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Satellite data assimilation pre-processing plays a crucial role in bridging satellite data pre-processing and numerical weather prediction model assimilation. It involves integrating pre-processed satellite measurements, orbital splicing and sparsification of satellite data, the fusion of boundary condition parameters under satellite pixels, and the assimilation pre-processing quality control of satellite data by using a unified file format and in accordance with the requirements of the data assimilation system. In the variational assimilation of numerical forecasts, assimilation pre-processing filters effective information from satellite pre-processed measurements, supports the positive contribution of satellite data assimilation to numerical forecast operations, and is an important link in determining the efficiency, quality and effectiveness of assimilation of large quantities of satellite data. In response to the complex format of satellite data from multiple channels, CMA has developed a standard format of high time-sensitive satellite data splicing technology in the pre-processing of satellite data assimilation, which effectively reduces the negative impact of the time lag of whole-orbit satellite data on operational numerical prediction. In the assimilation pre-processing of Fengyun satellite data, the assimilation prequality control of multi-spectral data fusion is achieved by front-loading cloud and precipitation detection, data analysis, analysis and other processing into the assimilation pre-processing, which ensures the positive assimilation contribution of Fengyun microwave temperature sounding data and infrared hyperspectral data. In the development of satellite data assimilation pre-processing technology, reprocessing of pre-processed satellite data by using a unified data format, expanding the processing for satellite imagery and active detection data, and front-loading a part of satellite data assimilation quality control function into data assimilation pre-processing are important trends in the development of future assimilation pre-processing technology for Fengyun satellite data.

Zinc-doped CuAl2O4 (Zn-CuAl2O4) nanofiber membranes with a high specific surface area, multi-pore structure, and a partial inverse spinel structure were successfully fabricated by controlling the electrospinning process and calcination atmospheres. The excessive doping of Zn2+ ions results in the formation of ZnAl2O4/CuAl2O4 fiber membrane, which has a poor UV-Vis absorption ability. The diameter of Zn-CuAl2O4 nanofibers is about 80 nm, and the specific surface area of the Zn-CuAl2O4 nanofiber membrane is 45.2 m2/g. XRD and XPS results indicate that Zn-CuAl2O4 nanofiber membranes contain spinel and inverse spinel phases. Compared with pure spinel CuAl2O4 nanofiber membranes, the UV-Vis absorption ability of the Zn-CuAl2O4 nanofiber membrane is enhanced, and transient photocurrent intensity was increased from 0.14 mA/cm2 to 0.16 mA/cm2. The free radical capture experiments and EPR spectra indicate that huge ·O2− are generated on the surface of the Zn-CuAl2O4 nanofiber membrane, and the photocatalytic degradation efficiency of MB is increased by 14%. The Zn-CuAl2O4 nanofiber membranes exhibit excellent cycling stability and have great potential for photocatalytic degradation of dye wastewater. [ABSTRACT FROM AUTHOR]

Researching and developing a new type of diaphragm wall foundation can solve the probl em that the traditional diaphragm wall structure may not meet the high standards of safety and stability of underground structures in some specific engineering environments. This paper focuses on the horizontal bearing characteristic of a new form of foundation, a strip-walled underground diaphragm wall, through a series of model tests. In the tests, nine plexiglass models with different section sizes, wall spacings and wall heights, as well as loading strategies (horizontal loads along and against the wall in the model), were conducted. The influence of the above factors on the horizontal bearing performance of the foundation and the soil resistance distribution around the wall was studied. The results show that when the horizontal load applied along the wall is greater than 50 N, the growth rate of total displacement at the top of the wall gradually decreases; when a horizontal load is applied against the wall, with a uniform change in wall height, the optimal wall spacing is 11 cm. When the same displacement occurs, the bearing performance of the model under the former loading strategy is generally 10% higher than that under the later loading strategy. In addition, the depth where the maximum bending moment along the wall occurred gradually moves downward with the increase in horizontal load, and the increase in wall spacing and wall height has a positive effect on the horizontal bearing characteristic. With the application of load, the maximum bending moment of the wall will gradually decrease along the depth. The increase in wall spacing and wall height can improve the overall flexural stiffness and horizontal bearing performance of the foundation. Lastly, the group wall effect coefficient, β, is put forward, and a simplified formula for calculating the horizontal bearing capacity of a strip wall foundation is proposed. In the formula, β is negatively correlated with the buried depth of the wall and positively correlated with the distance between the walls, and its coefficient is greater than 1. [ABSTRACT FROM AUTHOR]

Due to viscoelastic characteristics, the strength values of the high-modulus asphalt mixtures (HMAM) obtained under different conditions (temperatures, loading rates, and stress states) are quite different, and the serving conditions of asphalt pavements are also varied. Thus, the strength under fixed conditions cannot reflect the mechanical performances of materials under real serving conditions, which leads to inaccuracies in the asphalt pavement structural design. To develop a precise strength evaluating method for high-modulus asphalt mixtures, the strength tests of high-modulus asphalt mixtures were implemented under different conditions (temperatures, loading rates, and stress states) in this study. The test results indicated that for each stress state, the variation of strength with loading rates under different temperatures can be characterized by power functions, and the variation of strength with temperatures under different loading rates can be characterized by exponential functions. The uniform characterizing model of strength under different conditions was established through the dimensionless method and the sigmoidal function. With the effects of temperature, loading rates, and stress states included, the strength obtained can better reflect the mechanical performances in actual pavement serving conditions. The research results contribute to the improvement of the structural resistance design of the asphalt pavement with high-modulus asphalt mixtures. [ABSTRACT FROM AUTHOR]

C6H5BrFNO3, orthorhombic, P212121 (no. 19), a = 3.9894(4) Å, b = 13.6128(11) Å, c = 14.7495(12) Å, V = 801.00(12) Å3, Z = 4, Rgt(F) = 0.0213, wRref(F2) = 0.0465, T = 150(2) K.

In order to realize the high value-added reuse of coal fly ash, a reusable Fe-modified fly ash catalyst was synthesized for ozone catalysis degradation of chemical oxygen demand (COD) in wastewater. Through enhancement of the pretreatment procedure and FeOx modification, the resulting fly ash with Fe modification demonstrated increased specific surface area and porosity. The presence of Fe loading significantly enhances the reactivity of surface oxidizing reactive species, particularly oxygen vacancy, leading to improved adsorption and activation properties towards ozone molecules. Sodium acetate is chosen as a probe for contaminants due to its status as a small organic substance that remains resistant to further direct oxidation by ozone. This makes it suitable for evaluating the catalyst's effectiveness in degrading chemical oxygen demand (COD). The quantitative detection of free radicals revealed the generation of •O2− was nearly 10 times that of •OH and dominated the reaction. This study showcases the potential of fly ash, an industrial byproduct, to be utilized as a cost-effective and easily prepared catalyst with consistent physical and chemical characteristics. [ABSTRACT FROM AUTHOR]

To improve the accessibility of polyimide aerogels (PAs) in diverse application scenarios, the major objective is to create PAs in dimension/geometry on demand. However, their ability to deliver excellent performance and expanded applications remains challenging. Herein, the three-dimensional (3D) printing of Pas, which simultaneously addresses the above concerns, is proposed using a combination of a one-step chemical-imidization sol–gel strategy and direct ink writing. The resultant 3D-printed PAs exhibit many desirable properties, such as high specific surface area (561.7 m2 g−1), low density (66.1 ± 1.4 kg m−3), low thermal conductivity (39.89 ± 0.16 mW m−1 K−1), low shrinkage (<7%), exceptional thermal stability (up to 450 °C) and good mechanical properties. They also possess excellent heat/cold preservation, heat/cold/moisture insulation, air/light permeability, and ammonia/moisture adsorption. All of these are highly desirable for addressing severe environmental concerns. Moreover, the application scalability of 3D-printed PAs is confirmed by the successful incorporation of carbon nanotubes, and the subsequent expanded functionality and application potential. The flexibility of inks/materials and the manipulability of the structures and functions, demonstrates great prospect for synergy management of thermal insulation, gas permeability and light absorption, thus expanding the application of PAs. [ABSTRACT FROM AUTHOR]

Supported ozone catalysts usually take alumina, activated carbon, mesoporous molecular sieve, graphene, etc. as the carrier for loading metal oxide via the impregnation method, sol–gel method and precipitation method. In this work, a Mn-modified fly ash catalyst was synthesized to reduce the consumption and high unit price of traditional catalyst carriers like alumina. As a solid waste discharged from coal-fired power plants fueled by coal, fly ash also has porous spherical fine particles with constant surface area and activity, abd is expected to be applied as the main component in the synthesis of ozone catalyst. After the pretreatment process and modification with MnOx, the obtained Mn-modified fly ash exhibited stronger specific surface area and porosity combined with considerable ozone catalytic performance. We used sodium acetate as the contaminant probe, which is difficult to directly decompose with ozone as the end product of ozone oxidation, to evaluate the performance of this Mn-modified fly. It was found that ozone molecules can be transformed to generate ·OH, ·O2− and 1O2 for the further oxidation of sodium acetate. The oxygen vacancy produced via Mn modification plays a crucial role in the adsorption and excitation of ozone. This work demonstrates that fly ash, as an industrial waste, can be synthesized as a potential industrial catalyst with stable physical and chemical properties, a simple preparation method and low costs. [ABSTRACT FROM AUTHOR]

Rechargeable aqueous Zn‐MnO2 batteries are potential candidates for electrochemical energy storage systems due to their easy fabrication, nontoxicity, and low‐cost features. However, the practical application of the MnO2‐based cathode is impeded by its low electrical conductivity and poor stability during cycling. Herein, the Ti3C2/MnO2 composite cathode is elaborately designed and fabricated via a simple mechanical grinding method. Benefiting from the high conductivity of Ti3C2 MXene along with the abundant active sites of nano‐MnO2, the obtained Ti3C2/MnO2 electrode shows fast ion transfer and enhanced structural stability. Therefore, Ti3C2/MnO2 composite as the cathode of zinc ion battery exhibits superior charge storage performance (354 mAh g−1 at 0.2 A g−1, which is 30% higher than that of pure MnO2 cathode), high cycling stability (85% capacitance retention along with about 100% columbic efficiency after 850 cycles at l A g−1), excellent energy density (467.33 Wh kg−l at 260 W kg−1), and impressive long‐term lifespan (65.1 mAh g−1 over 900 h at 0.1 A g−1). Furthermore, the mechanism related is elucidated via comprehensive characterizations. Herein, it provides a convenient and efficient method to fabricate high‐performance Mn‐based cathode for Zinc‐ion batteries. [ABSTRACT FROM AUTHOR]

Livestock and poultry breeding modes, feed compositions and manure collection systems have regional characteristics, which can directly affect the composition of livestock and poultry breeding manure, energy production by anaerobic digestion and resource utilization of products. The chemical, heavy metal contents and microbiological characteristics of pig manures and digestates were characterized in five pig farms and biogas plants in Quzhou (Zhejiang Province) in this study. The results showed that hemicellulose and cellulose of pig manures could be partly degraded in anaerobic digestion, but lignin was difficultly degraded and accumulated in digestates. The content of Zn was highest in the pig manure and digestate samples, followed by Cu, Cr, As, Ni, Pb, Cd, T1 and Hg. The As content was 16.09–31.22 mg kg−1 in the pig manure and digestate samples, which exceeded the standard limitation requirements in fertilizers in China (≤15 mg kg−1). Bacteroidota, Firmicutes, Proteobacteria and Spirochaetota dominated in the pig manure and digestate samples, with a relative abundance of 73.6%−99.4%. The microbial community structure in the pig manure samples was quite different among the five farms. The pH, contents of lignin, T1 and As had a significant effect on the microbial community structure in the pig manure samples, while the contents of total phosphorus, NO3−–N, cellulose and Pb could significantly influence the microbial community structure in the digestate samples. These findings can provide a theoretical basis for recycling manure and improving biogas engineering in large-scale pig farms. [ABSTRACT FROM AUTHOR]

We describe a woman with flank pain and hydronephrosis. Computed tomography (CT) urography and maximum intensity projection (MIP) reformatted images clearly showed that a long finger-like intraluminal filling defects mass in the left middle ureter. The pathologic biopsy by ureteroscopy revealed that the lesion mainly consists of benign fibrinoid necrosis. A large soft smooth, spindle-like, dark brown mass (approximately 13.5 cm in length) was identified in left middle ureter when open surgery was performed. The segment of the ureter part attached to the stalk of the polyp was excised, then a dismembered ureteroplasty was performed. Pathologic examination revealed that the total polyp was an ischemic infarction, characteristic of cellular swelling, tissue degeneration, fibrinoid necrosis, and thrombosis in its vessels. The surface of the polyp was hardly covered with urothelium, but fibroepithelial polyp was still diagnosed. There was no recurrence during the 3 years of follow-up.

Introducing magnetic property into aerogels will greatly expand their application opportunities. Herein, instead of triethylamine solution, a low-cost and little-toxicity aqueous ammonia is used as the basic solution of polyamide acid (PAA), and tert-butanol is used as the regulator to regulate the pore size of aerogel. Finally, an intelligent polyimide/Fe3O4 (PI/Fe3O4) aerogel is proposed via a unique combination of in-situ deposition and freeze–drying–thermal imidization. As-obtained PI/Fe3O4 aerogel has a low density (0.041 − 0.087 g cm− 3, depending on the doping amount of Fe3O4 nanoparticles), a high thermal decomposition temperature (up to 550 °C, N2 atmosphere), good mechanical properties (even under a compression ratio of 60%), certain recovery performance, and good bending flexibility. Additionally, the PI/Fe3O4 aerogel also shows a saturation magnetization of 84.76 emu g− 3, enabling it to generate magneto-induced shape memory under the action of small magnetic sheets. This work provides a new idea for the preparation of magnetic polyimide aerogel, and may inspire many application opportunities for polyimide aerogel, such as self-sensing flexible actuators, micro-nano switches, and micro-sensing. [ABSTRACT FROM AUTHOR]

Sintered silver (Ag) die-attach has attracted much attention in power systems with high power density and high operating temperature. In this paper, we proposed a novel surface modification method for Ag nanoparticles with organic amines as a coating agent for enhancing the pressureless sintering performance. This work systematically introduced the Ag nanoparticle modification process, Ag paste preparation, and sintering process and compared the changes in the sintering performance of Ag nanoparticles after modification with four different alkyl chain lengths of amines. The study showed that the sintered films of Ag nanoparticle pastes modified with n-octylamine (NOA) can achieve the lowest resistivity of the sintered film and the highest shear strength of the bonded joints. The resistivity of the sintered Ag film is affected by the grain size and microscopic morphology, and the strength of the bonded joints is also related to the sintering density and the amount of organic residues. The thermal behavior of the Ag particles coated with different amines is measured by thermal analysis. Finally, the mechanism of NOA-modified Ag nanoparticles to improve the sintering performance is proposed. This study can provide effective data and theoretical support for the further promotion and application of nano-Ag pressureless sintering. [ABSTRACT FROM AUTHOR]