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Tight gas is the fastest developing unconventional natural gas resource, becoming the principal part for gas reserves and production growth in China. The Sulige gas field is the largest gas field and also the typical low porosity and low permeability tight sandstone gas field discovered in China, with an annual natural gas output exceeding 300 billion and cumulative output exceeding 290 billion, playing an important role in ensuring national energy provision, helping China’s energy transformation, and promoting green, low-carbon, environmental protection and high-quality development. Based on sample collection and laboratory analysis, natural gas compositions including hydrocarbons, non-hydrocarbons, light hydrocarbons, and noble gases of the Sulige gas field are systematically analyzed, their genetic identifications are identified, and finally gas source originations and contribution proportions are comprehensively discussed from the perspectives of noble gases and hydrocarbon gases. The main achievements are as follows: 1) natural gases in the Sulige gas field are mainly alkane gases, with high methane content, high drying coefficient, low heavy hydrocarbon contents, low non-hydrocarbon gas contents of CO2 and N2, and relatively low noble gas contents. The helium content is relative 2 order of magnitude higher than the atmospheric value, while neon, argon, krypton, and xenon are relatively about 1–2 orders of magnitudes lower than the atmospheric values. 2) The carbon and hydrogen isotopes of alkanes are generally positive sequence distributions with some part inversion. The 3He/4He values are mainly distributed in magnitude of 10−8, the 40Ar/36Ar is ranged from 506 to 1940, the 129Xe is relative loss, and the 132Xe is relative surplus. 3) Natural gases in the Sulige gas field are typical coal-formed gases generated from a humic organic mother material with maturity from high mature to over mature according to C7 and C8 light hydrocarbons and alkane carbon isotopes. Noble gases are typical crustal genesis, mainly originating from the radioactive decay of crustal source materials. 4) The gas source correlations of noble gases and alkane gases and their quantitative evaluations on source contributions show that natural gases in the Sulige gas field are originated from Carboniferous-Permian coal measure source rocks in Ordos Basin, mainly contributed by coals and supplemented by mudstones, accounting for 55–60% and 40–45%, respectively.

Natural gases in China are mainly coal-derived gas, with assistance from oil-typed gas. At present, many genetic identification methods, from hydrocarbon composition and isotope to light hydrocarbon and biomarker indexes, have been formed, but combined methods from non-hydrocarbon gases are lacking. Based on compositions and isotopes geochemical characteristics and the differences of non-hydrocarbon nitrogen gas in coal-derived gas and oil-typed gas, and combining the isotopic geochemical characteristics of non-hydrocarbon helium, the comprehensive identification methods of coal-derived gas and oil-typed gas for hydrocarbon gases according to the associated non-hydrocarbon gases of nitrogen and helium are established and the preliminary applications have been engaged. The main recognitions are as follows:1)Coal-derived gas generally has relatively lower nitrogen abundance, mainly distributed from 0 to 31.2% with main frequency from 0 to 2%. Oil-typed gas, on the other hand, usually has relatively higher nitrogen abundance, mainly distributed from 1.1 to 57.1% with main frequency from 2 to 16%. 2) Coal-derived gas generally has relatively heavier nitrogen isotope values, mainly distributed from -8 to 19.3‰ with main frequency from -8 to 8‰.Oil-typed gas usually has relatively lower nitrogen isotope values, mainly distributed from -10.6 to 4.6‰ with main frequency from -8 to 4‰.3)The geochemical characteristic differences of coal-derived gas and oil-typed gas are mainly due to the fact that the sapropel parent material is relatively rich in nitrogen element and rich in light δ14N, while the humic parent material is relatively poor in nitrogen element and rich in heavy δ15N. The differences on thermal maturity of source rocks, the redox conditions of source rock sedimentary environment, and the salinity of water body are also important effective factors.4)Differences on nitrogen abundances and isotopes in coal-derived gas and oil-typed gas have great significance in genetic identification. The genetic identification chart of R/Ra-δ15N for organic and inorganic nitrogen in natural gas and the comprehensive joint identification charts of R/Ra-δ15N-N2 of nitrogen and helium for coal-derived gas and oil-typed gas have been established, and are of great reference in investigating the origins and sources of natural gas and guiding natural gas exploration in China.

In this work, Mo[O.sub.2]@NPGA nanocomposites were successfully prepared via a simple hydrothermal and calcination route. The as-prepared Mo[O.sub.2]@NPGA composites exhibit a synergistic effect between Mo[O.sub.2] and N,P-codoped graphene aerogels, which can significantly improve the electrochemical performance of the Mo[O.sub.2]@NPGA electrodes. Moreover, the results also proved that the mass loading of Mo[O.sub.2] has a huge effect on the electrochemical properties of Mo[O.sub.2]@NPGA composites. With an appropriate amount of Mo[O.sub.2], the Mo[O.sub.2]@NPGA composite shows a high specific capacitance (335 F [g.sub.-1] at 1A [g.sub.-1]) and excellent cycle stability (capacitance remains at 88% after 6000 cycles). Furthermore, the assembled symmetric supercapacitor displays a high energy density of 23.75 W h [kg.sub.-1] at a power density of 300 W [kg.sub.-1] and can maintain an energy density of 17.1 W h [kg.sub.-1] when the power density reaches up to 6005 W [kg.sub.-1]. Key words: supercapacitor, Mo[O.sub.2], NP-codoped graphene aerogels, nanocomposite. Dans le cadre des presents travaux, nous avons prepare des nanocomposites de Mo[O.sub.2] avec des aerogels de graphene codopes a l'azote et au phosphore (Mo[O.sub.2]@NPGA) par une methode hydrothermique simple suivie d'une calcination. Ces composites Mo[O.sub.2]@NPGA tels que nous les avons prepares montrent un effet synergique entre le Mo[O.sub.2] et les aerogels de graphene codopes a l'azote et au phosphore (NPGA) permettant d'ameliorer de facon significative la performance electrochimique des electrodes de Mo[O.sub.2]@NPGA. De plus, les resultats ont egalement permis de demontrer que la charge en masse de Mo[O.sub.2] influence enormement les proprietes electrochimiques des composites de Mo[O.sub.2]@NPGA. Lorsqu'il contient une quantite appropriee de Mo[O.sub.2], le composite Mo[O.sub.2]@NPGA montre une capacitance specifique elevee (335 F*[g.sup.1] a1A [g.sup.1]) et une excellente stabilite de cycle (il conserve une capacitance de 88 % apres 6 000 cycles). En outre, le supercondensateur symetrique assemble a partir de ce materiau presente une densite energetique elevee, soit 23,75 W h [kg.sup.1], a une densite de puissance de 300 W [kg.sup.1] et il peut maintenir une densite energetique de 17,1 W h [kg.sup.1] jusqu'a une densite de puissance atteignant 6 005 W [kg.sup.1]. [Traduit par la Redaction] Mots-cles: supercondensateur, Mo[O.sub.2], aerogels de graphene codopes a l'azote et au phosphore, nanocomposite., Introduction In respond to the problem caused by the economic booming and instant energy supply, superior energy storage devices are urgently needed. (1,2) Supercapacitors are one of the most promising [...]