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To determine the occurrence of mineral oil hydrocarbons (MOH) in food contact papers in China, and to investigate the potential sources of MOH contamination, a total of 159 food contact papers and raw materials were analysed by off-line solid-phase extraction-gas chromatography flame ionisation detection (SPE-GC-FID) and a GC-MS method. The migration of MOH from food contact papers into Tenax, olive oil or 50% ethanol under the worst foreseeable conditions of use was determined. The results indicated that the occurrence of MOH in China is of a potential health risk concerning the migration of mineral oil saturated hydrocarbons (MOSH) and mineral oil aromatic hydrocarbons (MOAH) which were detected in 82.6% and 50.4% of samples, respectively. Migration of MOSH from 47.9% of samples was higher than 2 mg/kg and migration of MOAH from 32.2% samples exceeded 0.5 mg/kg in case of the worst foreseeable condition of use. The highest mean migration of MOSH and MOAH were found in packaging papers for long-term storage (more than 6 months), with mean migration of 91.2 mg/kg and 1.4 mg/kg, respectively. Migration of MOH from printed paper was considerably higher than that of unprinted paper, validating previous findings that the printing ink is the predominant source of MOH contamination in food contact papers. Migration of MOH from paper bowls used for packing instant noodles was relatively low, suggesting the internal hollow layer may be acting as a functional barrier that could block the transfer of MOH (up to C28) through the gas phrase, even though the outer layer was made from recycled paper. High concentrations of MOSH and MOAH were also detected in de-foamers, adhesives and rosin sizing agents, indicating that the MOH contamination caused by the use of raw materials and additives should also be taken into consideration. [ABSTRACT FROM AUTHOR]

Mineral oil hydrocarbon (MOH) contamination of various foods in the past few decades has raised much concern due to its potential adverse health effects. Since infant formulas (IF) is the major food source for infants, it is necessary to understand MOH contamination level in IF and consequent potential food safety risks. Data on the contamination of IF by mineral oil are lacking in China. On the other hand, the analysis of MOH in food is difficult. There is no harmonised standard analytical method for testing MOHs in IF. GC-FID/MS was chosen as the analytical tool being more convenient for surveys at a national level. Fifty-one IFs comprising dairy milk-based IFs (n = 39) and goat milk-based IFs (n = 12), including different stages (Stage 1, 2 and 3), package type (metal cans and paper boxes) were collected in China market in 2018 for this survey. 17 of 51 IFs were found positive, but trace levels MOAH were found (≤0.7 mg/kg). For the positive samples, all the MOSH and MOAH hump fell into the C16-C25 fraction. MOH humps were found in all the 12 goat milk-based IFs, even 4 samples are reported with quantifiable values which are higher than the method defined LOQ. The highest quantifiable MOH contamination level of goat milk-based IFs were MOSH = 3.5 mg/kg and MOAH = 0.7 mg/kg. Further root cause analysis of contamination is highly recommended to control the MOH contamination for goat milk-based IFs. [ABSTRACT FROM AUTHOR]

Over the past decade, cooperation between China and Kazakhstan in the oil and gas sector has developed significantly. For China, security of its energy supply is a key strategic objective. This paper analyzes the evolution of Sino-Kazakh oil and gas relations, assesses their long-term prospects, and explores how Chinese demand for oil and gas could divert Kazakhstan’s hydrocarbon resources from other energy markets. The netback approach has been used to assess the prices that China will need to offer other producers in Kazakhstan. Sino-Kazakh energy and economic cooperation could create a good basis for free economic zones and development of beneficial ties for both countries. [ABSTRACT FROM PUBLISHER]

To detect oil-bearing sand in the western slope zone of Songliao Basin, China, a Landsat-7 Enhanced Thematic Mapper Plus (ETM+) image was used to identify anomalous areas caused by hydrocarbon leakage. Enhancement of the image involved three techniques including Principal Component Analysis (PCA), band ratioing and False Colour Composition (FCC). In this paper, experimental work gives a detailed PCA description of different band combinations. The best four principal components (PCs) - 1345-PC3 (the third PC image of the PCA on band 1, 3, 4, 5), 1357-PC3, 2357-PC3 and 3457- PC4 - were selected for FCC combined with band ratio layers. Based on the tonal characteristics of the existing bores and the basin boundary, differentiation of target areas in the four FCC images was achieved. Results indicated that anomalies are expressed as a halo in fuscous tone and located in the basin margin with an area of 70∼100 km2. Examination of the Ce/La ratio showed that the tonal anomalies are evidently associated with a reducing environment. [ABSTRACT FROM AUTHOR]

The Lower Cretaceous Bayingebi Formation at the Hari sag, Northern China is a significant bearing oil-gas tight reservoir in the Yin'E Basin. In order to understand petrophysical properties of the reservoirs, the diagenesis and hydrocarbon accumulation phases were investigated using casting thin sections, scanning electron microscopy (SEM), X-ray diffraction and fluid inclusion analysis. Additionally, the histories of burial evolution, organic matter thermal evolution and hydrocarbon charge are investigated. The results showed that the pore types include primary pore, intergranular pore and dissolution intragranular pore. The diagenesis of sandstone reservoirs in the process of burial and diagenesis mainly includes compaction, fracture, cementation, metasomatism and dissolution. The comprehensive analysis of various diagenetic stage indexes shows that Bayingebi Formation is in the middle diagenetic stage A-B. The homogenization temperature and salinity of fluid inclusions are low temperature and low salinity (120 °C ∼ 130 °C, 0% ∼ 9%), medium temperature and high salinity (140 °C ∼ 150 °C, 10% ∼ 17%) and high temperature and medium salinity (160 °C ∼ 170 °C, 9% ∼ 11%) respectively. According to the homogenization temperature of the inclusions and the history of burial evolution, the Bayingebi Formation has mainly three phases of hydrocarbon accumulation (100 ∼ 97Ma, 93 ∼ 87Ma, 84 ∼ 81Ma). [ABSTRACT FROM AUTHOR]

The oil-gas display of early drilling suggests a considerable exploration prospect in the Nangong Sag. Previous researchers have not analyzed the characteristics of hydrocarbon migration and accumulation from the perspective of fluid potential. We use the Hubbert flow potential model to restore the flow potential of the Nangong Sag in the Pliocene, which was a key period of hydrocarbon generation. The results show that the high value area of fluid potential is large and mainly located in the southeastern part of the study area. The southeast subsag provided fluid, and the northwest slope accumulated fluid. The fluid potential gradual decrease from the southeast subsag to the northwest slope. According to the division trough theory, the Nangong Sag is divided into 8 hydrocarbon migration and accumulation units. We suggest that migration and accumulation units III, IV and V are favorable areas for hydrocarbon exploration. The study area has favorable source-reservoir-cap, pool-forming conditions and good time allocation relationship of hydrocarbon. Based on the characteristics of fluid potential, the hydrocarbon generation and accumulation modes of migration and accumulation unit III and IV in Nangong Sag are preliminarily put forward. The research results have guiding significance for future hydrocarbon exploration in the study area. [ABSTRACT FROM AUTHOR]

Rapid and accurate estimation of soil petroleum hydrocarbon content is crucial for analyzing the degree of soil pollution and evaluating pollution status. Surface soil samples and hyperspectral measurements in the reservoir area in Lenghu Town, Qinghai Province, China, were viewed as research objects, and the correlation between different spectral forms of original data and petroleum hydrocarbon content in soil was analyzed. To improve the estimation accuracy, we proposed a solution that introduces least absolute shrinkage and selection operator (LASSO) combined with extremely randomized trees (ERT) and gradient boosting decision tree (GBDT) ensemble learning for constructing hyperspectral estimation model. The results show: LASSO algorithm can not only solve the spectral multicollinearity problem effectively but also reduce the number and calculation complexity of soil hyperspectral variables to a great extent. Compared with traditional machine learning, ERT and GBDT perform superior. In particular, the estimation accuracy of the LASSO-GBDT model is the highest. [ABSTRACT FROM AUTHOR]

Three new compounds, namely massonside C (1), massonianoside F (2), and 3, 8-dimethyl- herbacetin-7-O-β-D-glucopyranoside (3), together with five known compounds (4–8), were isolated from the fresh needles of Pinus massoniana. Their structures were established by 1D, 2D NMR, HRMS and comparison with the literature data. The absolute configuration of 1 was confirmed by a combination of X-ray single crystal analysis. All isolated compounds were evaluated for the protective effect of human umbilical vein endothelial cells against oxidative damage. [ABSTRACT FROM AUTHOR]

Based on the seismic data analysis, source rock geochemistry and reservoir physical properties, the source reservoir allocation and reservoir forming conditions in the Linhe-Jilantai area in Hetao Basin were studied. The results show that the source rocks of the Lower Cretaceous and the Oligocene in the study area reach the standard of fair-good source rocks, and the lithology of reservoirs is mainly feldspar sandstone and lithic feldspathic sandstone with good physical properties. Combined with vertical and lateral migration pathways, three hydrocarbon accumulation models of near source, far source and inside source are proposed. The research results can provide reference and guidance for the further hydrocarbon exploration in Hetao Basin. [ABSTRACT FROM AUTHOR]

A new natural product, 3α,19-dihydroxyl-ent-pimara-8(14),15-diene (1), which possesses an α-orientation hydroxymethyl at C-4 and ∆8,14 groups, as well as eight known compounds, was isolated from the rhizomes of Ricinus communis. The structure of 1 was elucidated by extensive spectroscopic methods and its absolute configurations were confirmed by X-ray crystallographic analysis. The inhibitory rate of 1 against protein tyrosine phosphatase 1B (PTP1B) was 49.49% at the concentration of 6.58 × 10−5 mol/L. [ABSTRACT FROM AUTHOR]

In order to study the mechanism of gas generation from the asphaltene, the thermal pyrolysis simulation experiment of the asphaltene is carried out by using high temperature and high pressure closed system. During asphaltene pyrolysis, the amount of methane is constantly increased but those of ethane, propane, and butane + pentane are all first increased and then decreased and eventually go to zero with the increase of the experiment temperature. And the dynamic parameters of gaseous hydrocarbon generation can be used to analyze the dynamic procedure of the asphaltene pyrolysis at the geological scale. The experimental results can perfect the theory of the origin of natural gas and provide an evidence for source judgment and resource evaluation of natural gas in marine strata in China. [ABSTRACT FROM AUTHOR]

The faults that developed in the Liaoxi Depression can be classified into three types according to their extent and connectivity with the source and reservoir rocks (i.e. type I faults, type II faults and type III faults). These faults played different roles in controlling the basin geomorphology; the formation and evolution of the source rocks, reservoir rocks, cap rocks and traps; and the migration and accumulation of hydrocarbons in the Liaoxi Depression. Extending from the basement to the Neogene strata, type I faults, which are the largest in the basin, mainly controlled the development and basin-scale geomorphology; type II faults mainly controlled the sub-tectonic zones; and type III faults mainly controlled the formation and evolution of the traps. The movements of type I and type II faults during the hydrocarbon expulsion period were closely related to oil and gas migration. The rates of fault activity varied among the different sags of the Liaoxi Depression. Type I faults in both the northern and southern sags appear to have moved considerably during the hydrocarbon generation and expulsion stages, which strongly promoted hydrocarbon migration, whereas weakly active type I faults in the central sag made limited contributions to hydrocarbon migration. The sealing behaviour of the faults controlled the hydrocarbon migration directions and locations, and the good lateral sealing ability of the type I faults in the northern and southern sags confined the accumulation of hydrocarbons within the sags independently. However, the type I faults in the central sag partially opened laterally, which increased the likelihood of hydrocarbon migration from the sag centre to the uplift and reduced the likelihood of hydrocarbon accumulation within the sag centre. Therefore, the oil- and gas-enrichment patterns in the Liaoxi Depression are closely related to the characteristics of the faults, with traps near types I and II faults showing an increased likelihood of oil- and gas-field formation, as observed with the JZ9-3, LD4-2 and LD5-2 wells, and traps located in the sags remote from types I and II faults showing a reduced likelihood of oil and gas accumulation. [ABSTRACT FROM PUBLISHER]

A new brominated polyacetylene, xestonariene I (1), along with three known related analogues (2–4), was obtained from Chinese marine spongeXestospongia testudinaria. Its structure was determined on the basis of detailed spectroscopic analysis and by comparison with literature data. Compound4exhibited significant inhibitory activity against pancreatic lipase, which plays a key role in preventing obesity, with an IC50value of 0.61 μM, being comparable to that of the positive control orlistat (IC50 = 0.78 μM). [ABSTRACT FROM PUBLISHER]

The different agreements on oil and natural gas signed by Russian and Chinese companies testify to the profound changes in the oil and gas policies of both Russia and China. We stress the importance of the contractual norms which structure the energy interdependency of the countries involved. As there is no international multilateral framework able to manage energy supply security, the way the countries involved construct their energy interdependence to an extent defines models of sectoral governance. [ABSTRACT FROM PUBLISHER]

The Chipu Mississippi Valley-type (MVT) deposit is located on the southwest (SW) margin of the Sichuan Basin. Occurrence of plentiful organic matter (bitumen) at this deposit and abundant hydrocarbon reservoirs in the SW Sichuan Basin implies a link between lead–zinc mineralization and hydrocarbon systems in this area. The high δ34S values of most metal sulphides from the different ore stages suggest that H2S-bearing gases and/or thermochemical sulphate reduction (TSR) by organic matter could have been the source of reduced sulphur involved in ore formation. Sulphides with small positive to negative δ34S values can be attributed to organically bound sulphur at the Chipu deposit. Carbon and oxygen isotopic compositions from sparry carbonates suggest mixing of organic carbon with seawater-derived carbon in the mineralization process. From the early to the later ore stages, δ13CPDBvalues of ore-hosting carbonates are increasingly more negative, which indicates strengthening of the TSR role during mineralization. Hydrogen and oxygen isotopes in fluid inclusions in the quartz gangue indicate the provenance of the ore-forming fluids in the hydrocarbons. Moreover, some extremely low hydrogen isotope values suggest the addition of hydrogen from the same source. The low H/C ratios and high non-hydrocarbon component of the bitumen (Zhanget al. 2010) also suggest that the organic matter may have been involved in TSR and subjected to a strong oxidation by ore-bearing fluids. This study attempts to explain the lead–zinc mineralization process and the role of organic matter in it. As there is a demonstrable relationship between the evolution of the hydrocarbons and regional lead–zinc mineralization along the SW edge of the Sichuan Basin, we propose a possible model in which the MVT mineralization coincided with the degradation of hydrocarbon reservoirs due to the large-scale migration of basinal fluids, most likely driven by the late Indosinian orogeny in response to the closure of the Palaeo-Tethys Ocean. [ABSTRACT FROM AUTHOR]

Two new dibenzocyclooctadiene lignans, schinegllignans A and B (1 and 2), together with 11 known (3-13) were isolated from the fruit of Schisandra neglecta. Their structures and stereochemistries were elucidated by spectroscopic methods, including 1D, 2D NMR, and HR-ESI-MS techniques. Compounds 1 and 2 were evaluated for their anti-HIV activities, and they showed moderate anti-HIV-1 activities with therapeutic index values of 18.5 and 24.6. [ABSTRACT FROM AUTHOR]

Three new polyoxygenated cyclohexenes, named uvacanols F, G, H (1-3), were isolated from the roots of Uvaria calamistrata (Annonaceae). Their structures were determined to be 2-acetoxyl-5-chlorine-benzoyloxymethylcyclohex-1 (6)-ene-4-ol-3-benzoate (1), benzoyloxy-methylcyclohex-1 (6)-ene-2,3,4-triols-5-benzoate (2), 3-acetoxyl-benzoyloxymethylcyclohex-1 (6)-ene-4,5-diols-2-benzoate (3) by spectroscopic methods and chemical derivatization. [ABSTRACT FROM AUTHOR]

To understand the hydrocarbon emissions in China, the source profile and emission factors of hydrocarbon species from cooking sources were measured. The measured commercial restaurants represented Sichuan cuisine, Zhejiang cuisine, household-style cuisine and Korean-style barbecue, respectively. Forty-one hydrocarbon species were quantified, in which the abundant species were n-butane, iso-butane, 2-methlybutane, pentane, propene, 1-butene, toluene and benzene. The hydrocarbon mixing ratios from Korean barbecue were evidently higher than those from the other Chinese-style restaurants, and the Sichuan-style restaurants had significantly higher emissions of iso-butane and d-limonene. The hydrocarbon source profiles of Chinese cooking were different from the profiles obtained from cooking sources of other cities. While the Korean-style barbecue had abundant species such as light alkanes, propene, benzene and toluene, similar to results for Western barbecue source, the relative percentages of these species were different, probably due to the difference in fuels for cooking. The hydrocarbon emission factors were estimated for Sichuan-style cuisine, which was 0.21g hydrocarbon per kg of meat cooked, much lower than that from the barbecue source. [ABSTRACT FROM AUTHOR]

Since the 1990s China has been undergoing an energy transition. Increasing dependence on foreign hydrocarbons is the transformation's most striking feature, leading much analysis of China's energy system toward geo-strategic studies. This article analyses a) the features defining the transition - not exclusively dependence on foreign oil markets - highlighting continuities and ruptures with tradition; and b) relations between the transformation and three elements of China's current development phase: i) strong growth and changing industrial specialisation, ii) transport expansion and iii) urbanisation and new consumption habits. If these elements are indeed drivers, and if they persist, current features of the transition (including growing dependence on external markets) will continue. [ABSTRACT FROM AUTHOR]

Spatial distribution, composition and possible source of 10 parent polycyclic aromatic hydrocarbons (PAHs) in littoral surface sediments from the Yellow Sea were investigated. The total PAHs concentrations varied from 12.4 to 8294.0 μg/kg dry weights, and the sites with the highest levels were all located in Dalian Bay. At most sampling sites, PAH components with moderate and high molecular weights were dominant, while percentage of low molecular weight species was higher at a few sites close to several harbor cities. The specific ratios of paired PAH isomeric compounds for source apportionment suggested that various pyrolytic procedures were the major origin in the Yellow Sea, whereas petrogenic cause only occurred at a small number of the monitoring sites. The averaged effect rang low (ERL) quotient for the studied PAH components was generally below the threshold value of 1.0 in most sea areas, indicated that the potential ecological risks of PAHs contamination in surface sediments were normally not high in the Yellow Sea, however, the situation in Dalian Bay should be cautioned due to the high mean ERL quotient. [ABSTRACT FROM AUTHOR]

Airborne particulates were collected in nine size fractions by using Andersen low-volume air samplers in the cities of Shenyang, Fushun, and Tieling, Liaoning Province, in northeast China, during the period from July 2001 through December 2003. Nine polycyclic aromatic hydrocarbons (PAHs) and seven nitropolycyclic aromatic hydrocarbons (NPAHs) in the airborne particulates were determined. The mean concentrations of the sums of the nine PAHs and seven NPAHs were highest in Fushun, which is an industrial city, and lowest in Shenyang, which is a commercial city, although the consumption of petroleum and coal were largest in Shenyang. The nine fractions were grouped into three groups: > 7 μ m, 2.1-7 μ m and < 2.1 μ m. In each city, more than 50% of the total PAHs and total NPAHs were found in the fine particulate fraction (< 2.1 μ m). In each city, all PAHs and all NPAHs were clearly higher in winter than in summer. The concentration ratio of 1-nitropyrene to pyrene, which is a suitable indicator to identify diesel engine and coal combustion as proposed by our previous study, showed that the major contributors of PAHs and NPAHs in the airborne particulates were coal-combustion systems both in summer and winter in Fushun and Tieling. In Shenyang, atmospheric PAHs and NPAHs also seemed to be affected by coal combustion systems in winter, whereas gasoline engine vehicles seemed to be a major contributor in summer by the larger concentration ratio of 1-nitropyrene to pyrene. Cluster analysis and other diagnostic ratios such as benz[a]anthracene to chrysene, benzo[ghi]perylene to benzo[a]pyrene supported these results. [ABSTRACT FROM AUTHOR]

The Songhuajiang River watershed is the important industrial and foodstuff base in the northeast part of China. However, the increasing population, industrial and agricultural activities around the Songhuajiang River lead to the introduction of contaminants and the possibility of polluting the river. This investigation represents an extensive study of the spatial and temporal distribution of polycyclic aromatic hydrocarbons (PAHs) in the sediment samples collected from the Songhuajing River in flood season (August, 2005) and icebound season (December, 2005) by using the gas chromatography-mass spectrometry (GC/MS) analyses. In flood season, the total PAHs concentrations in sediments ranged from 84.44 ng g-1 to 14938.73 ng g-1, with average concentration of 2430.37 ng g-1. In icebound season, the total PAHs concentrations in sediments ranged from 23.61 ng g-1 to 15310.25 ng g-1, with average concentration of 1825.60 ng g-1. Compared to the concentration of PAHs between central sediment and riverbank-exposed sediment at some stations, the concentration in exposed sediment was higher than that in the central sediment in the upstream of river. It was also observed that the concentration of PAHs in flood season was higher than that in icebound season. The level of PAHs in the sediments of Songhua River was higher in comparison with values reported from other river and marine systems in the world. The most contaminated sediment samples were found in the upstream area of Songhuajiang River located near Jilin petrochemical industrial company for both flood and icebound seasons. The 4–6 ring PAHs were dominated in sediments due to their higher persistence. There was positive correlation between total PAHs concentration in sediment samples and TOC or LOI (r = 0.62 and r = 0.58, P < 0.01, n = 31). The calculated ratio of selected PAH and principal component analysis (PCA) suggests the contamination source of PAHs were combined inputs of pyrolytic and petrogenic contamination, due to the discharge from municipal and industrial wastewater runoff and atmospheric fallout. [ABSTRACT FROM AUTHOR]

Experiments have been carried out to investigate the effects of operating parameters and coal types on the formation of HCN and NH[SUB3] during coal pyrolysis in a fixed-bed reactor system with temperature-programmed heating. Three coals from China and 2 coals from Australia, ranging in ranks from bituminous coal to anthracite, were used in these experiments. Our experimental results indicate that the formation of HCN and NH[SUB3] is affected by peak temperature, particle size, and gas flow rate. The effects of these operating parameters vary with the coal properties. In addition to coal rank, the petrographic composition and/or geographic origin of the coal are important factors influencing the formation of HCN and NH[SUB3] during pyrolysis. [ABSTRACT FROM AUTHOR]