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Based on the experiments of isothermal forging wedge-shaped samples, Deform-3D numerical simulation software was used to confirm the strain distribution in the wedge-shaped samples. The effect of deforming temperature and strain on abnormal grain growth(AGG) in extruded FGH96 superalloy was examined. It is found that when the forging speed is 0.04 mm/s,the critical AGG occurring temperature is 1100℃,and the critical strain is 2%.AGG does not occur within 1000-1070℃,but still shows the feature of ‘critical strain’,and the region with strain of 5%-10% has the largest average grain size.AGG can be avoided and the uniform fine grains can be gained when the strain is not less than 15%.

The separation and purification effect of chromatographic column on tetrodotoxin was studied, which provided a reference for the separation and purification process of tetrodotoxin. The raw material for this experiment was the liver of Takifugu pseudommus, TTX was extracted from the liver, and the column chromatography technology by the loading of neutral alumina column, activated carbon column, CM HF and D152 weak acid cation exchange resin column was used to determine theoptimal pH, adsorption rate and recovery rate of liquid. According to the results of the adsorption rate and purification recovery rate of the four columns, the adsorption rate and recovery rate of the D152 weakly acidic cation exchange column were 91.97% and 93.98%, respectively, and the column was effective in purifying tetrodotoxin with low loss rate. Finally, by D152 column the crude tetrodotoxin extract was separated and purified. The raw material was Takifugu pseudommus liver. The crude extract obtained from liver homogenization was purified and separated by D152 column, and then was crystallized to obtain crude tetrodotoxin with a purity of 80%. This study provides a useful reference for the separation and purification process of tetrodotoxin. [ABSTRACT FROM AUTHOR]

As the founder of American psychology, James established the first psychological laboratory in America. However, he did few experiments, and even on some public occasions he was openly against experimental psychology and laboratory methods. Even so, he exerted a profound impact on American experimental psychology. In this paper, the author explores a number of little known historical facts about James' experimental psychology, and re-evaluates the relationship between James and experimental psychology. [ABSTRACT FROM AUTHOR]

As an important component of urban green spaces, greenhouse gas uptake or emissions from urban lawns cannot be ignored. However, studies of greenhouse gas fluxes from subtropical urban lawns are relatively sparse. The static chamber-gas chromatography method was applied to monitor the ground-air exchange fluxes of various greenhouse gases(CO 2 , CH 4 , N 2 O, and CO) in typical urban lawns of Hangzhou City. Our results showed that the average fluxes had significant seasonal cycles but ambiguous diurnal variations. The grassland and the soil(naked soil without vegetation coverage) acted as sources of atmospheric N 2 O, with the average fluxes of (0.66±0.17) and (0.58±0.20) μg·(m 2 ·min) -1 for N 2 O, respectively; however, they were also sinks of CH 4 and CO, with the average fluxes of (-0.21±0.078) and (-0.26±0.10) μg·(m 2 ·min) -1 for CH 4 and (-6.36±1.28) and (-6.55±1.69) μg·(m 2 ·min) -1 for CO, respectively. The average CO 2 emission fluxes of urban grassland and soil were(5.28±0.75) and (4.83±0.91) mg·(m 2 ·min) -1 , respectively. The correlation analysis indicated that the CO 2 and N 2 O fluxes of grassland and soil were negatively correlated with precipitation, whereas the CH 4 and CO fluxes were positively correlated with it. There was no significant correlation between grassland CH 4 fluxes and soil temperature, and N 2 O fluxes had a significant negative correlation with soil temperature; the other greenhouse gas fluxes showed a significant positive correlation with soil temperature. In addition, the seasonal variation in CO 2 ( R 2 =0.371 and 0.314) and N 2 O( R 2 =0.371 and 0.284) fluxes from both grassland and soil was affected by precipitation, whereas CO fluxes ( R 2 =0.290 and 0.234) were mainly driven by soil temperature compared with the other greenhouse gases.

A high precision GC system with a pulsed discharge helium ionization detector was set up based on the commercial Agilent 7890A gas chromatography. The gas is identified by retention time and the concentration is calculated through the peak height. Detection limit of the system is about 1 x 10(-9) (mole fraction, the same as below). The standard deviation of 140 continuous injections with a standard cylinder( concentration is roughly 600 x 10(-9)) is better than 0.3 x 10(-9). Between 409.30 x 10(-9) and 867.74 x 10(-9) molecular hydrogen mole fractions and peak height have good linear response. By using two standards to quantify the air sample, the precision meets the background molecular hydrogen compatibility goal within the World Meteorological Organization/Global Atmosphere Watch (WMO/GAW) program. Atmospheric molecular hydrogen concentration at Guangzhou urban area was preliminarily measured by this method from January to November 2013. The results show that the atmospheric molecular hydrogen mole fraction varies from 450 x 10(-9) to 700 x 10(-9) during the observation period, with the lowest value at 14:00 (Beijing time, the same as below) and the peak value at 20:00. The seasonal variation of atmospheric hydrogen at Guangzhou area was similar with that of the same latitude stations in northern hemisphere.

To strengthen scientific management and sharing of greenhouse gas data obtained from atmospheric background stations in China, it is important to ensure the standardization of quality assurance and quality control method for background CO2 sampling and analysis. Based on the greenhouse gas sampling and observation experience of CMA, using portable sampling observation and WS-CRDS analysis technique as an example, the quality assurance measures for atmospheric CO,sampling and observation in the Waliguan station (Qinghai), the glass bottle quality assurance measures and the systematic quality control method during sample analysis, the correction method during data processing, as well as the data grading quality markers and data fitting interpolation method were systematically introduced. Finally, using this research method, the CO2 sampling and observation data at the atmospheric background stations in 3 typical regions were processed and the concentration variation characteristics were analyzed, indicating that this research method could well catch the influences of the regional and local environmental factors on the observation results, and reflect the characteristics of natural and human activities in an objective and accurate way.

Based on the in-situ observation results of atmospheric CO2 molar fractions at two levels (10 m and 80 m above the ground) at Longfengshan (LFS) regional background station in Heilongjiang Province during January 2009 to December 2011, this study mainly focused on the results from 10 m above the ground level (a. g. l.). The results indicated that the observed data from 10 m were strongly affected by the local sources/sinks. The differences between the 10 m and 80 m results were relatively small during the daytime (08:00-17:00) with values smaller than (0.5 +/- 0.5) x 10(-6). In spring, summer and winter, higher CO2 molar fractions were observed when surface winds came from the E-ESE-SE-SSE sectors, while, in winter, surface winds from the N-NNW-NW-WNW sectors obviously enhanced the observed values. Generally, lower CO2 values were accompanied with higher wind speed in the four seasons. This phenomenon was most obvious in winter. Based on the analysis of the observed diurnal cycles and the local meteorological conditions, the observed data from 10 m were filtered into background/non-background events. About 30.7% valid hourly data were filtered as regional background representative. The background CO2 variation displayed a peak in winter and a valley in summer with a seasonal peak to peak amplitude of (36.3 +/- 1.4) x 10(-6), which was higher than the values at similar latitude from Marine Boundary Layer (MBL) References and WMO/GAW stations. The yearly CO2 increasing rate at LFS was roughly estimated to be 2.4 x 10(-6) a(-1).

Background CO mole fractions were continuously measured at Lian'an background station in Zhejiang province from September, 2010 to February, 2012 using Cavity Ring Down Spectroscopy (CRDS) system. The diurnal variation of CO was strongly influenced by anthropogenic activities with two peaks occurring at 07:00-10:00 and 19:00-20:00 (local time). The average daily mole fraction and amplitude in summer were the lowest among four seasons with values of 314.3 x 10(-9) +/- 7.6 x 10(-9) (mole fraction, the same below) and 50.1 x 10(-9) +/- 47.9 x 10(-9), respectively. The seasonal variations displayed peak values during winter-spring period and valley in summer, which roughly consisted with those observed variations at other sites located at northern hemisphere such as Jungfraujoch in Switzerland and Waliguan in China. However, the average mole fractions were much higher than those from other stations. The amplitude of monthly CO mole fractions was 286.8 x 10(-9) +/- 19.2 x 10(-9). The cluster analysis of backward trajectories and surface wind influence might suggest that the non-background CO mole fractions at Lin'an station were mainly affected by the emissions from the megacities and industrial area on the N-NNE-ENE sectors. The maximum enhancements in spring, summer and winter all occurred on ENE sector, with a maximum value of 106.3 x 10(-9) +/- 58.0 x 10(-9) in winter.

The real-time, automatic, highly accurate and efficient system for measuring the mixing ratios of CO2, CH4, CO and N2O has been developed by combining the commercial FTIR system (Wollongong University) with an auto-sampling system and a working standard module. Based on the tests conducted, the FTIR showed the high precision and a relatively low accuracy associated with its poor determination of correction factors. The absolute error of the mixing ratio of CO was above 38.8 x 10(-9), suggesting that FTIR alone could not meet the requirement for the real time measurement. Using the working standard gases to adjust results from the FTIR significantly improved the accuracy of measurements. For both static and dynamic conditions, the discrepancies between the measured results and the real values were below 0.11 x 10(-6), 1.8 x 10(-9), 0.15 x 10(-9) and 0.5 x 10(-9) for CO2, CH4, N2O and CO respectively, meeting the requirements for the atmospheric real-time measurements. During 6 days in-situ measurements of greenhouse gas outside the lab, the precision of target gas can reach 0.05 x 10(-6), 0.2 x 10(-9), 0.07 x 10(-9), 0.5 x 10(-9) for CO2, CH4, N2O, CO, and inaccuracy can be 0.09 x 10(-6), 0.4 x 10(-9), 0.14 x 10(-9), 0.5 x 10(-9), respectively.

Impacts of surface wind direction, surface wind speed, surface air temperature and sunshine hours on the CH4 concentration at Lin'an regional atmospheric background station were studied based on the results from Jan. 2009 to Dec. 2011. The results revealed that the diurnal variation of atmospheric CH4 concentration presented a single-peak curve at Lin'an regional background station. The diurnal amplitude varied from 19.0 x 10(-9) to 74.7 x 10(-9), with the lowest value observed in the afternoon and the highest at dawn. The monthly mean CH4 concentrations varied from 1955.7 x 10(-9) to 2036.2 x 10(-9), with the highest concentration observed in autumn and the lowest in spring. The wind directions NE-SSE could induce higher CH4 concentrations while SW-NNW wind directions had negative effects on the observed results. The CH4 concentration turned out to be lower with higher surface wind speed. With the increase of surface air temperature or sunshine hours, the CH4 concentration went up first till reaching a peak, and then decreased.

Background CH4 concentrations were continuously measured at the 4 WMO/GAW stations [Waliguan in Qinghai (WLG), Lin'an in Zhejiang (LAN), Shangdianzi in Beijing (SDZ), and Longfengshan in Heilongjiang (LFS)] by Cavity Ring Down Spectroscopy system. From 2009 to 2010, the diurnal cycle of hourly average CH4 concentration at LAN was found to be similar in all four seasons, with the highest level detected at 05:00 (Beijing Time) and the lowest at about 14:00. Similar CH4 diurnal cycles were observed at LFS in the summer time. However, the daily amplitude was much higher than that at LAN and reached 216. 8 x 10(-9) (molar ratio). For SDZ station, there were similar trends in spring, autumn and winter. The daily average concentration in the summer was much higher than those of the other seasons and reached the highest at about 20:00. No apparent CH4 diurnal cycle was observed at the WLG station during the whole year. The seasonal variations were obvious at the three regional stations (LAN, SDZ, LFS). The background concentration was the lowest in July at LAN while reached the highest level in August at LFS. The yearly background concentration variation at LFS displayed a "W" pattern. At LFS and SDZ, the wintertime CH4 concentrations were higher than those in spring and autumn. WLG represented a clean area and its CH4 value was the lowest among the four stations with the monthly average amplitude to be about 11.5 x 10(-9). At all three regional stations, non-background data accounted for more than 70% of the whole data. Cluster analysis of 3 day backward trajectories corresponding to the high CH4 concentration (WLG: CH4 > 1 870 x 10(-9), LFS: CH4 > 2100 x 10(-9), LAN: CH4 > 2 150 x10(-9), SDZ: CH4 > 2050 x 10(-9)) data points suggested that the high CH4 level measured in summer might be associated with the air mass transportation.

In-situ GC-FID system for atmospheric CH4 and CO mixing ratio measurements at the Shangdianzi (SDZ) GAW regional station in Beijing was designed and optimized in 2009 based on a comparable system at the Waliguan GAW global station in Qinhai. Results from this study indicate that the system's precisions for CH4 and CO are higher than 0.03% and 0.45% respectively, which can meet the quality target on background greenhouse gas observations by the World Meteorology Organization's Global Atmosphere Watch (WMO/GAW) program. The selection method of working standards for this system was established: two working standards (WH for the high concentration and WL for the low concentration) were selected, the concentrations of CH4 and CO in these two standards can cover the ambient mixing ratios of CH4 (2 007.1 x 10(-9) and 1 809.5 x 10(-9)) and CO (405.6 x 10(-9) and 123.8 x 10(-9)), an injection sequence was programmed so that the two standards were analyzed alternatively for every three runs. The measurement accuracies are high, as shown by the standard deviations less than 1.7 x 10(-9) and 1 x 10(-9), for CH4 and CO, respectively. This method has been applied to in-situ measurement of atmospheric CH4 and CO in North China.

To strengthen scientific management and sharing of greenhouse gas data obtained from atmospheric background stations in China, it is important to ensure the standardization of observations and establish the data treatment and quality control procedure so as to maintain consistency in atmospheric carbon dioxide (CO2) and methane (CH4) measurements from different background stations. An automated gas chromatographic system (Hewlett Packard 5890GC employing flame ionization detection) for in situ measurements of atmospheric CO2 and CH4 has been developed since 1994 at the China Global Atmosphere Watch Baseline Observatory at Mt. Waliguan, in Qinhai. In this study, processing and quality control flow of CO2 and CH4 data acquired by HP ChemStation are discussed in detail, including raw data acquisition, data merge, time series inspection, operator flag, principal investigator flag, and the comparison of the GC measurement with the flask method. Atmosphere CO2 and CH4 mixing ratios were separated as background and non-background data using a robust local regression method, approximately 72% and 44% observed values had been filtered as background data for CO2 and CH4, respectively. Comparison of the CO1 and CH, in situ data to the flask sampling data were in good agreement, the relative deviations are within +/- 0.5% for CO2 and for CH4. The data has been assimilated into global database (Globalview-CO2, Globalview-CH4), submitted to the World Data Centre for Greenhouse Gases (WDCGG), and applied to World Meteorological Organization (WMO) Greenhouse Gas Bulletin and assessment reports of the United Nations Intergovernmental Panel on Climate Change (IPCC).