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Biomass-derived 2,5-dimethylfuran (DMF) is an ideal, renewable gasoline additive, and its production with high productivity is highly desirable. A continuous production route was developed to yield...

In this paper, we study the production of aromatic hydrocarbons by co-feeding furans and methanol in a continuous flow fixed-bed reactor over HZSM-5 at 400–600 °C. The effects of reaction temperature, weight hourly space velocity (WHSV), furan to methanol molar ratio and time on stream on the product distribution were investigated. Maximum aromatics yield of 42.0% was obtained over HZSM-5 (Si/Al = 25) with 2-methylfuran (MF) to methanol molar ratio of 1:5 at 500 °C. With the methanol to MF molar ratio increasing from 0 to 5, the conversion of MF increased from 64.7% to 100.0% and the yield of coke decreased from 22.3% to 11.4%. In this process, dimethyl ether derived from methanol dehydration could promote the conversion of MF to aromatic hydrocarbons via Diels-Alder reaction. HZSM-5 with Si/Al ratio of 25 exhibited superior catalytic activity, indicating that strong acidity was necessary for the coupling conversion of MF and methanol. Additionally, the coupling conversions of 2,5-dimethylfuran (DMF), furfural (FF) and furfuryl alcohol (FA) and methanol were investigated. Functional groups of furan rings did not change the formation pathway of aromatic hydrocarbons but they have different constraints on the Diels-Alder reaction of furan ring with olefins.

In the present study, a novel route of upgrading lignin pyrolysis vapor to aromatic hydrocarbons was investigated. Guaiacol was used as model compound to investigate the coupling conversion of pyrolysis vapor and methanol. Co-feeding methanol obviously facilitated the conversion of guaiacol to aromatic hydrocarbons and inhibited coke formation. HZSM-5, Al-MCM-41 and γ-Al2O3 catalysts were screened, and γ-Al2O3 showed the best catalytic activity for the catalytic co-cracking reaction due to the appropriate acid property. The effects of methanol to guaiacol molar ratio, reaction temperature and W/Fguaiacol on product distribution over γ-Al2O3 were studied in a fixed bed reactor to reveal the reaction mechanism. As hydrogen donor, the co-fed methanol promoted the deoxygenation of guaiacol. The water formed through methanol dehydration was an efficient agent for attenuating coke deposition. The highest yield of aromatic hydrocarbons was 81.2% when the methanol to guaiacol molar ratio was 25 at 400 °C. The investigation of W/Fguaiacol indicated that the synergistic effect of co-feeding was sensitive at lower W/Fguaiacol. Co-feeding methanol with phenol, anisole and the phenolic mixture were also investigated, and high yields of aromatic hydrocarbons were obtained, which demonstrated that co-feeding methanol was a promising process for upgrading complicated pyrolysis products.

To determine host-related infochemicals that facilitate contact between the egg-pupal parasitoid, Fopius arisanus (Sonan), and its host, Bactrocera dorsalis (Hendel), we analyzed the volatiles on the surface of B. dorsalis eggs by hydrocarbon profiling of the hexane extracts using Gas Chromatography–Mass Spectrometry (GC–MS). These analyses resulted in the identification of 12 components from the egg surface. Among these 6 were alkanes (Dodecane, Heneicosane, Docosane, Tricosane, Tetracosane and Pentacosane) and the proportion was 42.79%, 1 was a fatty acid (Palmitic acid) and the proportion was 3.88%, 3 were fatty acid derivatives (Dodecanoic acid methylester, Lauric acid ethyl ester and Ethyl tetradecanoate) and the proportion was 45.92%, and 2 were alcohols (Tetradecanol and Hexadecanol) and the proportion was 7.41%. 9 chemicals were chosen from the above 12 components to study the EAG and behavioral responses of male and female F. arisanus. The results showed that the EAG and behavioral responses of F. arisanus to same chemical had similar trends, and both EAG relative values and lure rates of females were higher than males' generally. However, for Dodecane and Tetracosane the EAG relative values and lure rates showed extremely significant differences between males and females respectively, for Tricosane there was significant difference, for Ethyl tetradecanoate there was no significant difference between males and females of the relative EAG values but of the lure rates there was significant difference. The results maybe provide new insights from the chemical relationship between parasitoid and host to biocontrol B. dorsalis using F. arisanus.

We aim to analyze the feasibility of external application of Xiao-Shuan-Santo prevent peripherally inserted central catheter (PICC) -related thrombosis.A total of 218 patients with PICC catheterization were randomly divided into a control group (n = 103) and a treatment group (n = 115). Patients in the treatment group received additional external application of Xiao-Shuan-San. The changes of coagulation index, the incidence of PICC-related thrombosis and other complications, and the maximum blood flow rate (Vmax) of axillary vein were observed at 1 day before catheterization and 30 days after PICC.At 30 days after PICC, the incidence of PICC-related thrombosis and other adverse events in the treatment group were obviously lower than that in the control group (P 0.05), and the decreased Vmax value of axillary vein in the control group (11.75±1.91 cm/s) was more visible than that in the treatment group (14.63±3.03 cm/s), accompanied by a statistical significance (P 0.05).External application of Xiao-Shuan-San could reduce the incidence of PICC-related thrombosis and other complications.

Layered double hydroxide (LDH) is a layered solid containing positively charged layers with negatively charged anions as an interchangeable interlayer. In this research, Mg(Al)O supports were synthesized with three different Mg:Al molar ratios, and bimetallic PtSn catalysts were loaded onto the supports via the anion exchange method. The properties of ethane dehydrogenation of the PtSn/Mg(Al)O catalysts were investigated. The results show that the structure and properties of the PtSn/Mg(Al)O catalysts were influenced by the Mg:Al molar ratio of the hydrotalcites, which consequently influenced the ethane dehydrogenation performance. When the Mg:Al ratio was 5:1, the ethane dehydrogenation performance was optimal, relative to the Mg:Al ratios of 2:1 and 10:1.

Calcium carbonate whisker is a new kind of environmental-friendly inorganic material. Some advantages of calcium carbonate whisker such as low manufacture cost, simple preparation condition and excellent properties draw a lot of attention and make it higher potential competitive in the market. This review summarizes the research progress of calcium carbonate whiskers prepared with the different methods such as carbonation method, metathesis reaction method, sol-gel method, urea hydrolysis method and gravity crystallization method, and describes the research status in diverse applications of calcium carbonate whisker in enforcement of composite materials, being as filler of paper-making and additives in friction materials.

Acute carbon monoxide (CO) poisoning is the most common cause of death from poisoning all over the world and may result in neuropathologic and neurophysiologic changes. Acute brain damage and delayed encephalopathy are the most serious complication, yet their pathogenesis is poorly understood. The present study aimed to evaluate the neuroprotective effects of Edaravone against apoptosis and oxidative stress after acute CO poisoning. The rat model of CO poisoning was established in a hyperbaric oxygen chamber by exposed to CO. Ultrastructure changes were observed by transmission electron microscopy (TEM). TUNEL stain was used to assess apoptosis. Immunohistochemistry and immunofluorescence double stain were used to evaluate the expression levels of heme oxygenase-1 (HO-1) and nuclear factor erythroid 2-related factor 2 (Nrf-2) protein and their relationship. By dynamically monitored the carboxyhemoglobin (HbCO) level in blood, we successfully established rat model of severe CO poisoning. Ultrastructure changes, including chromatin condensation, cytoplasm dissolution, vacuoles formation, nucleus membrane and cell organelles decomposition, could be observed after CO poisoning. Edaravone could improve the ultrastructure damage. CO poisoning could induce apoptosis. Apoptotic cells were widely distributed in cortex, striatum and hippocampus. Edaravone treatment attenuated neuronal apoptosis as compared with the poisoning group (P

Phosphogypsum is a kind of by-product of the phosphate fertilizer production process, mostly in the form of CaSO4·2H2O, the analytical determination of the content of the main component is the basis for the comprehensive utilization of phosphogypsum. This paper introduces three analytic procedure to determinate the content of crystal water, SO42-, Ca2+ to calculate the CaSO4 content of phosphogypsum, through a comparison between the results of three methods, we can conclude that granularity of phosphogypsum has the smallest influence on the crystal water determination method, but only applicable to determination of gypsum containing crystal water in single phase. However, the measure of SO42-, Ca2+ is not restricted by the phosphogypsum phase, but influenced by the particle size. SO42- determination operation is relatively simple and easy to control, reversely, Ca2+ determination operation is complex and hard to control.

The application of high purity phosphoric acid in industrial production is more and more widely used, especially electronic grade phosphoric acid, and the demand of it has risen year by year. This paper introduces the preparation and research advance of electronic grade phosphoric acid, expounds the principle, advantages and disadvantages and research advance of preparing high purity phosphoric acid by high purity phosphorus oxidation method and phosphoric acid purification method. Using hot process by direct method to prepare high purity electronic grade phosphoric acid is still the mainstream on the current, and the key of technique is the purification of yellow phosphorus and phosphoric acid.

This paper takes the conversion system of sulphuric acid plant made with the sulphur as research object, utilizes Aspen Plus process simulation software to carry out steady state process simulate for the conversion process, and obtains physical property data of all the process streams; utilizing Aspen Energy Analyzer software, that the minimum heat transfer temperature difference (ΔTmin) determined is 10 °C, the temperature-enthalpy composite curve and the pinch temperatures of hot and cold streams are got under the ΔTmin, the energy consumption of heating utilities reaches zero, and cooling utilities use 45 °C of desalted water. Simulating for heat exchange network with pinch technology and Simulating the matching design of heat exchange network with Aspen Energy Analyzer software, the heat exchange effect is basically as same as the heat exchange network in actual production.

This paper takes the conversion system of sulphuric acid plant made with the sulphur as research object, utilizes Aspen Plus process simulation software to carry out steady state process simulate for the conversion process, and obtains physical property data of all the process streams; utilizing Aspen Energy Analyzer software, that the minimum heat transfer temperature difference (ΔTmin) determined is 10 °C, the temperature-enthalpy composite curve and the pinch temperatures of hot and cold streams are got under the ΔTmin, the energy consumption of heating utilities reaches zero, and cooling utilities use 45 °C of desalted water. Simulating for heat exchange network with pinch technology and Simulating the matching design of heat exchange network with Aspen Energy Analyzer software, the heat exchange effect is basically as same as the heat exchange network in actual production.

The phosphogypsum is a byproduct of the phosphorus chemical industry, which has not high utilization ratio, is the main area of stockpiling and affects the environment and the sustainable development of phosphorus chemical enterprises. Based on the sulfur resources utilization status from the existing phosphogypsum in the article, the use patterns on the phosphogypsum are divided into three types of hot, wet and biological methods, and there are the reviews on the utilization status of the various methods.

This article took the sodium sulfate and calcium chloride as the raw material and prepared calcium sulfate whiskers by hydrothermal method. The experimental results show that the calcium sulfate precursors are prepared by the reverse feed mode in which the sodium sulfate solution drop into the calcium chloride solution under the solution concentration 0.6 mol/L and the molar ratio of Na2SO4 to CaCl2 at 1:1.8. The precursors were placed in pH=6.12 hydrothermal environments and treated in the autoclave at 140 °C for 4 h to obtain the calcium sulfate whiskers having for the ratio of length to diameter at 97.5 and the better morphology.

The possibility of decomposition of cefotaxime sodium wastewater by ultrasonic Fenton method was discussed in this paper. The influence of various experimental parameters on the decomposition of the wastewater was investigated. The experiment results showed that 44.1% of COD can be removed and the value of BOD5/COD increased up to 0.99, revealing that the combined ultrasonic Fenton technology is an effectively method to treat the cefotaxime sodium wastewater.

Understanding the mechanisms of host–pathogen interaction can provide crucial information for successfully manipulating their relationships. Because of its genetic background and practical advantages over vertebrate model systems, the nematode Caenorhabditis elegans model has become an attractive host for studying microbial pathogenesis. Here we report a “Trojan horse” mechanism of bacterial pathogenesis against nematodes. We show that the bacterium Bacillus nematocida B16 lures nematodes by emitting potent volatile organic compounds that are much more attractive to worms than those from ordinary dietary bacteria. Seventeen B. nematocida -attractant volatile organic compounds are identified, and seven are individually confirmed to lure nematodes. Once the bacteria enter the intestine of nematodes, they secrete two proteases with broad substrate ranges but preferentially target essential intestinal proteins, leading to nematode death. This Trojan horse pattern of bacterium–nematode interaction enriches our understanding of microbial pathogenesis.

Acute carbon monoxide (CO) poisoning is the most common cause of death from poisoning all over the world and may result in neuropathologic and neurophysiologic changes. Acute brain damage and delayed encephalopathy are the most serious complication, yet their pathogenesis is poorly understood. The present study aimed to evaluate the neuroprotective effects of Edaravone against apoptosis and oxidative stress after acute CO poisoning. The rat model of CO poisoning was established in a hyperbaric oxygen chamber by exposed to CO. Ultrastructure changes were observed by transmission electron microscopy (TEM). TUNEL stain was used to assess apoptosis. Immunohistochemistry and immunofluorescence double stain were used to evaluate the expression levels of heme oxygenase-1 (HO-1) and nuclear factor erythroid 2-related factor 2 (Nrf-2) protein and their relationship. By dynamically monitored the carboxyhemoglobin (HbCO) level in blood, we successfully established rat model of severe CO poisoning. Ultrastructure changes, including chromatin condensation, cytoplasm dissolution, vacuoles formation, nucleus membrane and cell organelles decomposition, could be observed after CO poisoning. Edaravone could improve the ultrastructure damage. CO poisoning could induce apoptosis. Apoptotic cells were widely distributed in cortex, striatum and hippocampus. Edaravone treatment attenuated neuronal apoptosis as compared with the poisoning group (P 0.01). Basal expressions of HO-1 and Nrf-2 proteins were found in normal brain tissue. CO poisoning could activate HO-1/Nrf-2 pathway, start oxidative stress response. After the administration of Edaravone, the expression of HO-1 and Nrf-2 significantly increased (P 0.01). These findings suggest that Edaravone may inhibit apoptosis, activate the Keapl-Nrf/ARE pathway, and thus improve the ultrastructure damage and neurophysiologic changes following acute CO poisoning.

Two novel thermophilic, spore-forming bacterial strains, T-11T and E-112T, were isolated from hot springs in Tengchong and Eryuan counties of Yunnan province in south-west China. The strains were Gram-stain-positive rods, occurring singly or in chains. Growth of strain T-11T was observed between 30 and 75 °C (optimum 50 °C) and at pH 7–11 (optimum pH 8.5), while the temperature range for strain E-112T was 35–70 °C (optimum 55 °C) and the pH range was 7.0–11.0 (optimum pH 8.0). The DNA G+C contents of strains T-11T and E-112T were 41.1 and 42.6 mol%, respectively. On the basis of 16S rRNA gene sequence similarity, the two strains were shown to be related most closely to Anoxybacillus species. The chemotaxonomic characteristics [predominant isoprenoid quinone menaquinone 7 (MK-7); major fatty acids iso-C15 : 0 and iso-C17 : 0] also supported the affiliation of strains T-11T and E-112T to the genus Anoxybacillus. The results of DNA–DNA hybridization and physiological and biochemical tests allowed genotypic and phenotypic differentiation of strains T-11T and E-112T from Anoxybacillus species with validly published names. Strains T-11T and E-112T therefore represent two novel species, for which the names Anoxybacillus tengchongensis sp. nov. (type strain T-11T =CCTCC AB209237T =KCTC 13721T) and Anoxybacillus eryuanensis sp. nov. (type strain E-112T =CCTCC AB209236T =KCTC 13720T) are proposed.