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The effect of thermal exposure on microstructure and creep properties of a fourth-generation nickel-based single crystal superalloy was investigated. The thermal exposure of samples after the full heat treatment was carried out at 1000 °C, 1100 °C and 1140 °C for 100 h and 200 h. The γ′ coarsening, γ′ rafting and γ channel widening were observed in samples after thermal exposure. When the thermal exposure time was constant, the morphology of γ′ phase in the alloy evolved significantly with increasing aging temperature. The interfacial dislocation networks in aged samples after creep ruptured gradually became irregular and sparse with the increase of exposure temperature. When the higher exposure temperature was used, enlargement of the defect pores was observed in samples, the microcracks were more likely to initiate and propagate at the corner of these pores. After aging at 1000 °C for 100 h, the creep life at 1140 °C/137 MPa was slightly longer than that of heat-treated sample, which could be attributed to the slightly coarsened γ′ phase, homogenization of refractor elements. In contrast, the creep life of sample exposed at 1140 °C for 100 h was greatly decreased. The decrease of creep life was dominated by the rafting of γ′ phase, the irregular interfacial dislocation networks as well as the enlargement of homogenization pores.

A novel nickel-based single crystal superalloy with low density had been designed and the creep deformation mechanisms of the experiment alloy under two conditions (1050 °C/200 MPa and 1100 °C/137 MPa) had been systematically discussed. The topological inversion had been observed after fracture under the above two conditions. The effects of temperature and stress on creep life of the experiment alloy had been found no significant difference under the two conditions. It was indicated that the small decrease in temperature exerted limited influence on the creep behaviors of single crystal superalloys in the range of high temperature.

The Portevin-Le Châtelier (PLC) effects in a wrought Ni-base superalloy with different γʹ precipitates contents have been investigated. Detailed analysis on the serration type of the tensile curves indicates that the γʹ precipitates have a decisive influence on the transformation from normal to inverse PLC behavior, which is rarely proposed in other works. It is considered that the γʹ precipitates play the same role in PLC effect as temperature and strain rate for the investigated wrought Ni-base superalloy.

A compact shielding tank for portable 241Am-Be neutron source, which is used in nuclear well logging, was designed according to the Monte Carlo simulation. From inner to outer, the proposed tank has two shielding layers to shield the high- and low-energy neutrons. In this study, the shielding properties of several materials were evaluated. Tungsten was selected as the neutron moderator to build the inner layer. The thermal neutron absorber in the outer layer was made of polyethylene containing 1.2% boron carbide. The volume and weight of the new tank reduced by 86% and 54%, respectively, by using this dual-layer shielding model, when compared with those of the old shielding tank. Moreover, the simulation results indicated that the total dose rate anywhere outside the tank is less than 0.025mSv/h and that the intensity of gamma flux at the tank surface becomes lower.

Odorous volatile organic compounds (VOCs) were analysed via a thermal desorption gas chromatograph coupled with a mass spectrometer and olfactory detection port (TD-GC-MS/ODP) to characterize odour emissions from a wastewater treatment plant (WWTP). Three trained ODP assessors, screened according to the European dynamic olfactometry standard (EN: 13725), were used for the olfactory analysis. Their sensitivity to n-butanol varied within the acceptable limits. VOC samples from the WWTP were collected onto Tenax TA sorbent tubes in triplicate and each assessor analysed one tube in the same sample desorbing and analysing conditions. Intensities of odours detected from ODP were scaled from 1 to 4. The ODP assessors used their own odour descriptors based on their own experience as well as referenced descriptors on published compost and wastewater odour wheels. The ODP assessors detected a total of 32 different odorous VOCs; however, the intensities assigned by each assessor to particular VOCs varied. Moreover, some odorous VOCs were not detected by all assessors. For example, geosmin was detected by only two assessors. The use of a TD-GC-MS/ODP system for the analysis of odorous VOCs is valuable when analysed by different assessors, allowing a range of responses to specific odorants in a populations to be investigated.

Formation porosity can be determined using the boron capture gamma ray counting ratio with a near to far detector in a pulsed neutron-gamma element logging tool. The thermal neutron distribution, boron capture gamma spectroscopy and porosity response for formations with different water salinity and wellbore diameter characteristics were simulated using the Monte Carlo method. We found that a boron lining improves the signal-to-noise ratio and that the boron capture gamma ray counting ratio has a higher sensitivity for determining porosity than total capture gamma.

The odour emission characteristics of 22 recreational rivers in Nanjing were investigated and analysed. Eight odorous compounds (ammonia (NH3), hydrogen sulphide (H2S), sulphur dioxide (SO2), carbon disulphide (CS2), nitrobenzene (C6H5NO2), aniline (C6H5NH2), dimethylamine (C2H7N), and formaldehyde (HCHO)) were measured in odour emission samples collected using a custom-made emission flux hood chamber. The results showed that all odorants were detected in all monitoring rivers. NH3 was the main odorant, with emission rates ranging from 4.86 to 15.13 μg/min m2. The total odour emission rate of the Nan River, at 1 427.07 OU/s, was the highest of the all investigated rivers. H2S, NH3 and nitrobenzene were three key odour emission contributors according to their contributions to the total odour emission. A correlation analysis of the pollutants showed there was a significant positive correlation between the emission rate of NH3 and the concentration of ammonia nitrogen (NH4 +-N) and total nitrogen (TN). The H2S and SO2 emission rates had a significant positive correlation with sulphides (S2−) and available sulphur (AS) in the water and sediment. The content of TN, NH4 +-N, S2− and AS in the water and sediment affected the concentration of H2S, SO2 and NH3 in the emission gases. NH4 +-N, S2− and AS are suggested as the key odour control indexes for reducing odours emitted from these recreational rivers. The study provides useful information for effective pollution control, especially for odour emission control for the recreational rivers of the city. It also provides a demonstrate example to show how to monitor and assess a contaminated river when odour emission and its control need to be focused on.

Shanlan rice wine is made by a unique method by removing the saccharified liquid from wine mash constantly since it appeared during saccharification and fermentation. The objective of this study is to find the advantages of this technique of wine making by analyzing data of shanlan wine fermentation. Since the liquid was removed, the mash (rice) bed was fluffier than immersed in the saccharified liquid, under ambient condition constantly and it is favorable for starch degradation. This technique made shanlan rice wine tasted sweet and slightly acidic, lower content of alcohol and higher alcohol than in other non-distilled rice wines.

A 2-year monitoring study was conducted at a sewer pumping station to investigate volatile sulfur compound (VSC) and volatile organic compound (VOC) emission dynamics over a range of timescales to gain an understanding of how they impact the design and execution of sewer odorant monitoring. It is demonstrated that the sewer system was highly dynamic and influenced by a range of processes at different time scales. Based upon odor activity values, hydrogen sulfide and methyl mercaptan had strong potential to be odorous, while dimethyl sulfide and dimethyl disulfide were potentially odorous at source concentrations. In general, VOCs were not likely to be odorous at source concentrations, although some episodic elevations in aromatic hydrocarbon and terpene concentrations to potentially odorous levels were observed and as a result VSCs are the primary targets for sewer odor abatement. A strong diurnal emission cycle was observed, with dynamic ranges (ratio of peak to average concentration) between 2.34 and 4.55 for specific VSCs and 1.82 to 10.6 for specific VOCs. Interday variability over a 1-week period was relatively low for many VSCs, with coefficients of variance generally ranging from 11 to 30%, while VOC emissions had greater variability, with coefficients of variance ranging from 29 to 220%.

Oil palm (Elaeis guineensis Jacq.) is one of the highest oil-yield crops in the world. A Δ12-desaturases associated with the primary steps of long-chain polyunsaturated fatty acid (LC-PUFA) biosynthesis were successfully cloned from oil palm and their functions identified. The open reading frames (ORFs) of egFAD2 (GenBank accession: KT023602) consisted of 1176bp and code for 391 amino acids. Their deduced polypeptides showed 75-93% identity to microsomal Δ12-desaturases from other higher plants, and each contained the three histidine clusters typical of the catalytic domains of such enzymes. RT-PCR experiment indicated that the egFAD2 gene exhibited the highest accumulation in the mesocarp of fruits at 120-140 DAP (i.e. the fourth period of fruit development) and, despite having different expression levels, the other four stages were at significantly lower levels compared with the fourth stage. Plasmid pYES2-egFAD2 was transformed into Saccharomyces cerevisiae strain INVSc1 using lithium acetate method for expression under the induction of galactose. Yeast cells transformed with plasmid constructs containing egFAD12 produced an appreciable amount of linoleic acids (18:2(Δ9,)(12)), not normally present in wild-type yeast cells, indicating that the genes encoded functional Δ12-desaturase enzymes.

Odourous emissions from sewer networks and wastewater treatment plants (WWTPs) can significantly impact a local population. Sampling techniques such as wind tunnels and flux hood chambers are traditionally used to collect area source samples for subsequent quantification of odour emission rates using dilution olfactometry, however these methods are unsuitable for assessing liquid samples from point sources due to the large liquid volumes required. To overcome this limitation, a gas phase sample preparation method was developed for assessing the total Odour Emission Ability (OEA) from a liquid sample. The method was validated using two volatile organic sulphur compounds (VOSCs), dimethyl-trisulphide (DMTS) and bismethylthiomethane (BMTM) that are frequently detected from sewers and WWTPs and are relatively stable compared with common VOSCs like mercaptan or methyl mercaptan. The recovery rates of DMTS and BMTM were quantified by injecting a known volume of a standard liquid sample into Tedlar bags using a static injection and a dynamic injection methodology. It was confirmed that both dynamic and static injection methods at ambient condition achieved high recovery rates with no need to consider increasing evaporation by elevating the temperature. This method can also be used to assess odour removal effectiveness of liquids by comparing the OEA before and after the treatment tests. Two application examples were presented.

Odour emissions from aluminium processing can cause an impact on local communities surrounding such facilities. Of particular concern is fugitive odours emitted from the handling and use of refinery condensate streams, particularly the digestion condensate. This study evaluated the application of using catalytic ozonation to treat alumina refinery condensate in order to remove the potential emission of odourous compounds from the industrial wastewater. The technical challenges in treating the alumina refinery condensate are the high pH and temperatures of the wastewater effluent (over 80 °C and pH above 10) due the industrial process. The odour removal efficiencies for different catalysts (FeCl3, MnO, and MnSO4) under experimental conditions in terms of controlled pH, temperature and ozone dosage were determined before and after ozone treatment using dynamic olfactometry. The result demonstrated that the addition of both FeCl3 and MnO catalysts improved odour removal efficiencies during the ozonation of alumina condensates at similar pH and temperature conditions. FeCl3 and MnO had similar enhancement for odour removal, however MnO was determined to be more appropriate than MnSO4 for odour removal due to the colouration of the treated condensate.

Odorous emissions from sewers and wastewater treatment plants are a complex mixture of volatile chemicals that can cause annoyance to local populations, resulting in complaints to wastewater operators. Due to the variability in hedonic tone and chemical character of odorous emissions, no analytical technique can be applied universally for the assessment of odour abatement performance. Recent developments in analytical methodologies, specifically gas chromatography, odour assessment approaches (odour wheels, the odour profile method and dynamic olfactometry), and more recently combined gas chromatography-sensory analysis, have contributed to improvements in our ability to assesses odorous emissions in terms of odorant concentration and composition. This review collates existing knowledge with the aim of providing new insight into the effectiveness of sensorial and characterisation approaches to improve our understanding of the fate of odorous emissions during odour abatement. While research in non-specific sensor array (e-nose) technology has resulted in progress in the field of continuous odour monitoring, more successful long term case-studies are still needed to overcome the early overoptimistic performance expectations. Knowledge gaps still remain with regards to the decomposition of thermally unstable volatile compounds (especially sulfur compounds), the inability to predict synergistic, antagonistic, or additive interactions among odorants in combined chemical/sensorial analysis techniques, and the long term stability of chemical sensors due to sensor drift, aging, temperature/relative humidity effects, and temporal variations. Future odour abatement monitoring will require the identification of key odorants to facilitate improved process selection, design and management.

Summary This article introduces a development of pulsed neutron uranium logging instrument. By analyzing the temporal distribution of epithermal neutrons generated from the thermal fission of 235 U, we propose a new method with a uranium-bearing index to calculate the uranium content in the formation. An instrument employing a D-T neutron generator and two epithermal neutron detectors has been developed. The logging response is studied using Monte Carlo simulation and experiments in calibration wells. The simulation and experimental results show that the uraniumbearing index is linearly correlated with the uranium content, and the porosity and thermal neutron lifetime of the formation can be acquired simultaneously.

This article introduces a development of pulsed neutron uranium logging instrument. By analyzing the temporal distribution of epithermal neutrons generated from the thermal fission of (235)U, we propose a new method with a uranium-bearing index to calculate the uranium content in the formation. An instrument employing a D-T neutron generator and two epithermal neutron detectors has been developed. The logging response is studied using Monte Carlo simulation and experiments in calibration wells. The simulation and experimental results show that the uranium-bearing index is linearly correlated with the uranium content, and the porosity and thermal neutron lifetime of the formation can be acquired simultaneously.

The gas-liquid absorption method, using an impinger as an extracting device, is the most common method for quantifying most gaseous pollutants. The performance of conventional impingers was studied, and several modified impingers were tested. It was found that the sampling efficiency varied from impinger to impinger, which resulted from back-pressure differences between impingers. The back-pressure of ten tested impingers ranged between 160 mm to 520 mm water gage when a 50 mL absorbing solution was used, which caused the ammonia concentration coefficients of variations to be up to 15%. It was also verified that an open bubble distribution tube could be used to eliminate back-pressure variations between impingers. Nearly identical back-pressure (44 ± 4 mm water gage) could be obtained. This modification can improve measurement repeatability significantly and reduce the coefficient of variation of measurements to 1.2%. With this modification to the impingers, greater accuracy, repeatability and comparison of results can be achieved in the measurement of gaseous pollutants in air.

Wind-tunnel systems are widely used for collecting odour emission samples from surface area sources. Consequently, a portable wind-tunnel system was developed at the University of New South Wales that was easy to handle and suitable for sampling from liquid surfaces. Development work was undertaken to ensure even air-flows above the emitting surface and to optimise air velocities to simulate real situations. However, recovery efficiencies for emissions have not previously been studied for wind-tunnel systems. A series of experiments was carried out for determining and improving the recovery rate of the wind-tunnel sampling system by using carbon monoxide as a tracer gas. It was observed by mass balance that carbon monoxide recovery rates were initially only 37% to 48% from a simulated surface area emission source. It was therefore apparent that further development work was required to improve recovery efficiencies. By analysing the aerodynamic character of air movement and CO transportation inside the wind-tunnel, it was determined that the apparent poor recoveries resulted from uneven mixing at the sample collection point. A number of modifications were made for the mixing chamber of the wind-tunnel system. A special sampling chamber extension and a sampling manifold with optimally distributed sampling orifices were developed for the wind-tunnel sampling system. The simulation experiments were repeated with the new sampling system. Over a series of experiments, the recovery efficiency of sampling was improved to 83-100% with an average of 90%, where the CO tracer gas was introduced at a single point and 92-102% with an average of 97%, where the CO tracer gas was introduced along a line transverse to the sweep air. The stability and accuracy of the new system were determined statistically and are reported.