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Constrictive pericarditis can lead to compromised diastolic ventricular filling due to pericardial inflammation and fibrosis. A diagnosis of constrictive pericarditis was established by identifying structural and hemodynamic features through echocardiography. We present a case of constrictive pericarditis, which manifested in the form of gradually worsening dyspnea and lower-extremity edema over a 7 years period. The patient was diagnosed with constrictive pericarditis using echocardiography, and underwent a pericardiectomy. [ABSTRACT FROM AUTHOR]

MXene is a promising energy storage material for miniaturized microbatteries and microsupercapacitors (MSCs). Despite its superior electrochemical performance, only a few studies have reported MXene‐based ultrahigh‐rate (>1000 mV s−1) on‐paper MSCs, mainly due to the reduced electrical conductance of MXene films deposited on paper. Herein, ultrahigh‐rate metal‐free on‐paper MSCs based on heterogeneous MXene/poly(3,4‐ethylenedioxythiophene)‐poly(styrenesulfonate) (PEDOT:PSS)‐stack electrodes are fabricated through the combination of direct ink writing and femtosecond laser scribing. With a footprint area of only 20 mm2, the on‐paper MSCs exhibit excellent high‐rate capacitive behavior with an areal capacitance of 5.7 mF cm−2 and long cycle life (>95% capacitance retention after 10,000 cycles) at a high scan rate of 1000 mV s−1, outperforming most of the present on‐paper MSCs. Furthermore, the heterogeneous MXene/PEDOT:PSS electrodes can interconnect individual MSCs into metal‐free on‐paper MSC arrays, which can also be simultaneously charged/discharged at 1000 mV s−1, showing scalable capacitive performance. The heterogeneous MXene/PEDOT:PSS stacks are a promising electrode structure for on‐paper MSCs to serve as ultrafast miniaturized energy storage components for emerging paper electronics. [ABSTRACT FROM AUTHOR]

To examine the effect mechanism of rubber and diatomite on asphalt as well as the performance of asphalt mixtures for road applications, various composite-modified asphalts are prepared using rubber and diatomite. The performance of modified asphalts with various proportions is analyzed, and the optimal dosage ratio of modifiers is determined via the response surface approach. The microstructure of rubber–diatomite composite-modified asphalt is methodically examined using Fourier transform infrared spectroscopy and scanning electron microscopy. The road performance, aging resistance, and long-term stability of asphalt mixtures are evaluated through Marshall tests, wheel tracking tests, aging wheel tracking tests, freeze–thaw splitting tests, and cyclic freeze–thaw drying aging splitting tests. The obtained results reveal that asphalt with 22% rubber and 4% diatomite exhibits the best overall performance. The composite-modified asphalt essentially demonstrates the physical blending between rubber powder, diatomite, and base asphalt. The asphalt built from them formed a uniform and stable overall structure. Compared with rubber asphalt and rubber–SBS composite-modified asphalt, rubber–diatomite composite-modified asphalt exhibits superior road performance, including better aging resistance and long-term water stability in asphalt mixtures. This study can promote the further extensive application of rubber–diatomite-modified asphalt in road engineering, while providing new ideas for cost-saving and environmentally friendly asphalt modification. [ABSTRACT FROM AUTHOR]

A recyclable biogum thickener was developed and employed as the main agent to compound a fracturing fluid system in order to address the issue of the problematic recovery of fracturing fluid system. By using infrared (IR), nuclear magnetic resonance (NMR), X‐ray diffraction (XRD), and scanning electron microscopy (SEM), the physical characteristics and microstructure were examined. By using a rheometer, dynamic filtration loss, and an acid‐etching fracture conductivity device, respectively, the system's temperature and shear resistance, dynamic filtration loss, and fracture conductivity damage were studied. The system's gum‐breaking performance, formation water compatibility, and anti‐expansion performance were then measured in accordance with standards. As a result of shearing at 170 s−1 and 120°C for 2 h, the 4% biogum system's performance outperformed the other two systems in every way, according to the experimental findings. Its viscosity could also exceed 70 mPa · s. After breaking, the solution had a viscosity of 2.5 mPa · s, which was very compatible with the formation water. The system has a 90% anti‐swelling rate, a filtration loss coefficient of 5.14 × 10−5, strong infiltration ability, and negligible formation damage. The biogum system's recovery rate after field application is discovered to be around 50%. [ABSTRACT FROM AUTHOR]

In this paper, a guar gum‐based hydraulic fracturing fluid suitable for low permeability oil and gas reservoirs was prepared using alkylamine guar gum (J580) as a thickening agent. The viscosification mechanism and comprehensive properties were analyzed to provide theoretical support for improving the fracturing fluid utilization rate and oil and gas field development in Changqing Oilfield. In this experiment, the properties and microstructure of thickener J580 were analyzed by infrared spectroscopy (FT‐IR), nuclear magnetic resonance (1H‐NMR), X‐ray diffraction (XRD), and transmission electron microscope (TEM). The rheometer, dynamic filtration device, and acid erosion fracture conductive ability device were used to study the temperature and shear resistance performance, viscoelastic properties, dynamic filtration performance, and fracture conductive ability damage of the system. the gel breaking performance, formation water compatibility, and anti‐swelling performance of the system were measured according to the standard. The results show that J580 is an amine modified product of guar gum, and its viscosity increasing mechanism is similar to that of guar gum. The breaking time of the system is 375 s, the residue content is 413 mg/L, and the surface tension is 26.49 mN/m. At 90°C, the viscosity of the solution can be maintained at 180 mPa · s, loss modulus G" dominates, the anti‐swelling rate is 82.5%, the damage rate of the conductive ability is 22.40%, and the dynamic filtration coefficient is 1.3 × 10−5 m/s1/2. The fracturing fluid system has good dynamic filtration performance, conductive ability, temperature and shear resistance, good structural strength, can easily break glue and return, and less residue content. [ABSTRACT FROM AUTHOR]

The Guanjingang water plant has a capacity of 300,000 m3/d and is one of the main water plants of Jiaxing City in Zhejiang Province, which is located in the southern suburban area of this city. Its second phase with an augmentation of capacity of 150,000 m3/d was put into operation in September, 2012. The raw water for this plant is the surface water that purified by the artificial wetlands and goes through the combined treatment of a biological preprocess, with both conventional and advanced process, to ensure the water quality meets the standard. This paper mainly focuses on the three key problems: the seasonal high ammonia-nitrogen, biological security and pH control of outlet water. And it aims to optimize and analyze the combined processes including the artificial wetlands, biological pretreatment, sand filtration and advanced treatment with ozone-activated car-bon. Subsequently, the new treatment process applied to this practical engineering design is proposed.

As a promising candidate material replacing Pb(ZrTi)O 3 (PZT), the lead-free Bi 0.5 Na 0.5 TiO 3 (BNT) system exhibits outstanding piezoelectric and ferroelectric properties. However, the weak thermal stability of these electric properties hampers its practical applications. In this work, we designed and prepared novel Nb-doped 0.76Bi 0.5 Na 0.5 TiO 3 -0.24Bi 0.5 K 0.5 TiO 3 (BNT-BKT) ceramics with superior temperature stability of electric properties. Both strain as well as discharging properties of 5% Nb-doped BNT-BKT ceramics varied less than 3% and 12.5% respectively from room temperature to 160 °C, ascribed to the enlarged gap between the depolarized temperature ( T d or T F-R ) and the maximum dielectric temperature ( T m ). In addition, we investigated the impacts of Nb doping on the phase transition, dielectric, piezoelectric and ferroelectric behaviors of BNT-BKT ceramics in detail. Temperature dependent dielectric spectrums indicated that T d decreased below room temperature with Nb modifying, revealing that the phase structure transformed from ferroelectric into ergodic relaxor. Accordingly, the maximum strain value of 0.21% and recoverable energy storage of 1.2 J cm -3 were simultaneously acquired at the critical composition of 5% Nb incorporation. Our results provide an effective means of obtaining BNT-based ceramics with simultaneously thermally stable strain and discharge properties for wide temperature actuator and capacitor applications., Competing Interests: There are no conflicts of interest to declare., (This journal is © The Royal Society of Chemistry.)