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Nowadays, the environmental problems caused by the burning of fossil fuels as vehicle fuel have become more and more serious in the world. Many countries are carrying out the research on the alternative energy sources and the clean energy. Meanwhile, China has begun to focus on the development of the gas mixture containing hydrogen as the vehicle fuel, mainly hydrogen enriched compressed natural gas (HCNG) and coke oven gas (COG). Application status of HCNG and COG as the vehicle fuel in China were reviewed and their existing problems were analyzed. The analysis results shows that the relevant regulations standards of HCNG vehicle, COG vehicle and their refueling stations have not been formulated and unified yet and the optimal hydrogen ratio of the HCNG requires further experimental investigation and theoretical analysis. In addition, as a country with substantial COG wasted, China can make better use of the wasted hydrogen contained in COG to realize the miniaturization and closed production of the COG without pollution. HCNG and COG as vehicle fuel are beneficial for the development of the hydrogen energy, which can alleviate the crisis of global energy shortage and effectively reduce the production and emission of sulfur oxides. Therefore, the prospects of HCNG and COG as the vehicle fuel are good in China.

Arachidonic acid (ARA) is involved in the growth and regulation of immunity in fish. Little research has focused on ARA in crustaceans. This study was an 8-week feeding experiment investigating the effects of dietary ARA on growth, antioxidative indices, and immune characteristics of the juvenile oriental river prawn (Macrobrachium nipponense). An ARA-enriched oil was supplemented into the basal diet to formulate six isonitrogenous and isoenergetic diets containing 0.02% (the control group), 0.28%, 0.54%, 0.86%, 1.22%, and 1.54% ARA dry weight. Diets were fed to juvenile prawns (mean weight: 0.104 ± 0.002 g) twice daily to apparent satiation in three replicates. Weight gain and specific growth rate of M. nipponense significantly increased with increasing dietary levels of ARA from 0.02% to 0.86% and thereafter declined. Hepatopancreas super oxide dismutase and catalase activities significantly increased with supplementation with ARA, particularly in prawns fed 1.22% and 1.54% ARA. The malondialdehyde level in prawns fed 1.54% ARA also significantly increased, and was higher than that of prawns fed ARA from 0.02% to 0.86%. Serum lysozyme activity was significantly greater in prawns fed 0.86% ARA compared with the other groups. mRNA expression of toll-like receptor signaling pathway-related genes was promoted by a dietary ARA level from 0.54% to 0.86% but inhibited with the higher ARA levels (1.22–1.54%). The mortality percentage increased after challenge with live Aeromonas hydrophila. The mortality percentage of prawns fed 1.54% ARA was significantly higher than that of prawns fed 0.28–1.22% ARA. The results suggest that the optimal dietary ARA requirement for juvenile M. nipponense is 0.82% (dry weight) based on second-order regression analysis of weight gain vs. dietary ARA level, and that 0.86% ARA could significantly enhance non-specific immunity of M. nipponense; however, too high a level of ARA will affect the health status of this prawn.

AB38b is a novel biphenyl diester derivative synthesized in our laboratory, and it has been shown to improve the pathology of nephropathy and encephalopathy in diabetic mice. Glioblastoma (GBM) is the most lethal brain tumor, without effective drugs to date. The present study aims at investigating the role of AB38b in GBM growth and revealing the underlying molecular mechanisms. We found that AB38b administration showed a dose- and time-dependent inhibition on cell proliferation in multiple immortalized and primary GBM cell lines, but it had no significant effects on human astrocyte cell line. More importantly, AB38b blocked cell cycle progression, induced early apoptosis, decreased the activity of AKT/mTOR pathway, and increased the generation of reactive oxygen species (ROS) in GBM cells. Interestingly, antioxidant treatments could reverse the AB38b-mediated abovementioned effects; overexpression of constitutively active AKT could partially rescue the suppressive effects of Ab38b on GBM cell proliferation. In addition, AB38b administration inhibited the tumor growth, decreased the activity of AKT/mTOR pathway, and prolonged the survival time in GBM animal models, without any adverse influences on the important organs. These findings suggest that AB38b exerts anti-glioma activity via elevating the ROS generation followed by inhibiting the activity of AKT/mTOR pathway.

The viscoelastic materials exhibit different tribological responses when compared to the stiff materials, due to the intermediate mechanical properties between viscous liquid and elastic solid. In this work, the effect of damping materials viscoelasticity on sliding friction under dry condition was investigated. However, it was difficult to change its damping properties only while other properties (strength or surface hardness) remain unchanged, since viscoelasticity was one of its intrinsic properties. Therefore, the attention of interactions between the material components was closely paid. To achieve this, the experimental groups of damping materials with various viscoelasticity were established by adding various fillers and adjusting their surface properties. Additionally, a viscoelastic property determined friction coefficient model was obtained and validated by the molecular dynamic method. The results show that the test model is in good agreement with the experimental results. Meanwhile, tribo-pairs with higher proportion of viscous character had greater oscillations in friction. They also exhibited higher friction coefficient due to the increased contribution of viscoelastic hysteresis losses to friction.

The shearing performance and strength of the interface between rock foundations and structural concrete is a key issue for safety estimation in geotechnical engineering containing rock-concrete interface. In this paper, we focused on the effects of concrete wall strength and normal stress on the unbonding performances of sandstone-concrete interface. First, many sandstone-concrete specimens containing a natural dam bedrock interface had been produced by using “3D optical scanning technology + 3D digital engraving technology + pouring concrete” method. Subsequently, after the sandstone-concrete specimens were prepared, a series of shear tests for these sandstone-concrete specimens were carried out under different normal loading conditions. Finally, the shear characteristics of sandstone-concrete interface were discussed, and an improved rock-concrete shear strength formula was proposed based on the exposed experimental tests and theoretical derivation. Three primary outcomes are as follows: (i) shear damage only occurred at some special positions of the concrete wall, and its degree of shear damage gradually increased with increasing normal stress; (ii) the damage degree of the concrete surface performed obvious localization and nonuniformity was affected by the concrete strength; (iii) the global shear strength and residual strength of the rock-concrete interface were affected by the concrete strength and the normal load. Moreover, an improved rock-concrete shear strength formula was proposed based on the experimental cognition. This strength formula considers both the interface roughness and the mechanical strength of rock/concrete materials, and is more reasonable for estimating the shear strength of rock-concrete interfaces in geotechnical engineering.

Feeding frequency is important for the improvement of growth performance and immunity of aquatic animals. In this study, the effect of feeding frequency on growth, body composition, antioxidant status and mRNA expression of immunodependent genes before or after ammonia-N stress was examined in Macrobrachium nipponense. Prawns were randomly assigned to one of five feeding frequencies (1, 2, 3, 4 and 6 times/day) following the same ration size over an 8-week growth trial. After the feeding trial, prawns were challenged by ammonia-N. The weight gain of prawns fed with 3-6 times/day was significantly higher than that of prawns fed with 1 time/day. The best feed conversion ratio was obtained from prawns fed with 3-6 times/day. Body crude lipid with feeding frequency of 3, 4 or 6 times/day was quite lower than that with 1 time/day. High feeding frequency (6 times/day) induced significantly elevated hepatopancreas super oxide dismutase and catalase activities. The malondialdehyde level in prawns fed with 6 times/day was also significantly increased, which was higher than that of prawns fed with other feeding frequency. mRNA expression of toll like receptor 3 and myeloid differentiation primary response protein MyD88 was promoted by feeding frequency from 3 to 4 time/day but inhibited by high or low feeding frequency. Similar mRNA expression variation trends of the two genes were observed in prawns after ammonia-N stress. After ammonia-N challenge, the highest cumulative mortality was observed in prawns fed with 6 times/day, which was significantly higher than that of prawns fed with 2-4 times/day. These findings demonstrate that (1) too high feeding frequency induced oxidative stress and malondialdehyde accumulation, negatively affecting the health status of prawns and reduced its resistance to ammonia-N stress; (2) the optimal feeding frequency to improve growth and immune response of this species at juvenile stage is 3-4 times/day; (3) considering costs of labour, a feeding frequency of 3 times/day is recommended for this prawn.

This paper reports the formation of styrene monomer, dimer and trimer in the primary volatiles during fast pyrolysis of polystyrene in a wire-mesh reactor where secondary reactions of primary pyrolysis volatiles are minimized. Styrene monomer is the most abundant product in the primary volatiles from polystyrene pyrolysis, with a selectivity of 48–69 wt% depending on pyrolysis temperature, while dimer and trimer only have selectivities of 8–10 and 9–30 wt%, respectively. High temperature promotes the formation of styrene monomer and suppresses the formation of styrene trimer, but with little effect on the formation of styrene dimer. It is also found that the selectivities of styrene monomer, dimer and trimer show negligible changes with increasing the conversion level at the same pyrolysis temperature. The results suggest neither 1,3-hydrogen transfer nor intermolecular benzyl radical addition is the dominant formation mechanism for styrene dimer. The styrene dimer is more likely produced via the 1,7- and 7,3-hydrogen transfer mechanism.

Nuclear facilities often produce some wastewater containing tritium, which cannot be discharged directly because of the radioactivity of the tritium. It is of great significance to study the dynamic change rules of tritium concentration during wastewater containing tritium electrolysis with SPE for tritium enrichment for the estimation of the environmental tritium concentration and the recovery of tritium resources. The dynamic equation of low tritium is established on account of the electrolytic reaction and the balance equation of hydrogen isotope exchange in gas and liquid phases. The theoretically dynamic change rules of tritium concentration are studied while continuous feeding wastewater (light water) containing tritium electrolysis and batch feeding wastewater (light water) containing tritium electrolysis, so as to lay a necessary theoretical basis for the research of recycling of wastewater containing tritium.

The cobalt alkylene polyamine complex, known as a kind of cobalt complexes, is mixed with VB and VIB compounds (in the Periodic Table VB and VIB) such as vanadium pentoxide, sodium molybdate etc. according to a certain proportion. Then it is added to alkaline electrolyte. In the process of water electrolysis, metal ions in lower overvoltage are introduced into the cathode chamber of the electrolytic cell and are plated onto the nickel-based electrode, which increases the activity of cathodic electrolysis, thereby reducing the electrolysis power consumption of cell voltage.

N-acetyl- d -neuraminic acid (Neu5Ac) has been considerably focused due to its promising potential applications in pharmaceuticals and dairy products. A whole-cell biocatalyst process is an important tool for synthesis of pharmaceutical intermediates and fine chemicals. In this study, a whole cell process using engineered Escherichia coli strain was developed and stepwise optimization was employed for Neu5Ac production. N-acetyl- D -glucosamine 2-epimerase and Neu5Ac aldolase were overexpressed in E. coli individually and the activity ratio was optimized by varying recombinant amounts of cell biomass for synthesis of Neu5Ac. Moreover, substrate concentrations and ratio of pyruvate and N-acetyl- D -glucosamine (GlcNAc) and detergent concentrations were optimized to increase product synthesis. The resulting process generated 237.4 mM Neu5Ac with a yield of 40.0% mol/mol GlcNAc. Furthermore, transporter pathways involved in Neu5Ac and GlcNAc were engineered and their impact on the Neu5Ac synthesis was evaluated. Using a stepwise optimization, an overall whole-cell biocatalytic process was developed and a maximum titer of 260.0 mM Neu5Ac (80.4 g/L) with a conversion yield of 43.3% from GlcNAc was achieved. The process can be used for industrial large-scale production of Neu5Ac in terms of efficiency and economy.

An understanding of the catalytic effect of potassium on lignin pyrolysis is crucial for the industrialized application of biomass. In this paper, the catalytic effect of potassium additives (KCl, KOH and K2CO3) on lignin pyrolysis was studied using two Cβ-O type lignin related polymers with a carbonyl group (C O polymer) and a hydroxyl group (OH polymer), respectively, on Cα. With or without potassium additives, the two polymers were injected into a thermogravimetric analyser coupled to a Fourier transform infrared spectrometer (TG-FTIR) and a CDS pyrolyser equipped with a gas chromatography and a mass spectrometer (Py-GC/MS). The results show that the catalytic effect of potassium additives is greatly affected by the associated anion. KOH and K2CO3 strongly reduced the thermal stability of the two polymers and increased the char yield of their pyrolysis, while limited effect of KCl was observed. A promoting effect of KOH and K2CO3 was also observed on the removal of side chains such as methoxy, acetyl and hydroxyethyl groups leading to the formation of CO2 and making phenol the main product. Furthermore, the depolymerization of C O polymers through Cβ-O bond cleavage were promoted by KOH and K2CO3. Finally, the catalytic mechanism of potassium and the overall pathway of pyrolysis of the two polymers were elucidated in this study.

Nuclear power plant, nuclear reactors and nuclear powered ship exhaust contains a large amount of gaseous radioactive iodine, and can damage to the workplace and the surrounding environment. The quantitative test to remove methyl iodide and the qualitative test for removing stable iodine were investigated using the impregnated coal-based activated carbons and coal-based activated carbons as adsorbents. The research conducted in this work shows that iodine residues were under 0.5 μg/ml after adsorption treatment and the decontamination factor of the coal-based activated carbon for removing the stable iodine was more than 1000, which can achieve the purpose of removing harmful iodine, and satisfy the requirement of gaseous waste treatment of nuclear powered vessel and other nuclear plants.

A pair of separation column packed with different hydrogen absorption materials (Pd/k and 4A molecular sieves) respectively, whose hydrogen isotopic effect is opposite, is used in Thermal Cycling Absorption Process (TCAP), and its result of hydrogen isotopes separation is better than the traditional TCAP. A dynamic simulation method for the pair of column TCAP system is developed. For a certain percentage of binary gas mixtures of hydrogen isotopes (H2 and D2) injected into the twin columns system, from simulation results, it can be obtained the binary gas concentration distribution in the two columns after a different number of cycles. Furthermore, the separation process can be optimized. Moreover, it can be seen that the hydrogen isotopes separation effect of twin columns TCAP is almost twice that of the traditional TCAP.

In order to support the tritium production and recycling in the fuel cycle system of fusion reactors, the thermal cycling absorption process (TCAP), which is a semi-continuous chromatographic process for hydrogen isotope separation, has been developed for years. The hydrogen isotopes separation capacity mostly depends on the efficiency of the separation columns, therefore, evaluating different column structure designs and packing materials for their separation efficiency is significative. In this work, a unique design of separation column apparatus with the hot/cold cycling system has been developed. Its unique feature is the different separation columns can be changed for testing several factors such as particle size of packing material, fill density and uniformity, column structure on the influence of the column efficiency. Moreover, the methods to measure efficiency of the separation column have been introduced. The experimental results show that the displacement chromatographic method is more suitable for this apparatus to analyze the column efficiency.

The congenital long QT syndrome is a heterogeneous genetic disease associated with delayed cardiac repolarization, prolonged QT intervals, the development of ventricular arrhythmias and sudden death. Type 2 congenital long QT syndrome (LQT2) results from KCNH2 or hERG gene mutations. hERG encodes the K(v)11.1 alpha subunit of the rapidly activating delayed rectifier K(+) current in the heart. Studies of mutant hERG channels indicate that most LQT2 missense mutations generate trafficking-deficient K(v)11.1 channels.To identify the mechanism underlying G572R-hERG by using molecular and electrophysiological analyses.To elucidate the electrophysiological properties of the G572R-hERG mutant channels, mutant hERG subunits were heterologously expressed in HEK293 cells alone or in combination with wild-type (WT)-hERG subunits. Patch-clamp techniques were used to record currents, and double immunofluorescence protein tagging and Western blotting were performed to examine the cellular trafficking of mutant subunits. When expressed alone, G572R-hERG subunits were not present in the cell membrane and did not produce detectable currents. When coexpressed with WT-hERG subunits, G572R-hERG decreased current density and altered gating properties of the WT-hERG channel.The hERG-associated missense mutation G572R, like most LQT2 missense mutations, generates a trafficking-deficient phenotype. Furthermore, G572R-hERG causes a loss of function in hERG by a strong dominant negative effect on the WT-hERG channel.HISTORIQUE : Le syndrome du QT long congénital est une maladie génétique hétérogène associée à un retard de la repolarisation cardiaque, à des intervalles QT prolongés, à l'apparition d'arythmies ventriculaires et à une mort subite. Le syndrome du QT long congénital de type 2 (QTL2) est causé par des mutations du gène KCNH2 ou hERG. Le gène hERG code la sous-unité alpha K11.1 du canal K+ redresseur retardé du cœur qui s'active rapidement. Des études des canaux hERG mutants indiquent que la plupart des mutations faux-sens QTL2 produisent des canaux K11.1 au trafic défectueux. OBJECTIF : Dépister les mécanismes sous-jacents du canal G572R-hERG au moyen d'analyses moléculaires et électrophysiologiques. MÉTHODOLOGIE ET RÉSULTATS : Afin d'établir les propriétés électrophysiologiques des canaux mutants G572R-hERG, les sous-unités mutantes hERG étaient exprimées de manière hétérologue dans des cellules HEK293, seules ou en combinaison avec des sous-unités hERG de type sauvage (WT). Les techniques du patch-clamp ont permis d'enregistrer les courants, tandis que le marquage des protéines par double immunofluorescence et le transfert Western ont permis d'examiner le trafic cellulaire des sous-unités mutantes. Exprimées seules, les sous-unités G572R-hERG étaient absentes de la membrane cellulaire et ne produisaient pas de courants décelables. Coexprimé avec les sous-unités WT-hERG, le canal G572R-hERG réduisait la densité du courant et modifiait les propriétés de synchronisation du canal WT-hERG. CONCLUSION : La mutation faux-sens du gène G572R associée au gène hERG, comme la plupart des mutations faux-sens QTL2, produit un phénotype au trafic défectueux. De plus, le canal G572R-hERG entraîne une perte de fonction du gène hERG par son puissant effet négatif dominant sur le canal WT-hERG.