Understanding the relationship between pore size, surface charge density, and Cu2+ adsorption in mesoporous silica.

This research delved into the influence of mesoporous silica's surface charge density on the adsorption of Cu2+. The synthesis of mesoporous silica employed the hydrothermal method, with pore size controlled by varying the length of trimethylammonium bromide (CnTAB, n = 12, 14, 16) chains. Gas adsorption techniques and transmission electron microscopy characterized the mesoporous silica structure. Surface charge densities of the mesoporous silica were determined through potentiometric titration, while surface hydroxyl densities were assessed using the thermogravimetric method. Subsequently, batch adsorption experiments were conducted to study the adsorption of Cu2+ in mesoporous silica, and the process was comprehensively analyzed using Atomic absorption spectrometry (AAS), Fourier transform infrared (FTIR), and L3 edge X-ray absorption near edge structure (XANES). The research findings suggest a positive correlation between the pore size of mesoporous silica, its surface charge density, and the adsorption capacity for Cu2+. More specifically, as the pore size increases within the 3-4.1 nm range, the surface charge density and the adsorption capacity for Cu2+ also increase. Our findings provide valuable insights into the relationship between the physicochemical properties of mesoporous silica and the adsorption behavior of Cu2+, offering potential applications in areas such as environmental remediation and catalysis.

Investigation into the Rheological Properties and Microstructure of Silt/Crumb Rubber Compound-Modified Asphalt.

Near the coast of China, a large amount of sediment is produced during construction work. In order to mitigate the environmental damage caused by sediment and enhance the performance of rubber-modified asphalt effectively, solidified silt material and waste rubber were prepared to modify asphalt, and its macroscopic properties, such as viscosity and chemical composition, were determined via a routine physical test, DSR, Fourier Transform Infrared Spectroscopy (FTIR), and Fluorescence Microscopy (FM). The results show that, with the increase in powder particles and the addition of a certain amount of hardened mud, the mixing and compaction temperature of modified asphalt can be significantly increased-still reaching the design standard. In addition, the high thermal stability and fatigue resistance of the modified asphalt were clearly better than those of the ordinary asphalt. From the FTIR analysis, rubber particles and hardened silt only exhibited mechanical agitation with the asphalt. Considering that excessive silt might result in the aggregation of matrix asphalt, the addition of an appropriate amount of hardened solidified silt material can eliminate the aggregation. Therefore, the performance of modified asphalt was optimum when solidified silt was added. Our research can provide an effective theoretical basis and reference values for the practical application of compound-modified asphalt. Therefore, 6%HCS(6:4)-CRMA have better performance. Compared to ordinary rubber-modified asphalt, the composite-modified asphalt binder has better physical properties and a more suitable construction temperature. The composite-modified asphalt uses discarded rubber and silt as raw materials, which can effectively protect the environment. Meanwhile, the modified asphalt has excellent rheological properties and fatigue resistance.

Solar-Radiation-Dependent Anisotropic Thermal Management Device with Net Zero Energy from 4D Printing Shape Memory Polymer-Based Composites.

Reports have pointed out that nearly 50% of the global total energy demand for buildings is used for daily heating and cooling. Therefore, it is very important to develop various high-performance thermal management techniques with low energy consumption. In this work, we present an intelligent shape memory polymers (SMPs)-based device with programmable anisotropic thermal conductivity fabricated by a 4D printing technique to assist in thermal management with net zero energy. Highly thermal conductive BN nanosheets were textured in a poly (lactic acid) (PLA) matrix by 3D printing, and the printed composites lamina exhibited significant anisotropic thermal conductivity. The direction of heat flow in devices could be switched programmably, accompanying the light-activated deformation controlled by grayscale of composite, which was demonstrated by the "windows" arrays composed of in-plate thermal conductivity facets and SMPs-based hinge joints, achieving the programmable movement of opening and closing under different light conditions. Based on solar radiation-dependent SMPs coupled with the adjustment of heat flow along anisotropic thermal conductivity, the 4D printed device has been proved in concept for potential applications in thermal management in a building envelop for dynamic climate adaptation, taking place automatically based on the environment.

The Facile Strategy of Improving the Long-Term Stability of Highly Transparent Polyvinyl Chloride by Introducing Unsaturated Zn Oleate and Uracil Derivatives.

In order to improve the initial color and the long-term heat stability of super-transparent polyvinyl chloride (PVC), a series of composite heat stabilizers consisting of unsaturated Zn oleate and uracil derivatives have been designed in this paper. The uracil derivatives are 1,3-dimethyl-6-amino-uracil (DAU) and 6,6'-diamino-1,1',3,3'-tetramethyl-5,5'-(ethylidene)bisuracil (OSU). The static thermal stability, dynamic thermal stability, and transparency were used to evaluate the properties of the stabilized transparent PVC sheets. The results indicate that the compatibility between the stabilizer and PVC was greatly enhanced by introducing an unsaturated long-chain Zn oleate and a long alkyl chain bisuracil derivative. Through the thermal discoloration test, the best ratio of DAU/zinc oleate (DAU/Zn) and OSU/zinc oleate (OSU/Zn) was determined to be 4:1, with a total amount of 3 phr in 100 phr PVC. It was verified that the combination of zinc oleate with uracil derivatives could improve the long-term thermal stability of PVC, and the DAU/Zn was better than that of the OSU/Zn. In addition, through the transmission/haze verification, adding a proper amount of epoxidized soybean oil (ESBO) and phosphite ester to the OSU/Zn system has a certain synergistic effect. The thermal stability and transparency of PVC can be remarkably enhanced.

[Carbonized Foam Supported Co3O4 Activated Peroxymonosulfate Towards Rhodamine B Degradation].

Co3O4 has received much attention because of its excellent performance in activating peroxymonosulfate. However, the practical application of Co3O4 has been seriously restricted by the problems of agglomeration of Co3O4, difficult separation, easy loss, and poor recycling. In this study, the CMF/Co3O4 heterogeneous catalyst was prepared using the hydrothermal method. The crystal structure and morphology of CMF/Co3O4 were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Rhodamine B (RhB) degradation was employed as a model test for evaluating potassium peroxymonosulfate (PMS) activation. The degradation rate of RhB can reach 98% in the catalyst dosage of 35 mg·L-1, PMS concentration of 50 mg·L-1, pH of 7, and RhB initial concentration of 10 mg·L-1 after a 30 min reaction. The results showed that the degradation rate of RhB could be significantly improved by increasing the amount of CMF/Co3O4 heterogeneous catalyst and the mass concentration of PMS. The degradation rate of RhB can be inhibited by increasing the initial mass concentration of RhB and pH value. The process of degradation of RhB can be fitted by using the pseudo first-order kinetics model. The effect of temperature on the degradation rate of RhB conformed to the Arrhenius model, and the degradation process was a surface reaction-controlled process. The results of the free radical capture experiment showed that the sulfate radicals were the dominant active species for RhB degradation. After four cycles, the degradation rate of RhB still remained above 93% with CMF/Co3O4 catalyst.

Preparation and performance of photocatalytic NO degradation superhydrophobic coatings for tunnel.

Due to the semi-closed structure of the tunnel, serious air pollution in tunnels from vehicle exhaust becomes an issue which needed to be addressed. Among the exhaust, nitric oxide (NO) is typically considered as one of the main pollutants. In this paper, a superhydrophobic photocatalytic coating was fabricated by a spraying method by airbrush with a WO3/TiO2 photocatalysis for NO degradation. The water advanced contact angle (WACA) of the coating reached 166.32°, and the WACA was still above 145° after the 30 times abrasion test. The coating exhibited an excellent ability to remove inorganic and organic pollutants. Also, the NO degradation efficiency of this superhydrophobic coating under ultraviolet and visible light sources and humid environments was tested. When the relative humidity reached 98%, the NO degradation efficiency of the coating remained unchanged under visible light irradiation compared with the relative humidity of 45%. In addition, the coating exhibited prominent stability of NO degradation during the cyclic test. Furthermore, the WT coating showed stability and synergy of self-cleaning and photocatalysis toward NO degradation, which ensured the long-term use of the coating. Finally, a synergistic mechanism for self-cleaning and photocatalysis was proposed. This may provide a new idea and support for the application of photocatalytic technology in the degradation of NO in the tunnel.

Improvement mechanism of NO photocatalytic degradation performance of self-cleaning synergistic photocatalytic coating under high humidity.

Photocatalytic coating has been widely studied as a promising material to remove air pollutants. However, the effectiveness and long-term effect of photocatalysis in high relative humidity environment is still the main challenge in this field. In this study, a fluorinated WO3-TiO2 nanorods/SiO2 epoxy photocatalytic superamphiphobic coating (FTSE coating) was prepared using a simple spraying method. The micromorphology and chemical composition of FTSE coating was characterized by SEM, EDS, FT-IR, XPS and TGA techniques. The advanced contact angle and hysteresis angle test show that the FTSE coating had excellent superamphiphobicity. The mechanical abrasions, corrosion resistance and UV aging tests show that the FTSE coating exhibited reasonable durability. Besides, the NO degradation efficiency of hydrophilic and superamphiphobic coatings with contact angles of 20.19°, 87.74°, 162.93° and 164.47° was tested in different humidity environment. The results showed that the superamphiphobic coating exhibited more superior photocatalytic degradation efficiency (84.02%) than the hydrophilic coating (51.38%) at a high relative humidity (RH=98%). Finally, FTSE coating exhibited prominent photocatalytic stability and the synergistic effect of photocatalysis and self-cleaning. After 30 d outdoor weathering test, the NO degradation efficiency decreased by 13.07% and recovered to the original level after flushing. The improvement mechanism of NO degradation performance was proposed based on the characteristics of superamphiphobic surface.

Diversity of soil nitrogen-fixing bacteria in the rhizosphere and non-rhizophere soils of Ebinur Lake Wetland.

Ebinur Lake Wetland is an understudied desert wetland ecosystem, particularly regarding nitrogen cycling. This study aimed to ascertain the diversity and richness of nitrogen-fixing bacterial communities in the Ebinur Lake Wetland. The diversity of the nitrogen-fixing bacteria community of nifH genes from the rhizosphere and non-rhizosphere soils of four plants in different seasons were examined using Illumina HiSeq PE250 high-throughput sequencing technology. The correlation between soil environmental factors and diversity and richness of nitrogen-fixing bacteria was studied using the redundancy analysis (RDA). The results showed that the diversity of nitrogen-fixing bacteria in the rhizosphere soil of the constructive plants was higher than that in the non-rhizosphere soil; also, the diversity in July was higher than that in October and April. Geobacter, Pseudomonas and Bradyrhizobium were the dominant common bacteria in different samples of Ebinur Lake Wetland. The RDA showed that the total nitrogen, available potassium and available phosphoruswere significantly correlated with the diversity and richness of nitrogen-fixing bacteria. The diversity and community structure of nitrogen-fixing bacteria in soil samples also changed over time. The community structures of nitrogen-fixing bacteria in the rhizosphere and non-rhizosphere soils of the four plants were not the same during the same period. The correlation between soil environmental factors and the community structure and abundance of nitrogen-fixing bacteria can provide data basis and theoretical support for the degradation and restoration of Ebinur Lake Wetland.

Controllable Synthesis of Enhanced Visible Light Responded Fe, N, Co Tri-TiO2@MCM-41 Nanocomposites and Its Photocatalytic Performance.

A novel method for in situ synthesis of Fe, N, Co tri-TiO2 (DT) loading on MCM-41 composite photocatalyst was proposed. Fe, N, Co tri-TiO2@MCM-41 (DTM) with adsorption-degradation synergy was prepared by adjusting tetrabutyl titanate (TBOT) concentrations, the alcohol-water ratio in the atmosphere of the reaction chamber. The influence of preparation parameters on the texture structure, catalytic activity, and the synergism of adsorption and degradation of the DTM was discussed, the optimal parameters were determined. The DTM was characterized by XRD, TEM, BET, FT-IR, and UV-Vis. Besides, the DTM exhibited obvious redshift and visible catalytic activity compared with undoped TiO2@MCM-41 (TM), which possessed excellent performance in the degradation of gaseous and liquid pollutants. The degradation rate of methylene blue (MB) and nitric oxide (NO) was 96.39% and 56.75%, respectively. Furthermore, DTM photocatalyst exhibited excellent reusability. The degradation efficiency of MB and NO after five cycles decreased by 4.54% and 5.89%, respectively.

Photocatalytic Superamphiphobic Coatings and the Effect of Surface Microstructures on Superamphiphobicity.

In recent years, superamphiphobic coatings have been widely used in industrial transportation and environmental treatments because of their unique liquid repellency. In this study, WO3-TiO2 nanorods/SiO2 were used as the constructor of surface microstructures, and 1H,1H,2H,2H-perfluorodecyltriethoxysilane was used as the provider of low surface energy, and a photocatalytic superamphiphobic coating (FTS coating) was prepared. The microstructure and chemical composition of the coating was characterized by scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), Fourier-transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), and thermogravimetric analysis (TGA). The coating exhibited excellent photocatalytic activity toward degradation methyl red and nitric oxide (NO), and the degradation efficiency to NO reached 47.8%. Also, the advanced contact angle and the hysteresis angle of water, glycol, glycerol, and olive oil was used to evaluate the superamphiphobicity. After 7 days of ultraviolet (UV) aging, five cycles of airbrush flushing and 48 h of immersion in acid, salt, and alkali solutions, the FTS coating still exhibits excellent amphiphobicity, which lays a foundation for its large-scale applications in the concrete exterior wall. The surface microstructure and the formation of air pockets are a prerequisite for superamphiphobicity, which promotes the liquid on the coating surface into the Cassie-Baxter state. Furthermore, the formation of air pockets is closely related to the gas adsorption capacity and the specific surface area (SBET) of the surface microstructure on the coating surface. The coatings with different SBET constructed and the advanced contact angle were measured. The influence of air pockets on the superamphiphobicity of coatings was studied in combination with the optical microscope. The understanding that SBET further influences superamphiphobicity by affecting the surface air pockets is proposed.

Diversity and community structure of ammonia-oxidizing archaea in rhizosphere soil of four plant groups in Ebinur Lake wetland.

The aim of this study was to reveal the differences in the community structure of ammonia-oxidizing archaea (AOA) between rhizosphere and non-rhizosphere soil, to provide a theoretical basis for further study on the relationship between halophyte rhizosphere soil microorganisms and salt tolerance. The results of diversity and community structure showed that the diversity of the AOA community in rhizosphere soil of Reeds was higher than that in non-rhizosphere soil in spring and lower than that in non-rhizosphere soil in summer and autumn. In summer, the diversity of rhizosphere soil of Karelinia caspica was higher than that of non-rhizosphere soil and lower than that of non-rhizosphere soil in spring and autumn. The diversity of rhizosphere soil of Halocnemum strobilaceum in 3 seasons was lower than that in non-rhizosphere soil. The diversity of rhizosphere soil of Salicornia was higher than that in non-rhizosphere soil in 3 seasons. In addition, the relative abundance of AOA in rhizosphere soil of 4 plants was higher than that in non-rhizosphere soil. The AOA community in all soil samples was mainly concentrated in Crenarchaeota and Thaumarchaeota. Redundancy analysis results showed salinity, soil water moisture, pH, and soil organic matter were important factors affecting the differentiation of AOA communities.

[Clinical feature analysis of 190 patients with anti-neutrophil cytoplasmic antibodies associated vasculitis].

OBJECTIVE: To explore the clinical features and disease spectrums for ANCA (anti-neutrophil cytoplasmic antibodies)-associated vasculitis (AAV) and to improve its cognition. METHODS: Clinical features of 190 cases of patients with AAV hospitalized from 1998 to 2008 were reviewed retrospectively. According to the result of ANCA test, the patients were divided into two groups, cytoplasmic ANCA (C-ANCA) positive and perinuclear ANCA (P-ANCA) positive. The authors compared the differences of disease spectrums, clinical manifestations and laboratory tests between two groups. The relative mortality factors were also analyzed. RESULTS: The authors studied 92 males and 98 females with an age range of 8 - 89 (59 +/- 18) years old. There were 156 cases aged 40 - 80 years old (82.1%) and 162 patients (85.3%) were of primary AAV including 146 cases of P-ANCA positive and 16 cases of C-ANCA positive. There were 28 patients with secondary AAV including 18 cases of connective tissue disease, 7 cases of propylthiouracil induction, 1 case each of idiopathic thrombocytopenic purpura, lung cancer and endometrial carcinoma. There were 25 cases of P-ANCA positive and 3 cases of C-ANCA positive in secondary AAV. There were 171 cases (90.0%) in P-ANCA group and 19 cases (10.0%) in C-ANCA group. The number of organ involvement was 2.53 in C-ANCA group and 1.92 in P-ANCA group. Gastrointestinal tract, joint, upper respiratory tract and ocular involvement was more in C-ANCA group than in P-ANCA group. Oral and auricular involvement was more in P-ANCA group than in C-ANCA group. The involvement difference was of statistic significance in upper respiratory tract, joint and eye (all P < 0.05). Renal and pulmonary involvement in P-ANCA group was similar to C-ANCA group. There were 3 mortality cases in C-ANCA group and 22 in P-ANCA group. Respiratory failure and multiple organ dysfunctions were relative mortality factors. CONCLUSIONS: AAV is observed in elders with multiple organ involvement. The number of organ involvement in C-ANCA group is more than that in P-ANCA group. P-ANCA positive patients are more than c-ANCA patients. The disease spectrum is different in these two groups. Secondary AAV is more in P-ANCA group than in C-ANCA group. Clinical manifestations, laboratory tests and type of ANCA are helpful for the diagnosis of AAV.

Size-selective catalytic activity of Pd nanoparticles encapsulated within end-group functionalized dendrimers.

The synthesis and size-selective catalytic activity of Pd nanoparticles encapsulated within dendrimers functionalized with different-sized end groups is described. We designed and synthesized a series of fourth-generation poly(amidoamine) dendrimers having various extents of steric crowding on their periphery. This was accomplished by reacting the terminal amine groups of these dendrimers with epoxyalkanes substituted with different-sized alkyl groups. The modified dendrimers were characterized by 1H NMR, 13C NMR, and matrix-assisted laser desorption ionization mass spectrometry. Nearly monodisperse (1.7 +/- 0.2 nm) Pd nanoparticles were encapsulated within the interior of these dendrimers, and the resulting composite catalysts were used for the hydrogenation of three alpha-allylic alcohols having different sizes. The results showed a clear correlation between the extent of steric crowding on the dendrimer surface and the turnover frequencies (TOFs) for the substrates: more steric crowding on the dendrimer surface led to lower TOFs.