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Tetrastigma hemsleyanum (T. hemsleyanum) is a traditional medicinal plant that is widely used in China. Cultivated T. hemsleyanum usually encounters cold stress, limiting its growth and quality at key developmental stages. APETALA2 (AP2)/ethylene-responsive factor (ERF) transcription factors (TFs) comprise one of the largest gene superfamilies in plants and are widely involved in biotic and abiotic stresses. To reveal the roles of AP2/ERF TFs during T. hemsleyanum development, 70 AP2/ERF TFs were identified in T. hemsleyanum. Among them, 18 and 2 TFs were classified into the AP2 and RAV families, respectively. The other 50 TFs belonged to the ERF family and were further divided into the ERF and (dehydration reaction element binding factor) DREB subfamilies. The ERF subfamily contained 46 TFs, while the DREB subfamily contained 4 TFs. Phylogenetic analysis indicated that AP2/ERF TFs could be classified into five groups, in which 10 conserved motifs were confirmed. Several motifs were group- or subgroup-specific, implying that they were significant for the functions of the AP2/ERF TFs of these clades. In addition, 70 AP2/ERF TFs from the five groups were used for an expression pattern analysis under three low-temperature levels, namely, -4, 0, and 4 °C. The majority of these AP2/ERF TFs exhibited a positive response to cold stress conditions. Specifically, ThERF5, ThERF31, ThERF46, and ThERF55 demonstrated a more sensitive response to cold stress. Moreover, AP2/ERF TFs exhibited specific expression patterns under cold stress. Transient overexpression and RNA interference indicated that ThERF46 has a specific tolerance to cold stress. These new insights provide the basis for further studies on the roles of AP2/ERF TFs in cold stress tolerance in T. hemsleyanum. [ABSTRACT FROM AUTHOR]

With the increase in global energy demand, people pay more and more attention to the development and utilization of unconventional oil and gas. Organic-rich shale is often considered as the source rock of unconventional oil and gas, and its physical properties will change greatly under the action of high temperature. Therefore, it is necessary to analyze and study the physical properties changes and reasons before and after high-temperature heat treatment. Taking the organic-rich shale of Niutitang Formation in Micangshan area of China as the research object, the physical parameters such as chromaticity, glossiness, hardness, capacitance, impedance, P-wave velocity, porosity, mass loss and TG/DSC were tested before and after heat treatment. The reasons for the changes of physical properties were analyzed in combination with the pyrolysis process of shale. The results are as follows: When the temperature is lower than 300 °C, the physical properties change slightly in a certain range, mainly dehydration reaction. In the temperature range of 300–450 °C, except for the decrease in wave velocity and capacitance, the other physical properties increase greatly. The main reaction is thermal decomposition of kerogen. When the temperature is between 450 °C and 600 °C, the hardness and porosity increase greatly, and the other physical properties continue to change slightly. The main reaction is the decomposition of asphalt and some inorganic minerals. By fitting the physical properties, it can be found that the wave velocity has a linear negative correlation with porosity and a linear positive correlation with capacitance. Porosity is positively correlated with mass loss rate and hardness growth rate. After 390 °C, the mass loss rate of shale increases greatly. The endothermic reaction mainly occurs before 530 °C. Due to the thermal decomposition of organic matter and inorganic mineral components in shale samples, the pore structure and mineral composition of the samples are greatly changed, which further leads to the change of physical properties. [ABSTRACT FROM AUTHOR]

Constraining the distribution of water in different regions of the mantle remains one of the significant challenges to comprehend the global deep water cycle. Geomagnetic depth soundings can provide such constraint through the electrical conductivity structure. Hence, this study aims to propose a regularization technique that can estimate previously unavailable C -response. In the method, the objective function comprised an L 1-norm measured data prediction error and a spectral smoothness constraint term. We used the data error of C -response to weight the predicted error. The L-BFGS method was introduced to determine the minimum point of the objective function, and the regularization parameter decreased adaptively during inversion. Thus, the geomagnetic data processed yielded high-quality C -responses in 31 stations in Eastern China. In addition, we obtained 1-D electrical conductivity profiles in the mantle transition zone (MTZ) beneath Eastern China from C -responses using the L-BFGS method. Compared with the global 1-D model, the conductivity–depth profiles revealed that the MTZ beneath Eastern China is more conductive in the east but more resistive in the west. The conversion of these conductivities to water content based on the mineral physics suggested that the MTZ beneath Eastern China is characterized by a high water concentration, approximately 0.2 and 1 wt per cent in the upper and lower MTZ, respectively. Owing to the inclusion of more stations, the water-rich region could be constrained roughly to the east of the North–South Gravity Lineament (NSGL). Further considering seismic images in the same area, this water content distribution pattern suggested that the front of the stagnant Pacific Plate in the lower MTZ might have reached the NSGL. However, the dehydration reactions in the stagnant slab were more active in the eastern part. Perhaps, some of these fluids migrated into the upper MTZ and could be the source of the trapped water found in the xenoliths from the deep upper mantle beneath Eastern China. [ABSTRACT FROM AUTHOR]

• Polyhalite ore started to decompose into anhydrite and langbeinite at 573 K. • The changes of internal models of vibration of SO 4 indicated a phase transformation. • The most probable mechanism function matched D3 Janders diffusion mechanism. • Calcination and hot-leaching could improve the extraction of potassium. In this paper, the thermal decomposition of polyhalite ore from Dayantan Playa in Qaidam Basin of China was investigated by X-ray powder diffractometry (XRD), Raman spectroscopy (Raman), and thermal analysis techniques (TG-DTG). The dehydration reaction of polyhalite ore takes place with the release of water and starts at about 510 K. The results of X-ray diffraction of roasting sample showed that polyhalite ore starts to decompose into anhydrite and langbeinite at 573 K. Raman spectroscopy, in conjunction with X-ray diffraction, was also used to follow the thermal decomposition of polyhalite ore. The changes of internal models of vibration of the SO 4 ions in sulfates indicated the phase transformation polyhalite, langbeinite, and anhydrite. The reaction kinetics of thermal decomposition of polyhalite ore were successfully modeled by a Coats-Redfern equation (ln g (α) T 2 = ln A R β E 1 − 2 R T E − E R T ) and the activation energy is found to be 208 kJ·mol−1. Additionally, the effect of roasting temperature on potassium extraction from polyhalite ore was studied. [ABSTRACT FROM AUTHOR]

[Display omitted] • Most of the large events occurred in high-V or close to the boundary between low-V and high-V zones. • Prominent low-V and high-σ anomalies in the middle and lower crust reflect crustal fluids. • Crustal fluids may originate from hot and wet upwelling flows in the big mantle wedge. • Crustal fluids affected the nucleation and generation of intracontinental large earthquakes. We present detailed 3-D isotropic P and S wave velocity (Vp, Vs) images and Vp azimuthal anisotropy in source areas of 26 large crustal earthquakes (M5.6–7.8) that occurred in North China during 1966 to 2021. Most of the large earthquakes are located in high-velocity (high-V) zones or close to the boundary between low-velocity (low-V) and high-V anomalies. Prominent low-V and high Poisson's ratio (high-σ) anomalies are revealed in the middle and lower crust under almost all the source areas, which may reflect crustal fluids. The low-V and high-σ anomalies may cause local thinning and weakening of the brittle seismogenic layer above them. The crustal fluids may originate from hot and wet upwelling flows in the big mantle wedge (BMW) beneath East Asia due to corner flows in the BMW and deep dehydration reactions of the stagnant Pacific slab in the mantle transition zone. [ABSTRACT FROM AUTHOR]

With increasing use of chemical oil displacement agents in tertiary recovery and the application of various demulsifiers for crude oil dehydration, a large amount of aging crude oil containing a high ratio of water is produced, and it is very difficult for processing and utilisation. In this article, we chose aging crude oil samples from a union station in an oilfield in China. Sample composition was analysed to demonstrate that the key of aging crude oil dehydration is the removal of solid impurities. Thus, an efficient method of combining heating and chemical treatments was developed to treat aging crude oil. It includes two steps: The first step is washing of aging crude oil with hot water with sodium dodecylbenzene sulfonate; the second step is chemical demulsification of the above mixture with hydrochloric acid and sodium chloride solution. The result showed that 2.9% of solid impurities and 29.2% of water were removed in the first step; 27.2% of oil, 24.3% of water, and 3.47% of solid impurities in the aging crude oil were recycled in the second step. A total 87.07% of aging crude oil could be solved with this method. The present two-step treatment method can ensure that the dehydration process runs normally and efficiently in the union station, making it a promising method in the recycling of aging crude oil. [ABSTRACT FROM AUTHOR]

Intra-continental volcanoes have different origins compared to arc volcanoes, and several conflicting geodynamic mechanisms of intra-continental magmatism have been proposed, which require quantitative testing. In this paper, we investigate numerically possible influences of deep subducted slab dehydration processes for the development of intra-continental volcanoes distributed in northeastern China. We employ 2D thermo-mechanical numerical models to investigate the complex dynamics of long-term subduction process, including slab interaction with mantle transition zone, deep oceanic plate dehydration, trench rollback, and back-arc extension. Our experiments show systematically that water can be transported to the transition zone by stagnant slabs hydrating the overlaying deep asthenospheric mantle. Positively buoyant partially molten hydrous plumes arising from the hydrated area formed atop the slabs can propagate upwards and form partially molten mantle regions under the far field continental plate. Our numerical models thus suggest that the development of widely distributed intra-continental volcanism in northeastern China could be related to the rising of multiple relatively small hydrous plumes triggered by stagnant paleo-Pacific slab dehydration in the transition zone. [ABSTRACT FROM AUTHOR]

More and more saffron has been cultivated in China because of the increasing saffron demand, but no paper has studied the influence of drying methods on the quality of Chinese saffron. In this paper, three different dehydration treatments applied in actual production were evaluated: dehydration with electric oven, vacuum oven, and microwave. We determined that the highest quality of saffron will be obtained when fresh saffron is treated at higher temperatures (no more than 70°C) for a long time by electric oven drying and vacuum oven drying. In microwave drying, treatments at lower microwave power and longer time benefit the quality of saffron. In addition, the influence of the drying method on antioxidants in saffron is discussed. The correlation between individual saffron profiles and the antioxidant value was estimated by spectrum-effect relationships analysis. [ABSTRACT FROM AUTHOR]

• Characterizing mineralogy, geochemistry and microstructure of black shale. • Dissolution, oxidation, dehydration, and neutralization occurred in the slip zone. • The bedding direction determined the hydrochemical differentiation in slip zone. • Sulfuric acid from black shale oxidation led to rock mass deterioration. This work investigated the chemical water–rock interaction of black shale interbedded with limestone along a bedding slip zone and how its deterioration affects the surrounding rock mass in the Xujiaping (XJP) landslide. Many dissolved pits were found on the limestone, and geochemical phenomena were investigated. Rock and water samples from the site were analysed for mineralogy, chemical composition and hydrochemistry. In slip zones, water–rock chemical processes occur in the bedding fractures of interface between black shale and limestone. Thus, a bedding water–rock cyclic reaction experiment was designed with limestone, black shale and black shale interbedded with limestone. Many major elements and heavy elements (Fe, Mn, Si, Zn, Ni, Al, S, Mg, Ca, Na, K, Co and Sr) dissolved out, demonstrating that strong dissolution occurred because of the acidic water during the black shale water–rock interaction. The limestone neutralized the acidic water through black shale oxidation in the interfacial fractures between black shale and limestone, causing deterioration of the slip zone. The acidic water from the fissure network inside the black shale strata migrated along the bedding to the exposed surfaces of cliffs and rock fractures, then evaporated to form secondary mineral phases, including melanterite, rozenite, szomolnokite, and gypsum. The water–rock chemical interaction in the XJP landslide included dissolution, oxidation, dehydration, and neutralization reactions. The accumulation trends and hydrochemical properties at different reaction stages of ions dissolved from the surrounding rock mass in the bedding direction were revealed. The deterioration mechanism was expanded: (i) rock-forming and carbonate minerals were especially prone to dissolution by sulfuric acid from black shale oxidation in the slip zone, and (ii) volume expansion due to the crystallization force of precipitated minerals caused further fracture expansion and deformation. Therefore, geochemical analyses can effectively elucidate the long-term development and nature of slip zones in landslide investigations. [ABSTRACT FROM AUTHOR]

Mechanism of fluids in modifying mineralogy and geochemistry of the fault zone and the role of rock-fluid interaction in the faulting weakening is still debatable. Through analyzing mineralogical compositions, major elements as well as micro-structural characteristics of outcrop samples including wall rocks, low damage zone, high damage zone and oriented fault gouge samples from principal slip zone gouges, mineralogical and geochemical variations of the fault-rocks is observed from Shaba outcrop of Beichuan-Yingxiu surface rupture zone of the Mw 7.9 Wenchuan earthquake, China. The element enrichment/depletion pattern of fault rock shows excellent consistency with the variation pattern of minerals in terms of the notable feldspar alteration and decomposition, decarbonization, coseismic illitization, and chloritization that occurs in the fault zone. The Isocon analysis indicates that the overall mass loss amount of the Shaba fault zone is ranked as low damage zone < high damage zone < fault gouge, while the mass removal within the fault gouge causes the greatest loss amount in the centeral strong-deformation region. The mechanism of material loss and transformation in the fault zone, analyzed by comprehensive study, is found to be complicated: (1) during the coseismic period, the mechanical fracturing, the dehydration reaction and thermal pressurization are likely the main factors; (2) during the postseismic period, infiltration by the postseismic hydrothermal fluids is the key factor. Therefore, the coseismic mechanical fracturing, chemical reaction related to coseismic frictional heating, and postseismic fuild-rock interaction are important factors to change and control the material composition and the fault zone evolution. [ABSTRACT FROM AUTHOR]