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Shale oil has become a popular topic for global, unconventional oil and gas research in the petroleum, industry. Recent exploration efforts have indicated that, laminar carbonates are closely related to the favorable, depositional strata of lacustrine shale oil. This research, focused on inter-bedded layers of laminar carbonates as, well as mudstone and shale in the Dongying depression of, the Bohai Bay Basin in eastern China, and attempted to, reveal the genesis and evolution of the carbonates by, petrological analyses. The results demonstrated that: the, carbonates could be categorized into two groups,, crystalline carbonates and micritic carbonates; the, crystalline carbonates were well crystallized and greenish, under fluorescent light; and the micritic carbonates were, not well crystallized and had biotic textures. It was, discovered that the crystalline carbonates were mainly, developed in the shale layer and were formed from the, late-filling effects of the diagenetic cracks along the shale, fissility planes. The micritic carbonates were formed from, direct deposition controlled by biological effects in the, stratified flows of the seasonal lake basins. There are five, main lithofacies in the study layers, which are as follows:, LF1: thin lenticular laminae of crystalline carbonates, LF2:, laminae of micritic carbonates, LF3: thick massive lime, mudstone, LF4: massive mudstone, LF5: black shale., There are two shale oil accumulation models; one model, commonly appears in LF4 and LF5 and is called, 'selfgeneration and self-reservoir; the other model, commonly appears in LF1 and is called the crystalline, carbonate reservoir. Thus, the favorable lithofacies, (assemblages) for shale oil accumulation are LF1, LF4 and, LF5. In the petroleum industry, crystalline carbonates, form 'sweet spots', which are most beneficial for shale oil, accumulation and production., Open-Access Online Publication: March 03, 2023

In order to construct the dominant population of rice under dry cultivation, the external characteristics of the population and the photosynthetic physiological characteristics of the upper three leaves were investigated. In this study, a double factor interaction method of seeding rate and nitrogen rate was used to construct the dominant population of rice under dry cultivation. We determined 195 kg·ha-1 seeding rate and 140 kg·ha-1 nitrogen rate as the appropriate configuration. To achieve high yield, high nitrogen utilization and moderate morphological characteristics by coordinating the comprehensive advantages of population spike number and spike grain number, and to increase the photosynthetic potential of the population by coordinating the reasonable distribution of light energy in the upper three leaves to construct the dominant population of rice under dry cultivation. Photosynthetic potential of 105.55m2·d/m2, light energy interception rate of 31.21% in the inverted second leaf and plant height of 101 cm at 10 days after flowering were important external characteristics of the dominant population of rice under dry cultivation. The ability of the inverted second leaf to intercept light energy is the basis for ensuring the photosynthesis of the population. The simultaneous coordination of photosynthetic enzyme activity, net photosynthetic rate and chlorophyll content in the inverted second leaf is an important physiological characteristic of the photosynthetically dominant group. The variation of photosynthetic physiological indexes in the inverted second leaf was characterized by ‘from genes to enzyme activity to net photosynthetic rate and chlorophyll, and the spatial variation was from the upper leaves to the lower leaves’. ‘ Protect the flag, promote the second, stabilize the third ’ (Maintaining photosynthetic capacity of the flag leaf , promoting photosynthetic enzyme activity in the inverted second leaf, and stabilizing photosynthetic gene expression in the inverted third leaf ) is an important tool to construct the dominant population of rice under dry cultivation. These studies have significant implications for the future construction of dominant rice under dry cultivation in different regions and provide an important basis for the study of the regulatory mechanisms of photosynthetic pathways in different leaf positions.

The gas hydrate is attracting increasing attention in the sedimentary geology as an alternative energy source in the future. Recent exploration efforts have indicated that gas hydrate is commonly associated with sediment waves in slope area of quasi-passive continental margin. Based on the deep-water seismic data and core data of the northeastern part of the South China Sea (SCS), this research describes the seismic and geological characteristics of the sediment waves and gas hydrate reservoirs, and discusses the accumulation model of gas hydrate in sediment waves reservoir. The results demonstrate that: (1) the sediment waves widely appear in study area, and those have a “wave-like” bedform and are formed by deep-water contour or turbid current sedimentation. Meanwhile, the sediment waves are affected by gas leakage, diapirism, and neotectonics. (2) The stable zone of gas hydrate which simulated calculation by theory is consistent with core data. The complete and typical gas hydrate seismic model including a “bottom-simulating reflection (BSR) + blank zone (BZ) + enhanced reflector body (eHB)” structure can be observed in the sediment waves seismic profile of the study area. (3) The gas hydrates are stored in sediment waves, which are influenced by the original structure of the sediments and have different gas hydrate accumulation dynamics that are driven by diffusion and/or leakage. Thus, the sediment waves as a favorable reservoir of gas hydrate have research significance.

Shale oil is attracting increasing attention in the petroleum industry as an essential target of unconventional oil and gas exploration. Recent exploration efforts have indicated that laminar carbonates are closely related to the favorable depositional strata of shale oil. This research focused on inter-bedded layers of laminar carbonates as well as mudstone and shale in the Dongying depression of the Bohai Bay Basin in eastern China, and attempted to reveal the genesis and evolution of the carbonates by means of drill core observations, thin sections, high resolution scanning electron microscopic observations, and fluorometric, cathodoluminescence and geochemical analyses. The results demonstrated that: (1) the carbonates could be categorized into two groups, crystalline carbonates and micritic carbonates; (2) the crystalline carbonates were well crystallized and greenish under fluorescent light; and (3) the micritic carbonates were not well crystallized and had biotic textures. It was discovered that the crystalline carbonates were mainly developed in the shale layer and were formed from the late-filling effects of the diagenetic cracks along the shale fissility planes; shale layers with crystalline carbonates are usually favorable for shale oil reserves. The micritic carbonates were formed from direct deposition controlled by biological effects in the stratified flows of the seasonal lake basins and are unfavorable for shale oil reserves.

The negative effects of salt stress vary among different rapeseed cultivars. In this study, we investigated the sodium chloride tolerance among 10 rapeseed cultivars based on membership function values (MFV) and Euclidean cluster analyses by exposing seedlings to 0, 100, or 200 mM NaCl. The NaCl toxicity significantly reduced growth, biomass, endogenous K+ levels, relative water content and increased electrolyte leakage, soluble sugar levels, proline levels, and antioxidant enzyme activities. SPAD values were highly variable among rapeseed cultivars. We identified three divergent (tolerant, moderately tolerant, and sensitive) groups. We found that Hua6919 and Yunyoushuang2 were the most salt-tolerant cultivars and that Zhongshuang11 and Yangyou9 were the most salt-sensitive cultivars. The rapeseed cultivars were further subjected to photosynthetic gas exchange and anatomical trait analyses. Among the photosynthetic gas exchange and anatomical traits, the stomatal aperture was the most highly correlated with salinity tolerance in rapeseed cultivars and thus, is important for future studies that aim to improve salinity tolerance in rapeseed. Thus, we identified and characterized two salt-tolerant cultivars that will be useful for breeding programs that aim to develop salt-tolerant rapeseed.

Diagenesis significantly influences sandstone reservoir quality, so that a detailed understanding of diagenesis is essential for the identification and prediction of favorable reservoirs. Several studies have been conducted on individual sandstone reservoirs in the Bonan Sag, a typical half-graben, oil-producing sag in eastern China, but few have explicitly considered the potential impact of the asymmetric shape of the sag, which is steep in the north and gentle in the south. This research takes full consideration of the tectonic setting and distribution of source rocks in the sag to compare the style, magnitude and timing of diagenesis in the northern Steep Slope and Sag Zone (SSSZ) and the southern Gentle Slope Zone (GSZ) by means of drill core observations, thin section petrography, high resolution scanning electron microscopy, fluid inclusion microthermometry, as well as cathodoluminescence and carbonate stable isotope analysis. Petrographic observations identify the wide-spread occurrence of authigenic quartz and clay minerals in association with dissolved feldspar, as well as abundant carbonate cements occurring as several distinct generations due to evolving pore fluid composition. The SSSZ has variable carbonate mineralogy while ankerite dominates in the GSZ. The homogenization temperature of fluid inclusions in authigenic quartz in the SSSZ has a wider range (93°C–157.9 °C) and lower starting temperature (93 °C) compared with the GSZ (106.2 °C) and is characterized by more lighter carbonate δ13C and δ18O values (δ18O: −14.8‰~-11.3‰, δ13C: 1.1‰–2.7‰ for the SSSZ; δ18O: −11.9‰~-5.8‰, δ13C: 2.9‰–5.5‰ for the GSZ). The results indicate that (1) Diagenetic conditions in the Bonan Sag evolved from alkaline to acidic to alkaline in general, but with distinct late stage carbonate cementation in SSSZ vs GSZ; (2) the diagenetic processes as well as the nature of pore waters varied across different zones and also temporally. Acidic conditions in the SSSZ started earlier and persisted for longer than in the GSZ. (3) The regional differentiation of the diagenetic processes and pore fluid evolution result from the source rock distribution and burial histories which differ across the Bonan Sag because of the asymmetric shape of the half-graben. We propose a model of fluid evolution over space and time which may provide a new framework for understanding the diagenetic processes and the fluid evolution of oil-producing sags and also contribute to the prediction of favorable reservoirs.

The present research study was aimed to identifies the effect of the lithofacies (assemblages) on lacustrine shale oil accumulation, the shale oil layers of the Eocene Shahejie Formation in the Bohai Bay Basin, China, were characterized. The petrological analysis, included core, thin section and scanning electron microscopy observations and X-ray diffraction, indicated that the shale oil layers of the Shahejie Formation are dominated by carbonates, which are characterized by uniform or laminar distributions. The laminar carbonate components were formed through sedimentogenesis or diagenesis. Based on the genesis patterns and the petrology, five major lithofacies (assemblages) were identified in the formation: LF (lithofacies) 1 + 5 is characterized by thin lenticular laminae of crystalline carbonates with black shale; LF2+3 depicts laminae of micritic carbonates with massive lime mudstone; LF3 is a thick layer of massive lime mudstone; LF4 is massive claystone; and LF5 is black shale. The relationship between the lithofacies and the favorability for hosting shale oil reservoirs was investigated using microdrill sampling of the total organic content, reservoir quality analysis, and shale oil-bearing property. In LF1+5, the crystalline carbonates contain abundant interparticle pores, which can act as reservoir spaces, whereas the shale layers have a high potential for hydrocarbon generation. In addition, the hydrocarbon reserves can enter the crystalline carbonates of the assemblage after migrating a short distance. Consequently, LF1+5 is the most favorable assemblage for shale oil accumulation. In addition, LF4 and LF5 have high hydrocarbon generation potentials, and thus a relatively smaller amount of hydrocarbons could accumulate in these assemblages through clay mineral adsorption. Thus, LF4 and LF5 are also valuable sites for shale oil accumulation.

The low-fired high performance piezoelectric ceramics used for multilayer piezoelectric transformer were investigated. Based on the transient liquid phase sintering mechanism, by doping suitable eutectic additives and optimizing processing, the sintering temperature of the quaternary system piezoelectric ceramics with high piezoelectric properties could be lower to about 960–1000°C. The low-temperature sintering multilayer piezoelectric transformer (MPT) has been developed. Some characteristics of MPT were systemically studied. The measurements include the frequency response of input impedance, frequency response of phase difference between input voltage and current, frequency shifting with load, input impedance changing with load, phase difference between input voltage and current shifting with load, and phase difference between input voltage and vibration velocity. The vibration modes and resonance characters of MPT were measured by a Laser Doppler Scanning Vibrometer. Several kinds of MPT with high voltage step-up ratio, high power density, high transfer efficiency and low cost have been industrially produced and commercialized. It reveals a broad application prospect for back-light power of liquid crystal display and piezo-ionizer etc.