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Aiming at the high gas content at the wellhead and drainage outlet of coalbed methane well site, which affects the normal safety production and is a serious waste of resources. The shortages of the existing wellhead sealing device and water pipeline gas separation device are analyzed, the gas collection technology for the coalbed methane well site is proposed. The self-adjusting deflected wellhead sealing device and the water pipeline gas separation and collection device are introduced, and the process flow of gas separation and collection in gas- containing water pipeline of coalbed methane well is designed. The simulation test shows that the simulation test shows that the technology can separate and pressurize the gas in the gas-liquid mixture up to 0.2 MPa, which verifies the feasibility of this technology.

Based on the daily meteorological data of 124 agricultural meteorological sites during 1977-2010 in Yunnan Province, using recommended Penman-Monteith formula by FAO, water requirement and irrigation requirement index in the growth period of flue-cured tobacco were calculated to analyze their spatial and temporal characteristics and change patterns. The results showed that water requirements of flue-cured tobacco in root extending, vigorous, mature periods and field growth period during 1977-2010 were 76.73-174.73, 247.50-386.64, 180.28-258.14 and 528.18764.08 mm, respectively, and the water requirement of vigorous period was the highest. The average irrigation demand index of each period was -0.02, 0.38, 0.17 and 0.26, respectively. Effective precipitation could meet the demand of flue-cured tobacco in root extending period. Water requirement of flue-cured tobacco in Yunnan Province decreased annually, and the rates of water requirement under the climate change trend in the four periods abovementioned were -12.42, -21.46, -7.17 and -47.15 mm .(10 a)-1, respectively. The smallest irrigation demand index was observed in Dehong, and the largest in Diqing. The irrigation demand indexes of Dehong, Xishuangbanna and Puer regions were negative in flue-cured tobaccofield growth period. The reference crop evapotranspiration, water requirement and effective precipitation decreased, but the irrigation requirement and irrigation requirement index increased with the increase of latitude. The effective precipitation decreased, but the irrigation requirement and irrigation requirement index increased with the increase of altitude. [ABSTRACT FROM AUTHOR]

There exists blind area for low altitude surveillance radar and the cost of Automatic Dependent Surveillance-Broadcast (ADS-B) equipment is high. To solve above problems, a navigation surveillance system system for low altitude airspace general aviation aircraft is proposed which is based on the combination of Beidou satellite navigation system(BDS) and mobile public network communications. Airborne system uses BDS/GPS dual navigation receiver to obtain information, and the airborne information is reliably sent to the ground control center by the mutually complementary communication mechanism of mobile public network communication system and BDS, and also the receiver can receive the command from the ground control center. At the same time, in consideration of BDS communication resource, the system designs the function of position storage when mobile public network communication is in blind are. The system features low cost and no electrical crosslink with other airborne equipment. The study has certain reference value for research on navigation and surveillance systems in low altitude airspace general aviation aircraft in China. [ABSTRACT FROM AUTHOR]

Particle filter algorithm has a great advantage in processing nonlinear and non-Gaussian noise problems, so an approach combining the particle filter algorithm with the log-likelihood ratio (LLR) is presented for GPS receiver autonomous integrity monitoring (RAIM). The state estimate is calculated precisely by the particle filter algorithm and LLR is used as a consistency test statistic to achieve the fault detection. By setting up the total and partial cumulative LLRs, the satellite fault is detected by checking the cumulative LLR of system state with detection threshold. The mathematical model of the algorithm is established. Meanwhile, the algorithm flow is described. Based on the real GPS data, the RAIM algorithm is tested. Experimental result demonstrates that the particle filter algorithm can accurately estimate the state of GPS receiver under conditions of non-Gaussian measurement noise, and LLR as the statistic of consistency test can effectively detect and isolate fault satellite, thus validating the feasibility and validity of particle filter and likelihood ratio methods for RAIM. [ABSTRACT FROM AUTHOR]

China has determined to develop its unified national emissions trading scheme (ETS) in the next few years, considering the experiences gained in the pilot regions. Allowance allocation will be one of the core while challenging issues in that process, with significant regional differences and coordination with the existing administrative features in China to be addressed. The focus of this article is on allowance allocation in China's future national ETS, i.e. how to allocate allowances from the central government to covered enterprises. The key issue is actually the distribution of responsibilities/power between the central and regional governments in the allocation process. A novel allocation approach based on localization management and current administrative system is proposed. The central government will be responsible for the development of unified allocation methods and differentiated regional adjustment coefficients to accommodate regional differences. The provincial governments will be responsible for the selection of regional adjustment coefficients within the permitted spectrum and allocating allowances to enterprises in their regions under the supervision of the central government. This approach will allow the provincial governments certain flexibilities while at the same time guidance and supervision could be exercised by the central government. The impacts of information asymmetry and Prisoner's Dilemma, which will be impeding the development of a unified national emissions trading market, could thus be reduced. [ABSTRACT FROM AUTHOR]

The time-control drilling technology had been used for saving the cost of drilling, shortening the construction period and reducing the risks of drilling in the process of coring and layer determination of a coalbed methane well in Jixi Basin of Heilongjiang Province. The method identified the target layer's which was characterized by combination of thin seams, controlling the speed of drilling and footage and the application of careful cut logging method, and finally coring successfully. The results showed that this technology which reduced the workload of coal drilling without coal core, saved the cost of drilling, shortened the period of drilling engineering construction and increased the efficiency of drilling, the technology was an effective method for sticking bed in coalbed methane well. [ABSTRACT FROM AUTHOR]

There are three main classes of actin nucleation factors: Arp2/3 complexes, Spire and Formin. Spire assembles microfilaments by nucleating stable longitudinal tetramers and binding actin to the growing end of the microfilament. As early as 1999, Wellington et al. identified Spire as an actin nucleating agent, however, over the years, most studies have focused on Arp2/3 and Formin proteins; there has been relatively less research on Spire as a member of the actin nucleating factors. Recent studies have shown that Spire is involved in the vesicular transport through the synthesis of actin and plays an important role in neural development. In this paper, we reviewed the structure, expression and function of Spire, and its association with disease in order to identify meaningful potential directions for studies on Spire.

Retention index (RI) is a powerful tool for gas chromatography-based structure elucidation of various compounds. In this study, linear RIs based on n -alkanes and n -fatty acid methyl esters in different temperature programs were fitted. Nearly identical first-order linearities were acquired with different temperature programs. The linear equations were y =1.0051 x +318.51 ( r 2 =1) and y =1.0362 x +562.519 ( r 2 =1) for polar (packed with polyethylene glycol) and semi-standard non-polar (packed with 5% diphenyl/95% dimethylpolysiloxane) columns, respectively. The variables x and y in the equations stand for RIs based on n -fatty acid methyl esters and n -alkanes, respectively. The established linearity was then verified using the reference RIs collected in the NIST mass spectral library, Golm metabolite library, and Fiehnmetabolite library. The RI values converted using both the acquired equations finely matched those in the references. The established relationship between the two kinds of RIs can be used to expand the RI references and decrease the number of RI acquisition experiments.

A hydrophilic interaction liquid chromatography-tandem mass spectrometry (HILIC-MS/MS) method was established for the simultaneous determination of maleic hydrazide (MH) and its two glucosides in tobacco leaves. Ultrasonic assisted extraction of MH and its glucosides was performed using acetonitrile-methyl tert -butyl ether-water (7:10:13, volume ratio). The extraction solution was then centrifuged, and the subnatant was transferred for solvent replacement using acetonitrile. The extract in acetonitrile was then analyzed using HILIC-MS/MS. Method validation was performed, and the linear ranges for MH and MH- O -β -D-glucoside were 5-150 mg/kg with correlation coefficients ( r 2 ) greater than 0.9971 for matrix-matched calibration curves. Limits of detection for MH and MH- O -β -D-glucoside were 0.5 mg/kg and 0.3 mg/kg, and limits of quantification were 1.0 mg/kg and 0.8 mg/kg, respectively. The recoveries were in the range of 83.1%-112.3% at three spiked levels (10, 40, 80 mg/kg), with intra-day repeatability of 2.7% and 3.8%, inter-day repeatability of 8.3% and 7.1% at 40 mg/kg. The established method was used for the study of MH metabolism in tobacco leaves. By the 28th day after MH spraying, the content of MH in tobacco leaves had decreased by 80.8%, of which only 7.6% transformed to MH-glucosides. The disposition of the remainder needs to be studied.

Flavonoids are very important secondary metabolites for tobacco plants. They are also considered as important flavor precursors for cigarettes. A method of ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was established for the simultaneous determination of 12 flavonoids in tobacco leaves. The developed method determined 10 more flavonoids compared to the traditional method. A solution of methanol-water-chloroform (5:2:2, v/v/v) was used to extract the flavonoids from tobacco leaves and remove the pigment. Instrument analysis using the UPLC-MS/MS was completed in 13 min. The method validation was performed, and the results showed that the linear correlation coefficients (r2) of all the 12 flavonoids were more than 0.99. The limits of detection and the limits of quantification were in the range of 0.3-100 μg/L and 1.2-400 μg/L, respectively. Intra-day and Inter-day reproducibilities were in the range of 3.5%-7.4% and 5.2%-11.4%, respectively. The recoveries were 81.2%-111.9%. The established method was successfully used to analyze the flavonoids of tobacco leaves of 11 varieties. Significant concentration differences of the flavonoids were found among the determined varieties. Furthermore, significant positive correlation among the flavonoids with similar chemical structures (aglycones and their related glycosides, glycosides with the same aglycone, and similar aglycones) was found using the acquired data.

Based on the daily meteorological data of 124 agricultural meteorological sites during 1977-2010 in Yunnan Province, using recommended Penman-Monteith formula by FAO, water requirement and irrigation requirement index in the growth period of flue-cured tobacco were calculated to analyze their spatial and temporal characteristics and change patterns. The results showed that water requirements of flue-cured tobacco in root extending, vigorous, mature periods and field growth period during 1977-2010 were 76.73-174.73, 247.50-386.64, 180.28-258.14 and 528.18-764.08 mm, respectively, and the water requirement of vigorous period was the highest. The average irrigation demand index of each period was -0.02, 0.38, 0.17 and 0.26, respectively. Effective precipitation could meet the demand of flue-cured tobacco in root extending period. Water requirement of flue-cured tobacco in Yunnan Province decreased annually, and the rates of water requirement under the climate change trend in the four periods abovementioned were -12. 42, -21.46, -7.17 and -47.15 mm . (10 a)-1, respectively. The smallest irrigation demand index was observed in Dehong, and the largest in Diqing. The irrigation demand indexes of Dehong, Xishuangbanna and Puer regions were negative in flue-cured tobacco field growth period. The reference crop evapotranspiration, water requirement and effective precipitation decreased, but the irrigation requirement and irrigation requirement index increased with the increase of latitude. The effective precipitation decreased, but the irrigation requirement and irrigation requirement index increased with the increase of altitude.

Graphited carbon nitride materials (g-C3N4) with high visble-light response were synthesized by thermal condensation of melamine at varied temperature. The microstructure and optical property of as achieved catalysts were investigated by XRD, SEM and UV-Vis techniques, respectively. Moreover, rhodamine B solution was applied to measure the catalytical performance under the irradiation of different sources of light. The results showed that the major structures of g-C3N4 were kept, though lots of blocks were scattered on the surface because of the damage of lamellar structure caused by the high temperature. As the thermal temperature was increased, the adsorptions of light were greatly enhanced in both UV and Vis region, which might be due to the decrease in reflection and the increase in refraction at the lumpy surface. In the degradation of rhodamine B solution, all the samples showed high photocatalytic activities under the irradiation of both Visible-light and sunlight, and 94. 8% (60min, under Vis-light) and 91. 1% (90min, under sunlight) of RhB were degraded when the thermal temperature was 580°C. This research would greatly enlighten the studies of environmental purification using clean green energy.

In order to identify Ilex Kudingcha, two kinds of models of artificial neural networks (ANN), i.e. competitive neural network and back propagation neural network, were used to analyze their infrared spectra. Ilex Kudingcha samples were collected by Fourier transform infrared (FTIR) spectra. Twenty five samples were gathered as a train set, and 11 samples as a test set, then their training was performed using two networks each. The results show that the identification of Ilex Kudingcha from different areas can be effectively performed with the competitive neural network and BP network, but the competitive neural network is used in the identification of different grades of Ilex Kudingcha. The results were better in training speed and accuracy with the competitive neural network. In conclusion, the competitive neural network combined with FTIR spectroscopy is a good method for the identification of Ilex Kudingcha.

In the present article, two new indexes, common peak ratio and variant peak ratio, were applied and their values were calculated by means of sequential analysis, in which each Ilex Kudingcha sample s IR fingerprint spectra were set up and the common peak ratio sequences were arranged in order of size in comparision with other samples. As a result, the method could be used to distinguish Ilex Kudingcha of different areas and classes. The duel-index sequential analysis enables us to distinct two or more herb's IR fingerprints. It is a new method to analyze IR fingerprint spectra, and can used in line with the characteristics of traditional Chinese medicine.

Background & Objective: It was reported that urinary modified nucleosides with abnormally high amounts were found in many cancer patients. This study was designed to investigate the usefulness of urinary nucleosides in the diagnosis of gastric carcinoma., Methods: The concentrations of 15 kinds of urinary nucleosides from 50 healthy persons and 48 patients with gastric carcinoma were determined by high-performance liquid chromatography (HPLC). Of 48 patients with gastric carcinoma, 25 underwent serum CEA examination., Results: The average levels of 14 kinds of urinary nucleosides, m5U excepted, from patients with gastric carcinoma were higher than those from health persons (P< 0.05). Pseu 22.91+/-4.90, 34.87+/-21.41; U 0.34+/-0.32, 0.62+/-0.82; A 0.58+/-0.16, 0.96+/-0.75; C 0.17+/-0.15,0.24+/-0.19; m5U 0.03+/-0.07,0.07+/-0.06; I 0.26+/-0.10, 0.43+/-0.36; m1I 1.34+/-0.34, 2.44+/-1.39; ac4C 0.75+/-0.24, 1.08+/-0.72; G 0.09+/-0.04, 0.14+/-0.10; X 1.20+/-0.42, 1.90+/-1.09; m2G 0.61+/-0.16, 1.00+/-0.69; m6A 0.04+/-1.13, 0.07+/-0.08; m1A 2.26+/-0.56, 3.71+/-2.21; m22G 1.34+/-0.27, 2.25+/-1.39; m1G 0.80+/-0.25, 1.41+/-0.86. The level of nucleoside I was positively correlated with the tumor size (P< 0.05). The level of nucleoside X was positively correlated with lymph node metastasis (P< 0.05). Using the concentrations of 15 nucleosides as the data vectors, principal component analysis was applied to classify gastric cancer patients and normal adults, 63%(30/48) of cancer patients were correctly classified, in which the identification rate was higher than that of CEA method (12%)., Conclusion: Urinary modified nucleoside increased in the patients with gastric carcinoma, and it may be helpful in the diagnosis of gastric carcinoma.

A method for the determination of urinary nucleosides with reversed-phase high performance liquid chromatography is described. After nucleosides were extracted from urine on phenyl boronic acid affinity chromatography, the analysis was performed on a column (4.6 mm i.d. x 250 mm, 5 microns) at 22 degrees C using a linear gradient elution comprising 25 mmol/L KH2PO4 solution (pH 4.55) and 60% methanol in water with UV detection at 260 nm. This method was used for the determination of 15 urinary nucleosides of 41 intestinal cancer patients and 52 normal adults. The results showed that the average concentrations of 12 urinary nucleosides from intestinal cancer patients were much higher than those of normal adults with P < 0.001. Using the concentrations of 15 nucleosides as the data vectors, principal component analysis was applied to classify intestinal cancer patients and normal adults and 76% (31/41) of the cancer patients were correctly classified. It is concluded that the method is sensitive, reliable and suitable for basic research and clinical applications to malignant tumours.