these models ineffective. We propose in this paper a novel Second-order Relevance, which is fundamentally different from the previous First-order Relevance, to improve result relevance prediction. We design, for the first time, an end-to-end First-and-Second-order Relevance prediction model for e-commerce item relevance. The model is augmented by the neighborhood structures of bipartite networks that are built using the information of user behavioral feedback, including clicks and purchases. To ensure that edges accurately encode relevance information, we introduce external knowledge generated from BERT to refine the network of user behaviors. This allows the new model to integrate information from neighboring items and queries, which are highly relevant to the focus query-item pair under consideration. Results of offline experiments showed that the new model significantly improved the prediction accuracy in terms of human relevance judgment. An ablation study showed that the First-and-Second-order model gained a 4.3% average gain over the First-order model. Results of an online A/B test revealed that the new model derived more commercial benefits compared to the base model.

Reinforcement learning based recommender systems (RL-based RS) aim at learning a good policy from a batch of collected data, by casting recommendations to multi-step decision-making tasks. However, current RL-based RS research commonly has a large reality gap. In this paper, we introduce the first open-source real-world dataset, RL4RS, hoping to replace the artificial datasets and semi-simulated RS datasets previous studies used due to the resource limitation of the RL-based RS domain. Unlike academic RL research, RL-based RS suffers from the difficulties of being well-validated before deployment. We attempt to propose a new systematic evaluation framework, including evaluation of environment simulation, evaluation on environments, counterfactual policy evaluation, and evaluation on environments built from test set. In summary, the RL4RS (Reinforcement Learning for Recommender Systems), a new resource with special concerns on the reality gaps, contains two real-world datasets, data understanding tools, tuned simulation environments, related advanced RL baselines, batch RL baselines, and counterfactual policy evaluation algorithms. The RL4RS suite can be found at https://github.com/fuxiAIlab/RL4RS. In addition to the RL-based recommender systems, we expect the resource to contribute to research in applied reinforcement learning., Comment: 4-th version, SIGIR2023

A method of ultra-high performance liquid chromatography coupled with quadrupole/electrostatic field Obitrap high-resolution mass spectrometry(UHPLC-Q-Exactive MS) was established to comprehensively identify the metabolites of carnosic acid in rats. After oral gavage of carnosic acid CMC-Na suspension in rats, urine, plasma and feces samples were collected and pretreated by solid phase extraction(SPE). Acquity UPLC BEH C_(18 )column(2.1 mm×100 mm, 1.7 μm) was used with 0.1% formic acid solution(A)-acetonitrile(B) as the mobile phase for the gradient elution. Biological samples were analyzed by quadrupole/electrostatic field Obitrap high-resolution mass spectrometry in positive and negative ion mode. Based on the accurate molecular mass, fragment ion information, and related literature reports, a total of 28 compounds(including carnosic acid) were finally identified in rat samples. As a result, the main metabolic pathways of carnosic acid in rats are oxidation, hydroxylation, methylation, glucuronide conjugation, sulfate conjugation, S-cysteine conjugation, glutathione conjugation, demethylation, decarbonylation and their composite reactions. The study showed that the metabolism of carnosic acid in rats could be efficiently and comprehensively clarified by using UHPLC-Q-Exactive MS, providing a reference for clarifying the material basis and metabolic mechanism of carnosic acid.

Table S1. The effect of IMB0901 on the weights of body, quadriceps, gastrocnemius, WAT, and BAT when administered in healthy mice. (DOCX 16 kb)

For decades, the edible mushroom Pleurotus eryngii (P. eryngii) has been cultivated as important raw materials for food and pharmaceutical industries in most of Asian countries, especially in China. Unfortunately, the generation and improvement of new cultivars are very difficult since there are many barriers which have not been solved thoroughly by gene editing tools, even though the CRISPR-Cas9 technique has been widely applied in other species. In this study, we identified the point-mutated variant of the endogenous sdhB gene (cbxr) as a more stable selection marker than hygromycin B resistance gene (hph) in P. eryngii. Furthermore, using a codon-optimized Cas9, a predicted native U6 promoter-guided sgRNA, as well as an optimized protoplast transformation system, a highly efficient pyrG gene editing system was established in P. eryngii, that incorporated varied insertions and deletions (indels) by non-homologous end joining (NHEJ) and homology-directed repair (HDR). Findings for a successful targeted gene editing strategy in the edible mushroom P. eryngii may open a new chapter for the improvement of edible mushroom cultivars.

Magnolol, an essential bioactive natural lignans isolated from Magnolia Officinalis, has various pharmacological activities, such as antibacterial, anti-inflammatory, antioxidation and anti-tumor. In this study, a practical strategy based on ultra-high-performance liquid chromatography coupled with linear ion trap-Orbitrap mass spectrometry (UHPLC-LTQ-Orbitrap MS) was established to reveal the metabolic fate of magnolol in rat plasma and urine. First of all, in the data-dependent scanning (DDS) acquisition mode, the ESI-MSn data sets of biological samples and reference standard were obtained by using a high-quality online data analysis method. Subsequently, off-line data-mining techniques including multiple mass defect filters (MMDFs) and high-resolution extracted ion chromatograms (HREICs) were applied to screen major-to-trace metabolites of magnolol at the full-scan ESI-MS1 level. Finally, a total of 177 metabolites (prototype compound included) were preliminarily observed and characterized according to accurate mass measurement, the characteristic fragmentation patterns, chromato-graphic behaviors, and corresponding Clog P values. The results showed that magnolol experienced a variety of biotransformation reactions in rats, including hydroxylation, methoxylation, dehydrogenation, carboxylation, sulfonation, glucuronide conjugation, glucose conjugation, N-acetylcysteine (NAC) conjugation, glutathione conjugation and their composite reactions. In conclusion, this study not only greatly expanded the understanding of the therapeutic material basis and pharmacological mechanism of magnolol, but also provided new ideas for its toxicity evaluation, safety monitoring and drug delivery forms design.

This paper proposes a new HDP based online review rating regression model named Topic-Sentiment-Preference Regression Analysis (TSPRA). TSPRA combines topics (i.e. product aspects), word sentiment and user preference as regression factors, and is able to perform topic clustering, review rating prediction, sentiment analysis and what we invent as "critical aspect" analysis altogether in one framework. TSPRA extends sentiment approaches by integrating the key concept "user preference" in collaborative filtering (CF) models into consideration, while it is distinct from current CF models by decoupling "user preference" and "sentiment" as independent factors. Our experiments conducted on 22 Amazon datasets show overwhelming better performance in rating predication against a state-of-art model FLAME (2015) in terms of error, Pearson's Correlation and number of inverted pairs. For sentiment analysis, we compare the derived word sentiments against a public sentiment resource SenticNet3 and our sentiment estimations clearly make more sense in the context of online reviews. Last, as a result of the de-correlation of "user preference" from "sentiment", TSPRA is able to evaluate a new concept "critical aspects", defined as the product aspects seriously concerned by users but negatively commented in reviews. Improvement to such "critical aspects" could be most effective to enhance user experience.

Time delay estimation is the key to acoustic source localization based on time delay, and the time difference caused by the difference of the same signal arriving at different microphone distances is estimated. The main algorithms now include generalized phase days method, adaptive least mean method, the cross power spectrum phase method and so on, all of them get the time delay essentially by seeking the maximum position of the cross-correlation function. This paper discusses several of the above algorithms, and compares their advantages and disadvantages.

Sound source localization technology is a kind of positioning technology that use acoustics and electronic devices to receive acoustic waves to determine the location of sound source. In recent years, it has been widely used, and this paper discusses the application status, development prospect and difficulties and challenges of sound source localization technology.

Based on time delay,Sound source localization method has a smaller amount of calculation compared with the sound source localization method of controllable beam synthesizer and high resolution spectral estimation, and can achieve a higher positioning accuracy after improved, so it is the most suitable method for real-time positioning, widely used in the field of passive acoustic localization. This paper tries to spread the factors that affect the positioning accuracy of time delay method, and provides the direction for improving the effect of time delay sound source localization.

With the rapid development of nanotechnology, nanomaterials have been used in numerous fields. However, these nanomaterials could also result in risk for human and environmental health. To make a comparison of the health effects of three different kinds of nanomaterials, 28 male BALB/c mice were randomly divided into four groups. Three experimental groups were exposed to different kinds of nanomaterials including graphene, graphene oxide and single wall carbon nanotubes (SWCNTs) by intraperitoneal injection while the control group received a saline injection. The exposure dose of experimental groups was 4mg/kg. After seven days, sections of mice kidney were taken, the organ coefficient of both kidney and brain was counted, and the reactive oxygen species (ROS) level, glutathione (GSH) and malondialdehyde (MDA) content was measured. Our results showed that in the experimental groups, the organ coefficient and GSH content in mice kidneys and brains decreased, whereas the ROS level and MDA content increased, when compared with the control. The graphene oxide group was statistically significant (p < 0.05), while the SWCNTs group had extremely significant difference (p < 0.01). Morphological changes in the kidney were also seen in the experimental groups. These results demonstrate that oxidative damage to mice kidneys and brains induced by SWCNTs and graphene oxide is more severe than graphene. The degree of damage caused by these three typical nanomaterials is different, probably due to several parameters including particle size, surface character, and shape.

It is one of the common tasks of machine vision defect detection to judge whether the resistance of PCB board is correct or not. The traditional detection method is to use the color industrial camera to take pictures, then transform the image from the RGB color model to the HSI / HSV color model, according to different colors in the new color space have different characteristics to split it out. However, this method can not meet the requirements of industrial which asked to detect a variety of defects in one workplace, and the segmentation threshold is difficult to set due to the resistance's mirror reflection. Therefore, this paper presents a new color ring recognition method which use Retinex algorithm and BP neural network classifier to distinguish color rings and use the image took by black and white industrial camera. Experiments show that the method has high accuracy and can meet the requirements of industrial defect detection.

In this paper, the air conditioning room temperature model is established and the temperature control system based on the model is designed. What's more, the fuzzy control system of air conditioning room temperature is obtained. Finally, the effect of PID controller and fuzzy controller is compared by simulation. The simulation results show that the fuzzy control system designed in this paper can realize the continuous control, reduce the indoor temperature fluctuation, and increase the comfort of air conditioning room.

Additional file 1. Additional information.

In this experiment, the oxidative damage of nano-CdSeS in mice brains was performed. 20 male Kunming mice were divided into 4 groups and 3 experimental groups were exposed to different doses of nano-CdSeS (0.1 mg/mL, 0.2 mg/mL and 0.4 mg/mL) by intravenous administration while the control used saline solution instead. Three days later, the enzymatic activity of superoxide dismutase (SOD), the content of malondialdehyde (MDA) and the damage degree of DNA were determined to assess the oxidative damage in brain tissues. Our results showed that in the experimental groups, SOD activity was inhibited and MDA content was increased as the doses rising, at the same time, tail moment and tail DNA% increased significantly when comparing with the control. And these results exhibited a certain doses-dependency relations. From results above, it demonstrated that oxidative damage of brain induced by nano-CdSeS which enter into blood–brain barrier in mice.

This paper presents a measurement design of speed torque of micro harmonic drive. On the basis of micro harmonic drive theory and the measuring method of speed torque of traditional gear an experimental system for measuring is put forward. Experimental equipment is determined. Instruments for measuring speed torque of traditional reducer can not be applied directly due to the minimal scale of micro harmonic drive. Measurement methods of micro harmonic drive and appropriate equipment are particularly important to be researched.

OMMT was compounded by MMT and 1% (v/v) acetic acid dissolved chitosan via solution intercalate method, and then prepared the composites with epoxy resin. The change about spacing of montmorillonite was tested by XRD, and the molecular structure of OMMT was tested by Fourier infrared spectrum. The tensile strength and impact strength of epoxy resin composites were also tested. The result showed that the spacing of montmorillonite first increased then decreased along with the increasing mass fraction of chitosan. The maximum value (d001=1.983 nm) appeared when mass fraction of chitosan was 30%. And tensile strength and impact strength were improved by 86.8 and 51.2% respectively.

The fly ash with a loose and porous structure has definite absorbent ability, which has a good effect on soil improvement. Illite belongs to clay minerals, it has absorbent ability and higher potassium, which can improve the soil fertility. In this study, poly(acrylic acid sodium-co-acrylamide)(PAANa-AM)/fly ash-illite superabsorbent composite was firstly prepared by solution polymerization. The structures were characterized using scanning electron microscope, X-ray diffraction, and infrared spectrum. The results showed that the fly ash and illite dispersed well in the composite. The K+ in illite was replaced by Na+ in acrylic acid sodium and thus the illite structure turned into paragonite during the process of preparing composite, however, the structure of fly ash was maintained in the composite. Moreover, the hydroxide radical in illite reacted with the carbonyl group in acrylic acid during polymerization. The best absorbent capacities of the composite in distilled water, tap water and normal saline were 1695, 445 and 106 g/g, respectively, which exceeded the requirements of The National 863 Program and Ministry of Agriculture of People’s Republic of China. The potassium release was measured using atomic absorption spectrometry and the results indicated that the composite can release 12.80% of the potassium ion in fly ash and illite. The superabsorbent material has low cost and favors improvement of soil and potassium-deficiency.

The modified attapulgite / natural rubber composites (MANRC), attapulgite / natural rubber composites (ANRC) and carbon black N330 / natural rubber composites (CBNRC) were prepared by co-coagulating rubber latex and clay aqueous suspension,respectively. The modified attapulgite was attained by dispersion with an ultrasonic cell pulverizer first and then modification with cetyltrimethylammonium bromide (CTAB). The micrographs of field emission scanning electron microscope (FESEM) and environmental scanning electron microscope (ESEM) showed that the CTAB-modified attapulgite have the best dispersibility in the composites. The mechanical properties of MANRC are the best. The best properties of MANRC can be obtained when 20phrCTAB-modified attapulgite was added, the tensile strength, the 200% tensile modulus, the tear strength and Shore A hardness increased by 58.2%, 109.3%, 46.0%, 27.8%, respectively, compared with CBNRC.

Epoxy resin/ montmorillonite (EP/MMT) composite was prepared via monomer insert in-situ polymerization. It was shown that the EP/MMT composites could be successfully synthesized from the raw materials only by one step, making it simpler than traditional in-situ intercalative polymerization method. The d001 spacing of montmorillonite was tested by XRD and increased to 4.30nm. The results showed that tensile strength and impact strength were improved by 98.11 and 93.69%, respectively. The glass transition temperature was increased by 17.3 °C.

The melamine phosphate (MP) was synthesized from melamine and phosphate acid. Zinc oxide (ZnO) was used as a synergistic agent by adding into the MP during the synthesis process. The reaction products were characterized by Fourier transform infrared spectroscopy (FTIR). The properties of polypropylene (PP) composites containing intumescent flame retardant (IFR) additives of melamine phosphate and pentaerythritol (PER) were investigated by the limiting oxygen index (LOI), UL-94 vertical burning test, thermogravimetric analysis (TG) and scanning electron microscopy (SEM). The results indicated that the LOI value of the composites could be enhanced obviously with suitable content of ZnO. When the ZnO content was 6 wt% in MP, the LOI value reached 34.1%, which showed 10% higher than that of the composites without ZnO.

The attapulgite / natural rubber (NR) micro-nano composites were prepared by co-coagulating rubber latex and clay aqueous suspension. The vulcanization behavior, mechanical properties and microcosmic structure of the composites were investigated. The field emission scanning electron microscope (FESEM) micrographs of the composites showed that the attapulgite stick particles inserted into the rubber. The interaction between the attapulgite and natural rubber could be improved by using the attapulgite pre-modified with cetyltrimethylammonium bromide (CTAB). The properties of the composites filled with CTAB-modified attapulgite are better than that of the composites filled with carbon black N330. The best properties, which the tensile strength, the 300% tensile modulus and the tear strength increase by 46.9%, 269.7%, 102.0%, respectively, compared with the composites with the unmodified attapulgite, can be obtained, when 20 phr CTAB-modified attapulgite was added.

The graphite-modified PZN-PZT/PVDF composites were fabricated by hot-pressed process using PZN-PZT ceramic powder, PVDF and graphite powder. The effect of graphite content on the electrical properties of the piezoelectric composites was investigated. The results indicated that the piezoelectric constant d33 could be enhanced obviously by adding suitable content of graphite into the composites. When 0.8wt% graphite was added, the PZN-PZT/PVDF composites showed the excellent properties: σ=3.31×10-6S/m, εr=133, tanδ=0.066, Kp=0.228, Qm=22.8 and d33=40.6pC/N, which showed 28% higher than that of the composites without graphite.

Effect of acute toxicity and chronic toxicity on attapulgite for animal was studied by Kunming mice and SD rats experiment through administering intragastrically with large dose of attapulgite suspension. The results showed that the mice were normal and grew well, and they did not appear death and toxicity symptoms when they received the same amount as 286 times of the adult dose, indicating that attapulgite mineral powders did not contain acute toxicity and administering intragastrically with large dose of attapulgite suspension had no obvious influence on blood environment and normal growth of rats, and attapulgite did not contain chronic toxicity.

Using a method of physically adsorbing and chemically coordinating cobalt porphyrin on to boehmite, a new boehmite-supported cobalt tetraphenylporphyrin [Co II TPP/BM] catalyst has been prepared and characterized by UV–Vis, FT-IR, XRD, TEM and TG techniques. The supported catalyst was used for aerobic oxidation of cyclohexane under mild conditions and in the absence of any solvent and additive. The experimental results indicate that, after 10 consecutive uses for the oxidation, a quantity of catalyst containing only 1 mg of cobalt porphyrin, can not only provide, on average, 9.2% cyclohexane conversion, 92.1% selectivity for K/A oil and a catalyst turnover number of 1.14 × 10 5 , but also can maintain continuously the original catalytic activity with promotion by beomite (BM). A proposed reason for the good reusability and stability of the supported catalyst for aerobic oxidation of cyclohexane was that the anchored form of the single cobalt porphyrin molecules were highly dispersed and immobilized on the boehmite.

The search for a reusable material as an efficient and economic catalyst for hydrocarbon oxidation is an important field of research. In this study, we investigated the highly effective combination of support and metalloporphyrin provided by manganese tetraphenylporphyrin adsorbed onto a precursor of freshly precipitated aluminium hydroxide, followed by conversion to a manganese porphyrin/boehmite compound. This was characterized using FT-IR, UV–vis spectroscopic techniques, N 2 BET analysis, X-ray powder diffraction, transmission electron micrograph technique and thermal analysis. Aerobic oxidation of cyclohexane has been investigated using the compound as a catalyst under mild conditions and in the absence of any solvent and reductant. The results indicate that it has higher catalytic activity than manganese tetraphenylporphyrin and the corresponding chitosan-supported catalyst. In particular, the catalyst exhibits good atom economy for cyclohexane oxidation, high catalyst turnover number, and good ketone and alcohol selectivity. In particular, it has excellent reusability, with no change in original catalytic activity; a quantity of catalyst containing only 1 mg of Mn TPP can be reused 8 times under the promotion of beomite (BM). In addition, we examined the reaction conditions for the use of such nanoparticle-supported manganese tetraphenylporphyrin as a mild and environmental friendly oxidation catalyst.

KNbO 3 films were prepared on Si (100) substrates by pulsed laser deposition. The effect of experimental parameters on the films structure and composition was investigated. Well crystallized and single-phase KNbO 3 films were obtained at the substrate temperature of 650 °C, laser energy of 7.5 mJ/pulse and target-substrate distance of 40 mm, but a severe potassium-deficient was observed in the deposited films. The mechanism of K deficiency in films was explored and a method to control the composition was designed. The experimental results indicate that the composition of films can be well controlled by adjusting the oblique angle of substrates from the axial direction of plume. The stoichiometric KNbO 3 films with K/Nb molar ratio of 0.98 were obtained by locating the substrate at an oblique angle of 3–12° from the plume axis.

The highly selective catalytic oxidation of toluene with air to benzaldehyde and benzyl alcohol in the liquid phase has been studied with the use of iron tetraphenylporphyrin (Fe TPP) supported on chitosan (CTS), (Fe TPP/CTS). The rates of toluene conversion and selectivity (aldehyde + alcohol) were subject to the reaction temperature, air pressure, and amount of iron tetraphenylporphyrin. By the use of the Fe TPP/CTS, containing 2 mg of iron tetraphenylporphyrin as catalyst, toluene oxidation with air under the optimum conditions of 190 °C and 0.6 MPa produced benzaldehyde and benzyl alcohol at 90% selectivity and 5.4% conversion of toluene, the mole turnover of the catalyst was about 6 × 106, and it could be reused efficiently for one more time. It is suggested that the amine groups (–NH2) on the chitosan chain act as a key assistor to the catalysis of Fe TPP for toluene oxidation. Compared with the conventional method of synthesizing benzaldehyde and benzyl alcohol, the new method has the advantages of reduced environmental pollution, higher selectivity for the two main products, and easy recovery of the catalyst.Key words: chitosan-supported iron porphyrin, catalysis, toluene oxidation, benzaldehyde, benzyl alcohol.

Manganese tetraphenylporphyrin (Mn TPP) has been successfully supported on chitosan (CTS), chitin (CTN) and cellulose (CLS) by means of physical adsorption, and they are characterized by UV–Vis spectroscopy. The supported catalysts exhibit enhanced activity and effective recycle (except for Mn TPP/CLS) for oxidation of cyclohexane in the presence of air as oxidant. Both Mn TPP/CTS and Mn TPP/CTN show higher selectivity for cyclohexanone and cyclohexanol, whereas Mn TPP/CLS shows lower selectivity. The kind of support influences the catalytic activities and the selectivity for the supported catalysts. Appearance of the catalytic differences is attributed to the presence of the microenvironment differences for the supports.

The chitosan-supported μ-oxo dimeric iron tetraphenylporphyrin ((TPPFeIII)2O/CTS) was prepared and its ability to catalyze aerobic oxidation of cyclohexane into the corresponding ketone and alcohol in the absence of any co-reductants and solvents was investigated. Under the optimum reaction conditions of 398 K and 0.6 MPa, the heterogeneous catalytic system gave about 90% selectivity of ketone and alcohol at 13.0% yield and a catalyst turnover number of 1.03 × 105. The supported catalyst can be efficiently reused at least six times. The changes in various catalytic parameters with reaction temperature, pressure and the amount of catalyst were investigated. Compared with the corresponding unsupported catalyst, (TPPFeIII)2O/CTS was more robust towards destruction by oxygen and provided better catalysis for cyclohexane oxidation.

The composition of KNbO 3 thin films prepared by pulsed laser deposition is crucially influenced by the deposition configuration. In the present study, the composition of KNbO 3 thin films grown on Si (100) substrates by pulsed laser ablation was tried to be controlled by adjusting the target–substrate distance and the oblique angle of substrate from the plume axial direction. It was found that the K deficiency in the films can be effectively avoided by setting the substrate at an appropriate oblique angle from the plume axial direction. The stoichiometric KNbO 3 thin films with a K/Nb molar ratio of 0.98 were successfully obtained, where the substrates were set at an oblique angle of 3–12° from the plume axis while the target–substrate distance was kept at 40 mm.

Empirical mode decomposition(EMD) has been proved that it is an extraordinary useful nonparametric signal denoising, which adaptively breaks down any signal into oscillatory components called intrinsic mode functions(IMFs). For EMD-based denoising, how to select relevant extracted modes and how to select threshold for denoising are two main questions to resolve urgently. This paper introduces a new EMD-based denoising, tremed EMD-corIT, which combines an estimation of correlation coefficient and the EMD interval thresholding denoising (EMD-IT). The selection of relevant modes is dependent on the correlation coefficient between the IMFs and the original signal. Numerical simulation test were carried out to evaluate the effectiveness of this method. Other traditional EMD denoising, such as correlation-based EMD partial reconstruction, EMD direct thresholding (EMD-DT) are also investigated in this paper to provide a comparison. Simulation results show its superior performance over other traditional EMD denoisings in whole.

Geochemical characteristics of the Upper Permian (P2) continental marginal arc volcanic rocks are described, which have been found recently around the areas of Xiaodingxi and Zangli on the eastern side of the Yunxian-Lincang granite, in terms of rock assemblage, petrochemistry, REE, trace elements, Pb isotopes, geotectonic environment and so on. The volcanic rock assemblage is dominated by basalt-andesite-dacite, with minor trachyte andecite-trachyte; the volcanic rock series is predominated by the calc-alkaline series, with minor tholleiite series and alkaline series rocks ; the volcanic rocks are characterized by high A12O3 and low TiO2, with K2O contents showing extremely strong polarity; the REE distribution patterns are characterized by LREE enrichment and right-inclined type; trace elements and large cation elements are highly enriched, Ti and Cr are depleted, and P and Nb are partially depleted; the Pb composition is of the Gondwana type; the petrochemical points mostly fall within the field of island-arc volcanic rocks, in consistency with the projection of data points of continental marginal volcanic rocks in the southern segment of the South Lancangjiang Belt and the North Lancangjiang Belt. This continental marginal arc volcanic rock belt, together with the ocean-ridge and ocean-island volcanic rocks and ophiolites in the Changning-Menglian Belt, constitute the ocean-ridge volcanic rock, ophiolite-arc rock-magmatic rock belts which are distributed in pairs, indicating that the Lancangjiang oceanic crust subducted eastwards. This result is of great importance in constraining the evolution of the paleo-Tethys in the Lancangjiang Belt.

The basic technology and properties of the brake blocks made of modified needle-like wollastonite and fibrous sepiolite were intensively researched. The impact strengthes and fixed velocity friction of the brake blocks prepared by different recipes were tested. The testing results show that it is feasible for needle-like wollastonite and fibrous sepiolite to take the place of asbestos as the reinforced materials of friction materials. The braking effect of the brake blocks is the best when the ratio of the needle-like wollastonite to the fibrous sepiolite was 1∶6.