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High‐pressure hydrogen direct injection technology can enable an internal combustion engine to attain high thermal efficiency and discharge clean emissions; hence, the advantages provided by hydrogen jet impingement are crucial. This paper presents an experimental investigation of the high‐pressure hydrogen direct injection from a single‐hole cylindrical injector. A test rig with a spring set was designed based on the impulse conservation law to test important high‐pressure hydrogen jet impingement parameters, such as jet impingement force and impulse. The results show that the hydrogen gas jet exhibits a two‐zone behavior. In Zone I (near‐field dynamic region), the jet impulse is not conservative, and the jet characteristic parameters (jet impingement force and impulse) fluctuate—first decreasing and then increasing. In Zone II, the jet impulse is conservative. This two‐zone jet feature is induced by shockwaves because a high‐pressure hydrogen jet with a high nozzle pressure ratio reaches its sonic speed at the nozzle outlet. The Mach disk height is the inflection point of these two zones. Moreover, the hydrogen injection pressure has a considerable influence on the gas jet. As the injection pressure increases, the hydrogen jet impingement force and impulse increase. Both jet parameters have a linearly increasing relationship with injection pressure. [ABSTRACT FROM AUTHOR]

The coupling of Eulerian and Lagrangian methods in the Eulerian–Lagrangian Spray Atomization (ELSA) approach is critical. This study proposes an equation for the primary breakup particle diameter D of a diesel fuel spray and adopts it as a key transition criterion for coupling. A three-dimensional diesel spray is modeled by the large-eddy simulation (LES) approach. This improved ELSA simulation was conducted using various transition criteria for particle diameter Dcr. The results show that fuel spray experiences two stages: stage I, when a liquid column appears without a dispersed phase, and stage II, when primary breakup occurs with many discrete particles. Although Dcr has little influence on the macro-spray characteristics, such as top penetration distance S and spray cone angle θ, it has significant effects on discrete particles, such as their number, average diameter, distribution and location, and spray cone area. Dcr should be determined on the basis of actual operating conditions. [ABSTRACT FROM AUTHOR]

The Permian mafic dykes of Santanghu Basin offer an opportunity to study the nature of mantle source and tectonic setting of the basin, as well as to provide the theoretical basis for structural transformation of East Junggar region. In this study, zircon U–Pb geochronology, mineral composition analysis, whole‐rock elemental, and Sr‐Nd isotopic geochemistry were conducted to explore the origin and evolution of the primitive magma. LA‐ICPMS zircon U–Pb dating yields ages at 269 Ma. The elemental geochemistry results suggest enrichments in Ba, Pb, and Sr but depletions in Nb, Ta, Zr, and Hf, which indicate that the magma source was influenced by fluid metasomatism. All samples show moderate initial Sr‐Nd isotope results ((87Sr/86Sr)I = 0.704299 to 0.704490 and εNd(t) = +6.16 to +6.83) and have high Sm/Yb ratios, which suggest that the diabases were derived from partial melting of 5%–7% spinel‐garnet Iherzolite lithospheric mantle. Combined with petrological, geochronological data, and the regional tectonic background, it is interpreted that the diabases from Santanghu Basin originated from lithospheric mantle metasomatized by subduction fluids under the background of intracontinental extension. [ABSTRACT FROM AUTHOR]

The Ordos Basin is a large depression-type lake basin in the late Triassic. Here, we present a study on Yufenites, which were found in the BWZ (BaWangZhuang) section, TNH (TangNiHe) section and Well Z11 in the Tongchuan area on the southern margin of the basin and in the lower shale layer of Chang 7 member in Triassic Yanchang Formation. Yufenites are slightly flattened spindle-shaped fossils, pointed and thin, with obvious spiral patterns on the surface. The spiral starts from the thin part and turns from right to left, and the pitch changes from narrow to wide. The Yufenites contains animal and plant residues that have not been completely digested, and a large number of mineral aggregates that formed around phosphorus-containing dolomite as a growth base. Yufenites had a high viscosity and strength when discharged. Due to the action of microorganisms, the diagenesis of Yufenites occurs earlier and faster than that of the surrounding rocks. Based on this description, we believe that this Yufenites is from a large carnivorous fish. In the Late Triassic, humid and hot climatic conditions, low water kinetic energy, desalinated water, high productivity, magmatic-hydrothermal activity and other factors played an important role in the preservation of Yufenites. [ABSTRACT FROM AUTHOR]

To investigate primary breakup close to an injector, this paper presents both experimental and numerical research on high-pressure common-rail diesel injection. We propose a new method named SD-ELSA model to realize automatically identifying droplet features for high-pressure diesel spray based on the classic ELSA (Eulerian Lagrangian Spray Atomization) model; this method is suitable for varied injection operation conditions. The SD-ELSA first identifies the liquid bulk due to breakup of the continuous phase in near field, and then converts the Eulerian liquid bulk into Lagrangian particles to complete the calculation of the total spray atomization. The SD-ELSA model adopts two key criteria, i.e., the sphericity (S) and the particle diameter (D); the qualified liquid mass is transformed into Lagrangian particle, realizing the coupling of the Eulerian–Lagrangian model. The SD-ELSA model illustrates the total diesel spray atomization process from the breakup liquid column to the droplets. [ABSTRACT FROM AUTHOR]

Abstract: The eastern part of the Central Tianshan Belt in China is characterized by abundant granitoids, which are not only indicators of the interaction between crust and mantle but also can be used for tracking the tectonic evolutionary history of the orogen. Four granitic plutons, muscovite granites (MG), biotite monzonitic granites (BMG), biotite granites (BG), and alkali granites (AG), have been recognized to have intruded in the Mishigou area, Central Tianshan Belt. The MG has pronounced a S-type affinity, which is strongly peraluminous with a high aluminum saturation index, and displays positive Rb, Th, U and LREE anomalies with a strong negative Ba, Nb, Sr, P, Ti and Eu anomalies. Therefore, the magma of the MG is considered to have been derived from melting of thickened continental crust, which is composed mainly of the sediments eroded from a pre-Silurian continental island-arc. The U–Pb zircon age of 424.5±2.6Ma constrains the age of MG and crust thickening. The BG and BMG granitoids display I-type geochemical features and have affinities to subduction arcs. Both of them are characterized by calc-alkaline peraluminous granites with a significant LREE enrichment and a negative Eu anomaly, as well as a depletion in Ba, Nb, Ta, Sr, P and Ti and an enrichment in Rb, Th, U, Nd, Zr and Sm. These characteristics indicate that they were derived from a mixed magma source between lower continental crust and the input of components derived from the mantle wedge above the subduction zone. The LA-ICPMS zircon U–Pb ages of 411±4.7Ma and 402±3.4Ma represent the formation ages of the BG and BMG granitoids, respectively, which also constrain that the subduction of the South Tianshan oceanic crust also occurred during Early Devonian time. The AG shows a typical A-type granite affinity with depletion of Nb, Ta, Sr, P, Ti and Y. It is interpreted that AG was formed in a within-plate tectonic setting, and related to continental up-doming and rifting zones as a consequence of the extensional collapse after the collision of the Tianshan orogen. The U–Pb zircon age of 290±5.1Ma represents the formation age of the AG, and the time of the extensional collapse and rifting. [Copyright &y& Elsevier]

Reports the zircon ion microprobe (SHRIMP) dating results for Songshugou garnet pyroxenite and Fushui gabbro. Suggestion that the Fushui gabbro-diorite complex body possesses characters of Alaska-type island-arc mafic-ultramafic plutonic complex which is an important component of the island-arc magmatic belt; Kinds of rocks that constructed the Early Paleozoic tectonic pattern of plate subduction and collision; Implications for the understanding of the tectonic evolution of the Qinling Orogenic Belt.

The chemistry of the basic volcanic rocks at the south margin of the Qinling orogenic belt (SMQOB) suggests that they were formed in an intraplate tectonic setting. The REE distribution patterns show these rocks are strongly enriched in LREE with high ΣREE, and their trace elements geochemistry is similar to that of continental flood basalt. All the above evidence suggests that the Caledonian basic volcanic rocks in the SMQOB were tholeiitic basalts formed in an intraplate spreading-initial rift tectonic setting. The characteristics of regional geology and geochemistry indicate that there was an intraplate spreading-rift tectonic setting between the South Qinling block and the Yangtze block in the Caledonian epoch. The dynamic spreading in this district began in the Early Caledonian and then the intraplate spreading-initial rifts were formed in the late Caledonian. As a result of spreading of the Tethys and geodynamic processes in deep mantle, the Mianlue-Huashan oceanic basin was formed between the Qinling block and the Yangtze block in Devonian, and the Qinling microplate was separated from the northern part of the Yangtze plate. [ABSTRACT FROM AUTHOR]

The article focuses on findings of a study on geochemical characteristics and geological significance of picritic rocks in Permian Tiaohu Formation from Santanghu Basin, Xinjiang of China. Topics include magmatic activity of Permian in Santanghu Basin; characteristics of picritic rocks, such as SiO2 amount of picritic rocks; and voluminous postcollisional granitoids and Armantai and Karamaili suture zone formation age.

Shales in the middle Permian Lucaogou Formation in the intracontinental Santanghu rift basin have been considered as “typical” organic-rich profundal shales for decades. Our study of well cores using petrographic microscope and scanning electron microscopy suggests an otherwise complex hydrovolcanic and hydrothermal origin. This paper describes characteristics of a particular type of the shales, composed of fine-grained detrital minerals and lithic grains. Some of them are orthopyroxene, calcite, peralkaline feldspars, and analcime that are interpreted as derived from peralkaline-alkaline carbonatite, pyroxenite, analcime phonolite, and andesite, whereas others are quartz, dolomite, ankerite, serpentine, and calcite that were precipitated from syndepositional or penecontemporary hydrothermal fluids. Grain size ranges from 0.001 to 2 mm, mostly 0.01–0.1 mm. Well-developed laminae are mostly 0.5–3 mm thick and alternate with tuffaceous dolomicrite. The rocks are interpreted as sublacustrine hydrovolcanic deposits, which had been altered by syndepositional hydrothermal fluids. The interpretation is substantiated by abundant cone-shaped stratigraphic buildups on seismic sections in the basin. This study shows an ancient example of volcanic-hydrothermal deposits in a rift basin. [ABSTRACT FROM AUTHOR]

The Maoniushan Formation in the northern part of the North Qaidam Orogen (NQO), NW China, contains key information on a Paleozoic change in tectonic setting of the NQO from compression to extension. Here, new zircon U–Pb, petrological, and sedimentological data for the lower molasse sequence of the Maoniushan Formation are used to constrain the timing of this tectonic transition. Detrital zircons yield U–Pb ages of 3.3–0.4 Ga with major populations at 0.53–0.4, 1.0–0.56, 2.5–1.0, and 3.3–2.5 Ga. The maximum depositional age of the Maoniushan Formation is well constrained by a youngest detrital zircon age of ∼409 Ma. Comparing these dates with geochronological data for the region indicates that Proterozoic–Paleozoic zircons were derived mainly from the NQO as well as the Oulongbuluk and Qaidam blocks, whereas Archean zircons were probably derived from the Oulongbuluk Block and the Tarim Craton. The ∼924, ∼463, and ∼439 Ma tectonothermal events recorded in this region indicate that the NQO was involved in the early Neoproterozoic assembly of Rodinia and early Paleozoic microcontinental convergence. A regional angular unconformity between Devonian and pre-Devonian strata within the NQO suggests a period of strong mountain building between the Oulongbuluk and Qaidam blocks during the Silurian, whereas an Early Devonian post-orogenic molasse, evidence of extensional collapse, and Middle to Late Devonian bimodal volcanic rocks and Carboniferous marine carbonate rocks clearly reflect long-lived tectonic extension. Based on these results and the regional geology, we suggest that the Devonian volcano-sedimentary rocks within the NQO were formed in a post-orogenic extensional setting similar to that of the East Kunlun Orogen, indicating that a major tectonic transition from compression to extension in these two orogens probably commenced in the Early Devonian. [ABSTRACT FROM AUTHOR]

Tuffs, produced by explosive volcanic eruptions, are widely deposited throughout the Precambrian to Cenozoic stratigraphic record. Due to rapid compaction and erosion, preservation and identification of tuffs in distal environments are challenging. However, in deep lacustrine environments, tuffs may be found well-preserved as interlayers in the organic-rich mudstone. This in turn provides valuable insights into the origin, transport, and diagenesis of volcanic material. In this study, we performed an integrated sedimentological, mineralogical, and geochemical analysis of seven tuff samples collected from the lower part of the Chang7 member of the Maquan section to infer on their provenance, transport mechanisms and post-depositional alterations. Immobile element ratios, tectonic discrimination diagrams, trace element distribution patterns, and negative whole-rock εNd(t) reveal an intermediate to felsic continental arc source of the studied tuff. Supported frameworks and ash aggregates in the tuff are in favor of the transport from pyroclastic density currents and ash plumes during multiple volcanic eruptions with various degrees of eruption volume and water content. Tuff diagenesis is characterized by dissolution of plagioclase, illitization of smectite, cementation of carbonate minerals, and presence of buddingtonite. Relatively ordered illite-smectite and low vitrinite reflectance from the adjacent organic-rich mudstone indicate diagenetic evolution of studied tuff have reached mesogenetic stage. • The tuffs of Chang7 member originated from felsic magmas at continental-arc setting. • The tuffs were transported by pyroclastic density current and ash plumes with various eruption volume and water content. • The tuffs have evolved to mesogenetic stage. [ABSTRACT FROM AUTHOR]

The Chang 7 oil shales of the Triassic Yanchang Formation in the southern margin of the Ordos Basin has been a concern of researchers because of the extensive development of lacustrine hydrothermal sedimentary rocks in it. Here, we studied the petrological and mineralogical characteristics of hydrothermal sedimentary rocks through ordinary thin sections, scanning electron microscope and electron probe observations, and evidences about hydrothermal activity were identified from the oil shales. On this basis, we further complete their geochemical analysis. The results show that the Cs, U, Th, Pb, and Mn of the Chang 7 oil shale have significant positive anomalies and that the Eu and Ta elements have negative anomalies. The TOC value of Chang 7 oil shale ranges from 0.18 wt% to 18.15 wt%, with an average value of 3.85 wt%. The average value of the Chang7-3 section is 5.33 wt%, the average value of the Chang7-2 section is 2.15 wt%, and the average value of the Chang7-1 is 3.05 wt%. In addition, the hydrothermal index of Chang 7 source rock shows: The correlation coefficient between the hydrothermal index and the TOC content is as high as −0.86 and 0.85. There is the most hydrothermal input in Chang7-3 deposition period, it was somewhat weakened in the Chang 7-2 deposition period, and it was enhanced in the Chang 7-1 deposition period. Hydrothermal deposition is involved in the hydrocarbon generation of oil shales. The greater the hydrothermal input intensity is, the greater the TOC content of the oil shale is. [Display omitted] • A variety of hydrothermal minerals and mineral combinations have been identified from black shale. • The influence of hydrothermal activity on Chang 7 oil shale was studied from the perspective of element geochemistry. • Longitudinal analysis of the relationship between drilling fluid input and organic matter abundance. [ABSTRACT FROM AUTHOR]

Lacustrine organic-rich shale (LORS) developed in the Chang 7–3 section of the Triassic Yanchang Formation in the Ordos Basin. LORS has been proven to be a source of crude oil and tight oil, as well as a source and reservoir for shale oil in the basin. A total of 35 LORS samples were collected from Well Z233 and analysed by mineralogy and element geochemistry to reveal the characteristics and controlling factors of LORS. The following results were obtained: ① In the oil shale, the organic matter is composed of type I and type II kerogen, with a predominance of type II. The organic matter is mature and reaches high levels of abundance. ②Through further analysis. The values of w(U)/w(Th), w(V)/w(Cr), w(Ni)/w(Co), the size and morphology of pyrite, indicates that the lake water of the LORS deposition period in the study area is anoxic or suboxic state. the TOC of the samples was found to have significant positive correlations with the w(Mo) and w(Ba bio) contents. Paleoproductivity can be inferred to be the key factor controlling organic matter enrichment in the LORS. ③Volcanic and hydrothermal activities promote the development of LORS, provide nutrients needed by organisms, promote the growth of organisms, and improve paleoproductivity. Hydrothermal activity leads to the formation of an anoxic environment at the bottom of the lake, and tuff will cover the sediments, which promotes LORS preservation. This study reveals in detail paleoproductivity is the main factor in the formation of LORS during the evolution of the basin. Volcanic and hydrothermal activities promoted the increase of paleoproductivity, and finally the oil shale layers with the richest organic matter have been formed. And thereby deepens our theoretical understanding of organic matter enrichment. • The organic matter types of oil shale are type I and type II, with type II being the main type. • The redox and paleoproductivity conditions for the development of Chang 7 LORS were analyzed. • It is believed that paleoproductivity is the key factor controlling the accumulation of organic matter in the study area. • The influence of volcanic and hydrothermal activity on LORS is analyzed. [ABSTRACT FROM AUTHOR]

Dual-fuel diesel/natural gas direct-injection engine is promising and highly attractive due to its low-carbon emission and high thermal efficiency, and both high-pressure diesel and natural gas injections are critical for air-fuel mixing. This study presents an optical experimental investigation on the high-pressure dual-fuel diesel/methane injection process based on a constant-volume vessel test rig. The results show that the diesel penetration process of the dual-fuel injection experiences two stages: Stage I, the diesel tip penetration S diesel , the diesel spray area A diesel , and the diesel spray perimeter C diesel of the dual-fuel injection are smaller than those of the single diesel injection. Stage II, both the diesel and methane continue to penetrate forward, and S diesel , A diesel , and C diesel of the dual-fuel injection become larger than those of the single diesel injection do. The diesel injection pressure causes effect on the dual-fuel spray penetration. The diesel injection pressure directly causes linear influence on the two-stage dual-fuel injection characteristic. As the diesel injection pressure increases, the diesel spray meets the methane jet advancer and the cross point occurs linearly earlier. Furthermore, the dual-fuel injection is asymmetric and the methane gas jet enhances this asymmetry so that the spray cone shifts to the side of the methane gas jet., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)