Late Mesozoic extension in NE Asia resulted in the development of a large extensional province. Metamorphic core complexes (MCCs) are the major features in this province and have 40Ar/39Ar ages of ...130–110 Ma for the mylonites and U‐Pb zircon ages of 150–110 Ma for the integral granitic intrusions. Based on this and previous studies, this paper summarizes major characteristics of these MCCs and recognizes a regional kinematic shear sense. Most MCCs in the Transbaikalia region, Sino‐Mongolia border tract, and the northwest‐central portion of the North China craton (NCC) show a top‐to‐the‐southeast (SE) shear, whereas those in the eastern and southern NCC locally underwent top‐to‐the‐northwest (NW) shear. The three largest basins (Songliao, Huabei and Ordos) in North China are located in the transitional zone between domains of opposing shear sense. We interpret the extension in the Transbaikalia, Sino‐Mongolia tract and northwestern part of the NCC to reflect late‐orogenic collapse of thickened crust following Middle‐Late Jurassic collision along the Okhotsk suture. The southeastward extension is probably controlled by crustal‐scale top‐to‐the‐SE tangential shear. The transition from contraction to extension is marked by detachment faults that nucleated as extensional crenulation cleavage (ecc, i.e., C′) in sub‐horizontal ductile shear zones late in orogenic crustal thickening. The combined effect of gravitational loading and thermal‐uplifting is considered to be the origin of the late‐or post‐orogenic collapse. The top‐to‐the‐NW extension in the NE of the NCC might reflect antithetic sub‐extensional zones or Mesozoic back‐arc extension as a far‐field effect of Cretaceous Pacific plate subduction.
Key Points
Characteristics of late Mesozoic metamorphic core complexes (MCCs) in NE Asia
Kinematic pattern with shear‐sense polarity for MCCs and basins
Transition from the contraction to extension is marked by extensional detachment
The trap states at grain boundaries (GBs) within polycrystalline perovskite films deteriorate their optoelectronic properties, making GB engineering particularly important for stable high‐performance ...optoelectronic devices. It is demonstrated that trap states within bulk films can be effectively passivated by semiconducting molecules with Lewis acid or base functional groups. The perovskite crystallization kinetics are studied using in situ synchrotron‐based grazing‐incidence X‐ray scattering to explore the film formation mechanism. A model of the passivation mechanism is proposed to understand how the molecules simultaneously passivate the Pb–I antisite defects and vacancies created by under‐coordinated Pb atoms. In addition, it also explains how the energy offset between the semiconducting molecules and the perovskite influences trap states and intergrain carrier transport. The superior optoelectronic properties are attained by optimizing the molecular passivation treatments. These benefits are translated into significant enhancements of the power conversion efficiencies to 19.3%, as well as improved environmental and thermal stability of solar cells. The passivated devices without encapsulation degrade only by ≈13% after 40 d of exposure in 50% relative humidity at room temperature, and only ≈10% after 24 h at 80 °C in controlled environment.
Introducing semiconducting molecules with Lewis acid or base functional groups into a sol–gel MAPbI3 film promotes uniform decoration of grain boundaries within the bulk film. These molecules holistically passivate under‐coordinated Pb2+ vacancies or Pb–I antisite defects, leading to significant enhancements of the power conversion efficiency as well as improved environmental and thermal stability of solar cells.
Transition metal phosphides (TMPs) have shown promising performance in electrocatalytic water splitting. However, the sluggish kinetic of oxygen evolution reaction (OER) process deteriorates their ...activity toward overall water splitting. To overcome this issue, two-dimensional (2D) ultrathin arrays of metal-doped CoP (MCoP; M = Fe, Ni, and Mg) were successfully prepared by using layered double hydroxides (LDHs) as precursors. The as-obtained 2D ultrathin arrays exhibit an outstanding electrocatalytic activity and long-term durability toward both half-reaction in overall water splitting. As a result, the electrolyzer assembled by FeCoP UNSAs consumes a cell potential as low as 1.60V (at 10mAcm−2). An experimental-theoretical combination study reveals that the electronic structure of Co is modulated via the incorporation of Fe, which benefits the adsorption of water molecule and the dissociation of OH group, accounting for the largely enhanced activity toward overall water splitting.
Two-dimensional (2D) ultrathin arrays of FeCoP were fabricated by using layered double hydroxides (LDHs) as precursor, which exhibited excellent electrocatalytic activity toward overall water splitting. Display omitted
•Ultrathin 2D Fe-doped CoP arrays (FeCoP UNSAs) have been successfully synthesized.•The FeCoP UNSAs displays satisfactory activity toward overall water splitting.•The incorporation of Fe benefits adsorption of water and dissociation of OH group.
Water inrush accidents during coal mining still occur after reinforcement of fissured water bearing strata underlying coal seams through grouting, which seriously troubles field technicians. In order ...to further prevent the water inrush, especially the water inrush after grouting reinforcement, the grouting technique needs to be improved. Experimental design, theoretical analysis, and numerical simulation have been carried out in sequence. On the microscale level, the relationship between strains and water flow rate was analyzed through laboratory experiments; on the macroscale level, the propagation mechanism of grouting cracks resulting from the rock strata deformation during coal production was analyzed with rock beam theory, and then a new model of casing pipes preventing water inrush by controlling deformation of the floor rock strata is proposed. The laboratory test results show that the response of the radial strain and the water flow rate to mining operation is consistent and positively correlated and verify that it is feasible to reduce water inrush disaster by controlling deformation of the rock strata. The deformation governing equation of the casing pipes is deduced theoretically. At last, the numerical calculation was done to prove the effectiveness of controlling the floor rock strata deformation by the casing pipe group, which indicated that the displacement of the monitoring points after grouting is smaller than that before grouting practice. It is practicable to realize grouting technique optimization by the innovative adoption of the grouting casing pipes in the future.
Two-dimensional (2D) organic–inorganic perovskites have recently emerged as one of the most important thin-film solar cell materials owing to their excellent environmental stability. The remaining ...major pitfall is their relatively poor photovoltaic performance in contrast to 3D perovskites. In this work we demonstrate cesium cation (Cs + ) doped 2D (BA) 2 (MA) 3 Pb 4 I 13 perovskite solar cells giving a power conversion efficiency (PCE) as high as 13.7%, the highest among the reported 2D devices, with excellent humidity resistance. The enhanced efficiency from 12.3% (without Cs + ) to 13.7% (with 5% Cs + ) is attributed to perfectly controlled crystal orientation, an increased grain size of the 2D planes, superior surface quality, reduced trap-state density, enhanced charge-carrier mobility and charge-transfer kinetics. Surprisingly, it is found that the Cs + doping yields superior stability for the 2D perovskite solar cells when subjected to a high humidity environment without encapsulation. The device doped using 5% Cs + degrades only ca. 10% after 1400 hours of exposure in 30% relative humidity (RH), and exhibits significantly improved stability under heating and high moisture environments. Our results provide an important step toward air-stable and fully printable low dimensional perovskites as a next-generation renewable energy source.
•Salinity Gradient Energy (SGE) recovery of desalinated seawater using RED method.•Verify the feasibility of recovery the SGE by comparative experiments.•High salinity, temperature and flow rate are ...promoting to improve RED stack performance.
Recovery on salinity gradient energy (SGE) usually existing at the junction of rivers and sea, have attracted a large amount of researchers. However, recovery and utilization of the SGE between desalinated seawater and seawater discharged from desalination plants, is relatively unexplored. In this work, a reverse electrodialysis (RED) approach is introduced to recover the SGE and convert it into electric energy. The objectives of this work are: i) exploring the feasibility to recover the SGE by adopting the RED method; ii) investigating the influence of different inlet parameter on the performance of a RED stack. On the basis of above aims, comparative experiments are implemented to verify the feasibility. Then the factors affecting the performance of the RED stack are analyzed. Results show that the power density of desalinated seawater (3.0 mol/L)/seawater (0.50 mol/L) is slightly higher than that of seawater/freshwater (0.060 mol/L), and lower than that of desalinated seawater/freshwater. A high concentration, temperature, and flow rate can improve efficiently the performance of the stack. For a RED stack composed of 10 membrane cells with desalinated seawater in the concentration range of 1.5 mol/L–3.0 mol/L, the open–circuit voltage and the maximum power density can reach 0.966 V and 0.372 W/m2 respectively. This study can provide some guidance for the recovery of SGE between desalinated seawater and seawater.
Mg-based materials are one of the most promising hydrogen storage candidates due to their high hydrogen storage capacity, environmental benignity, and high Clarke number characteristics. However, the ...limited thermodynamics and kinetic properties pose major challenges for their engineering applications. Herein, we review the recent progress in improving their thermodynamics and kinetics, with an emphasis on the models and the influence of various parameters in the calculated models. Subsequently, the impact of alloying, composite, and nano-crystallization on both thermodynamics and dynamics are discussed in detail. In particular, the correlation between various modification strategies and the hydrogen capacity, dehydrogenation enthalpy and temperature, hydriding/dehydriding rates are summarized. In addition, the mechanism of hydrogen storage processes of Mg-based materials is discussed from the aspect of classical kinetic theories and microscope hydrogen transferring behavior. This review concludes with an outlook on the remaining challenge issues and prospects.
Studying the characteristics of cavitation bubble microjets and shock waves is of great significance to reveal cavitation erosion mechanisms in hydraulic engineering. In this paper, a high-speed ...dynamic acquisition system and an electric pulse-induced cavitation bubble system are used to study the interaction between cavitation bubbles and different elastic boundaries from the perspective of microjets and shock waves. By analysing the difference in the microjet direction near different elastic materials, the relationship between the dimensionless critical distance of the microjet direction characteristics and the dimensionless elastic modulus of the boundary material is preliminarily established. Via quantitative analysis, the maximum velocity of the microjet near different elastic boundaries increases gradually and tends to stabilize with increasing dimensionless distance. Additionally, the shock wave intensity and propagation characteristics near different elastic boundaries are qualitatively analysed through images. The cavitation impact characteristics of the microjet and shock wave are compared. The elastic deformation characteristics of elastic materials under the penetration of microjets are the main influencing factors of cavitation erosion of elastic materials, while the effect of the shock wave on elastic materials is weak.
•High-speed imaging captures a spark-generated bubble near different elastic boundaries.•The effect of an elastic boundary on the bubble is complex.•The action of microjet penetration are the main factors affecting the cavitation erosion of elastic materials.•The cavitation erosion of shock waves to elastic materials is weak.•An elastic material can resist erosion within a certain distance from a bubble.
Abstract
Background
Previous studies have identified that socioeconomic status (SES) and obesity are associated with hypertension. However, their interaction on hypertension risk has not yet been ...assessed.
Methods
The study used data from 6,069 Tibetan residents in Chengguan District in Lhasa, the Chinese Tibetan autonomous region’s capital, based on a cohort study conducted from May 2018 to September 2019 in five provinces in southwest China. We used logistic regression models to assess the complex relations of SES and obesity with hypertension.
Results
Compared with individuals of high SES, low and moderate SES were positively associated with high risk of hypertension. SES and obesity have significant additive interaction on hypertension (general obesity by BMI: RERI = 1.33, P < 0.001; abdominal obesity by WC: RERI = 0.76, P < 0.001; abdominal obesity by WHtR: RERI = 0.96, P < 0.001). In people from the low and moderate SES segments, obesity was linked to an increased risk of hypertension, but the correlations were stronger in people from the moderate SES category. Compared with people of high SES and non obese, those with moderate SES and obesity had a higher risk of hypertension, and ORs were 4.38 (2.80, 6.84) for general obesity by BMI, 3.38 (2.05, 5.57) for abdominal obesity by WC, and 3.18 (1.57, 6.42) for abdominal obesity by WHtR.
Conclusion
There is an independent and additive interaction effect of obesity and SES on the risk of hypertension. People with obesity, especially those of moderate and low SES, should reduce weight and waist circumference, and pay more attention to blood pressure. Moreover, the government, health administration departments, and society should prioritize improving the socioeconomic status of the Tibetan population and addressing risk factors like obesity.
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