Influence Of Different Ratios Research Articles

Association between serum uric acid to serum creatinine ratio with cardiovascular and all-cause mortality in adults with hypertension

The serum uric acid to serum creatinine ratio (SUA/sCr) is a standardized index of renal function. More importance was attached to the significance of this ratio in the progression of hypertension. While the association between the prognosis of hypertension and SUA/sCr is unknown. Therefore, we aimed to prospectively examine the associations of serum uric acid to serum creatinine ratio and all-cause and CVD mortality in adults with hypertension. Participants with hypertension from NHANES 1999–2018 (n = 15,269) were included. They were stratified by 1 increment of SUA/sCr ratio and categorized into 6 groups as ≤ 4, > 4 to 5, > 5 to 6, > 6 to 7, > 7 to 8, and > 8. The reason for categorization in 6 groups was to analyze the influence of different ratios on outcomes accurately and provide more precise guidance. The sample size is large enough that even if divided into 6 groups, it does not affect the statistical power. The primary outcomes were all-cause and CVD mortality. Weighted multivariable Cox proportional hazards regression models were used to estimate hazard ratio (HRs) of mortality. Restricted cubic spline regression models were utilized to examine dose–response associations between the serum uric acid to serum creatinine ratio and all-cause and CVD mortality. Relatively comprehensive stratified analyses were conducted to confirm the accuracy and stability of the results. There were 15,269 total participants, 49.4% of whom were men, with an average age of 56.6 years. Weighted multivariable Cox proportional hazards regression models demonstrated participants in the lowest group (≤ 4) had the HRs (95% CIs) of 1.43 (1.18, 1.73) for all-cause mortality and 2.8 (1.92, 4.10) for CVD mortality when compared to the reference group. Participants in the highest group (> 8) had the HRs (95% CIs) of 0.47 (0.25, 0.89) for CVD mortality when compared to the reference group. There were progressively lower risks for all-cause and CVD mortality with the SUA/sCr ratio increased (both P trend < 0.01). The SUA/sCr ratio was (P for nonlinearity < 0.01) nonlinearly correlated with all-cause mortality, with inflection points of 6.25. In addition, the restricted cubic splines results indicated that the SUA/sCr ratio (P for nonlinearity = 0.32) showed linear and negative associations with cardiovascular mortality with inflection points of 6.54. The inverse associations between SUA/sCr ratio and all-cause mortality were consistent across all subgroups except for the subgroup of eGFR < 45 ml/min/1.73 m2 and never smokers (P trend = 0.20 and 0.13, respectively), and the inverse associations between low SUA/sCr ratio and CVD mortality were consistent across all subgroups (P trend < 0.01). Contrary to previous studies, outcomes suggest that lower SUA/sCr ratio was associated with higher risks of all-cause and CVD mortality in adults with hypertension.

Numerical study on aerodynamic characteristics of Mars parachute system with different combinations of fabric permeability and structural porosity

Supersonic parachute plays a crucial role in Mars exploration missions. However, future's large payload exceeds the maximum allowed one of disk-band-gap parachute, new generations of supersonic disksail and ringsail parachute had failed in their flight tests, which may be related to their complicated permeabilities (fabric permeability and structural permeability). Till now, most effects on fabric permeability are mostly considered in subsonic flows, and the influence mechanism of fabric permeability under supersonic conditions is rarely reported. In this study, different permeability schemes (including fabric and structural permeabilities) are designed for a supersonic disksail parachute system. The influence of different ratio of structural permeability to fabric permeability under same total porosity on the flow fields around a parachute system and aerodynamic performance is compared and analyzed. As a result, when the ratio of structural permeability to fabric permeability is 5:5, the stability of parachute shows better than other air permeability schemes. When the ratio is 7:3, the canopy has the best drag performance. With the contribution of fabric permeability increased from 30% to 70%, the drag performance of parachute presents a decreasing trend. Then, the porosity schemes with better aerodynamic performance are placed under Martian atmosphere conditions. The results show that in supersonic flows, when the ratio is 7:3, the aerodynamic performance of parachute is better. In transonic stage, the parachute with ratio of 7:3 has better drag performance, while the parachute with ratio of 5:5 has better stability. In subsonic stage, the parachute with ratio of 5:5 has better drag and stability performance.

Effect of combined application of organic and chemical fertilizers on yield and quality of Epimedium pubescens

To investigate the effects of different ratios of organic and chemical fertilizers on the yield and quality of Epimedium pubescens,so as to provide a scientific basis for the fertilization of high-yield and high-quality E. pubescens cultivation. In this experiment,a field plot test was conducted,and CK(without fertilizer) was set as the control group,with five treatment groups with different ratios of organic fertilizers and chemical fertilizers set up,namely OF0(100% chemical fertilizers),OF25(25% organic fertilizers),OF50(50% organic fertilizers),OF75(75% organic fertilizers),and OF100(100% organic fertilizers). The effects of different fertilization patterns on the agronomic traits,yield,effective component content,nutrient accumulation,and soil physicochemical properties of E. pubescens were determined,and the yield and quality of the medicinal herb were comprehensively evaluated by using the CRITIC weights method. It was found that the herb yield of each treatment group was significantly increased compared with the CK group,although the yield of the groups with both organic fertilizer and chemical fertilizer was slightly lower than that of OF0. However,there was no significant difference,which indicated that the organic fertilizer combined with chemical fertilizer could ensure the herb yield. With the increase in organic fertilizer ratios,the medicinal components epimedin A,epimedin B,and epimedin C showed a tendency of first increasing and then decreasing,with the highest content in the OF25,while icariin showed a rising trend,with the best in the OF100. However,overall,the total flavonol glycosides ABCI accumulated the most in the OF25. The results of the CRITIC method showed that the top three fertilization treatments in terms of the comprehensive scores of the medicinal herb were OF25,OF50,and OF75. Organic fertilizer combined with chemical fertilizer is conducive to improving the soil's fertilizer holding and supply capacity,and the soil indexes are optimal in OF100. The soil enzyme activity is the highest in OF75. Meanwhile,organic fertilizer combined with chemical fertilizer can help the plant's uptake and accumulation of nutrients,and OF25 shows the most obvious effect.By comprehensively considering the influence of different ratios of organic and chemical fertilizers on the yield,effective component content,nutrient accumulation,and other indexes of E. pubescens,it is recommended that a 25% ratio(7 500 kg·hm~(-2)) of organic fertilizers and chemical fertilizers should be used in E. pubescens production in the first year,so as to promote the E. pubescens industry to increase yield and improve quality.

Basalt powder as a promising candidate material for improving the properties of fly ash geopolymer cement

Recently, power plants’ manufacturing processes have evolved, and the amount of fly ash (FA) produced has gradually dropped. After years of investigation, FA has been used with a high rate of success. Therefore, FA, which is needed to manufacture geopolymers, may become more scarce and more expensive. To fill this gap, natural materials can be blended with FA to manufacture geopolymers. In this article, for the first time, a fascinating possibility has emerged for the possible application of natural basalt powder (BP) in FA geopolymer cement. As a partial replacement, several ratios of BP, from 2.5 % to 40 %, were mixed with FA. Geopolymer cement was then produced by activating both neat FA and those combined with BP. An inquiry was carried out to evaluate the influence of different ratios of BP on the flowability, compressive strength, environmental conditions resistance, transport properties, crystalline phases, hydration products, and microstructure of FA geopolymer cement cured in air and water. Regardless of whether the inclusion of BP decreased the flowability, the results showed that the inclusion of 2.5–20 % BP has a positive effect on improving the properties of FA geopolymer cement. The ideal ratio of BP was 10 %. Air curing was found more effective than water curing.

Influence of Different Ratios of DSPE-PEG2k on Ester Prodrug Self-Assembly Nanoparticles for Cell Migration and Proliferation Suppression.

Bufalin (BFL, an active anti-tumor compound derived from toad venom) is limited in its application due to high toxicity and rapid metabolism of the cardiotonic steroid. Ester prodrug self-assembly nanoparticles have shown significant improved effects in addressing the above-mentioned issues. An ester bond was formed between linoleic acid and bufalin to synthesize linoleic acid-bufalin prodrug (LeB). The self-assembly nanoparticles (LeB-PSNs) containing different mass ratios of DSPE-PEG2k and prodrug (6:4, 7:3, 8:2, 9:1 and 10:0) were prepared via co-precipitation method and defined as 6:4-PSNs, 7:3-PSNs, 8:2-PSNs, 9:1-PSNs and LeB-PSNs, respectively. Further, the characterization (particle size, zeta potential, surface morphology and stability) of the nanoparticles was carried out. Finally, we evaluated the impact of different ratios of DSPE-PEG2k on the hydrolysis rate, cytotoxicity, cellular uptake, cell migration and proliferation suppression potential of the prodrug nanoparticles. The linoleic acid-bufalin prodrug (LeB) was successfully synthesized. Upon the addition of DSPE-PEG2k at different weight ratios, both particle size and polydispersity index (PDI) significantly decreased, while the zeta potential increased remarkably. No significant differences in particle size, PDI and Zeta potential were observed among the 9:1, 8:2 and 7:3 PSNs. Notably, the 8:2 (w/w) DSPE-PEG2k nanoparticles exhibited superior stability, hydrolysis and cellular uptake rates, along with efficient cell cytotoxicity, cell migration and proliferation suppression. These findings indicate that DSPE-PEG2k could improve the performance of BFL prodrug nanoparticles, namely enhancing stability and achieving adaptive drug release by modulating the hydrolysis rate of esterase. This study therefore provides more opportunities for the development of BFL application.

Improving the technology of oxidative stabilization of rapeseed oil

The object of the research is the oxidation process of rapeseed oil. Rapeseed oil is used for technical purposes, in the chemical and food industries, in particular, in the production of ecological fuel. Vegetable oils are subjected to oxidative deterioration processes, which are intensified under the conditions of access to oxygen, elevated temperatures, etc. Oxidation products worsen the technological properties and complicate the use of oils in chemical reactions. An important task is to improve the technology of oxidative stabilization of rapeseed oil, which is of great industrial importance. The oxidation process of refined deodorized rapeseed oil according to DSTU 8175 (CAS Number 120962-03-0) at a temperature of 110 °C was studied by the method of differential scanning calorimetry. The influence of different ratios of antioxidants (tocopherol, butylhydroxyanisole and butylhydroxytoluene) in the mixture on the oil induction period was determined. The total concentration of the antioxidant mixture in each experiment was 0.02 %. The induction period of the initial oil is 408.48 min. The rational ratios of the components of the antioxidant mixture were determined: tocopherol: butylhydroxyanisole (75:25) %; tocopherol: butylhydroxyanisole: butylhydroxytoluene (66.67:16.67:16.67) %. The corresponding oil induction periods were 579.75 min. and 561.55 min. The physico-chemical indicators of rapeseed oil after 12 months of storage at a temperature of (20±2) °C in its original form and with the addition of the developed antioxidant mixtures were determined. The peroxide value of the oil was 12.5, 4.59, 6.45 ½ O mmol/kg, respectively. The research results allow improving the technology of oxidative stabilization of rapeseed oil at elevated and standard temperatures. This will help to extend the oil shelf life, more efficiently and rationally use the oil in various areas

Transition metal modified Al2O3 mesoporous nanospheres for catalysis of organic reactions

The performance of metal oxide-based catalysts are usually determined by their characteristics such as material composition, morphology, and surface/interface properties. Therefore, rational design of metal oxide-based catalysts with special surface/interface characteristics and porous microstructure still needs further research. In this work, a facile two-step solvothermal-annealing method is developed for the synthesis of transition metal (TM) modified Al2O3 (TM-Al2O3, TM = Cu, Fe, Ni, Co) nanospheres. The influences of different ratios of solvents (e.g., water and glycerol) on the morphology and particle size of the nanocatalysts are explored. Benefitting from the nano-spherical morphology and unique mesoporous structure, the representative catalyst (i.e., Cu-Al2O3) exhibits favorable catalytic performance in 4-nitrophenol reduction and benzyl alcohol oxidization reactions. The turnover frequency of Cu-Al2O3 is high up to 35.9 min−1 for the reduction of 4-nitrophenol, which is higher than that of its counterparts (i.e., Fe-Al2O3, Ni-Al2O3, and Ni-Al2O3) and many recently reported Al2O3-based catalysts. Moreover, the pH of the reaction system is regulated to enhance the catalytic efficiency in selective oxidization of benzyl alcohol by an additive addition strategy. These results suggest that the nano-spherical and mesoporous morphology is indeed effective for the activity enhancement of TM-Al2O3 catalysts. The same catalyst designing concept and performance regulation strategy may be extended to other TM-modified metal oxide systems, making it possible to tune the catalytic behavior for various chemical reactions.

P2/O3 biphase integration promoting the enhancement of structural stability for sodium layered oxide cathode

O3-type sodium layered oxides have garnered significant attention as highly promising candidates for sodium ion batteries due to their high theoretical capacity. However, they often encounter challenges associated with complex and irreversible phase transitions and sluggish kinetics. To overcome these issues, herein we integrate the O3-type phase with the P2-type phase and systematically investigate the influence of different ratios of P2 phase in O3-type NaxLi0.05Mn0.55Ni0.3Cu0.075Mg0.025O2 pentanary layered oxides on the electrochemical performance by tuning the sodium contents. The LMC3-P2/O3-32 with optimized P2 phase ratio of 32.3 % exhibits a high reversible capacity of 157.0 mAh g−1 at a rate of 0.2C and excellent capacity retention rate of 63.5 % after 1000 cycles at 10C. The LCM3-P2/O3-32 also demonstrates good cycle life and rate capability in full cells when coupled with a hard carbon anode. In situ X-ray diffraction analyses confirm that the detrimental phase transformations to Na-poor O1 phase and the irreversible phase transitions occurred in the pure O3 cathode can be effectively suppressed in the P2/O3 biphasic cathode. The less Jahn-Teller active ions, enhanced phase transition reversibility and improved diffusion kinetics of Na+ ions are responsible for the improved cyclability and rate capability in the P2/O3 nanoscale intergrowth cathode. Our work shed light on the leverage of P2 and O3 phases through phase integration in layered oxides cathodes, which can serve as a guideline for the further development of high-performance cathode materials for advanced sodium ion batteries.

Effects of taro [Colocasia esculenta (L.) Schott] slices on nutritional quality, sensory quality, and shelf life of Chinese pickled and steamed pork belly.

This study aimed to investigate the influence of different ratios of taro slices (TS) on the nutritional quality, sensory quality, and shelf life of Chinese pickled and steamed pork belly (CPSPB). The study examined various aspects of CPSPB, including its proximate components, fat oxidation, fatty acid composition, protein hydrolysis, oxidation reaction, and induction period (IP). Additionally, the sensory quality and texture analysis were compared simultaneously. The results showed that the addition of TS to CPSPB significantly improved water and lipid loss (p < 0.05), increased the unsaturated/saturated ratio of fatty acids, and reduced lipid and protein oxidation. Additionally, the incorporation of TS extended the IP and enhanced the shelf life of CPSPB. Particularly, the addition of a specific amount of TS (60%) to CPSPB resulted in the highest organoleptic quality. Therefore, these results emphasize the positive impact of TS on the overall quality of CPSPB, highlighting its potential to enhance the nutritional value, sensory attributes, and shelf life.

Composite of iron phthalocyanine and reduced graphene oxide with low temperature hydrothermally grown Ti3C2Tx Mxene for ORR catalytic application

In this paper, Ti3C2Tx MXene was successfully prepared by a mild and environment-friendly low-temperature hydrothermal method. On this basis, the compsites FePc-M-rGO consisting of iron phthalocyanine (FePc), Ti3C2Tx MXene and reduced graphene oxide (rGO) were prepared through simple mixing and used as catalysts for oxygen reduction reaction (ORR). The materials were characterized by SEM, XRD and other methods. The effects of raw material ratio, hydrochloric acid concentration, reaction temperature and reaction time on the properties of Ti3C2Tx were studied in detail. Compared with hydrofluoric acid (HF) etching method, the Ti3C2Tx prepared by low-temperature hydrothermal method has larger layer spacing, more complete crystal structure, larger specific surface area and better conductivity. The influences of different ratios of each component of FePc-M-rGO on the ORR catalytic performances were investigated. Mainly attributed to the improvement of self stacking and uniform adhesion of FePc between Ti3C2Tx layer and graphene nanosheets, the optimized composite material has better ORR activity than commercially available Pt-C catalysts and has good application prospects. This work provides a new approach for the rapid and effective preparation of Ti3C2Tx Mxene, and provides new ideas for the design of non-noble metal catalysts for ORR.

Interfacial properties of PPBES/CF composites reinforced by ammonified carbon fibers through thiol-ene click reaction

Our previous work has shown that the amino group is beneficial to improve the interface properties of PPBES/CF composites. However, the existing methods for introducing amino groups have many reaction steps, long reaction time and harsh reaction conditions. A one-step efficient click reaction can effectively avoid the above disadvantages. In this paper, 2-aminoethanethiol (AET) was grafted to CF via a thiol-ene click reaction. The reaction time has been reduced from over 9 h to just 1.5 h. The successful introduction of amino group into CF was testified by FTIR, Raman and XPS. The influence of different ratios of CF:AET on the interfacial properties of the composites was studied emphatically. When CF: AET was 1:3 (T3), the composite exhibited optimal mechanical properties. The ILSS and flexural strength of the resulting composite increased by 24.45% and 33.1%, respectively. The Tg of the PPBES/T3 composite was increased to 242 °C as verified by DMA.

Influence of Different Industrial Waste Residues on Engineering Properties of High Liquid Limit Soil and Its Microscopic Mechanism

High liquid limit soil has unfavorable engineering geological characteristics, such as strong disintegration, dry shrinkage and easy cracking, and easy uplift when encountering water, which will cause various problems to the engineering. At present, the relationship between the physical and mechanical properties of high liquid limit soil and the characteristics of water-soil interaction is still not clear enough. In this study, the high liquid limit soil of Zhanjiang Avenue was selected to explore the influence of different ratios of three kinds of industrial waste residues (blast furnace slag, carbide slag, and tailing sand) on the high liquid limit soil. Aiming at the common adverse engineering geological phenomena of high liquid limit soil, such as easy disintegration, dry shrinkage crack, and easy uplift in water, the effects of different industrial waste residues on the water-soil interaction characteristics of high liquid limit soil are explored through disintegration and crack tests. In addition, the effects of different kinds and ratios on the free expansion rate, pH, unconfined compressive strength, and shear strength parameters of high liquid limit soil were studied. The improvement mechanism of different industrial waste residues on the engineering properties of high liquid limit soil is discussed in terms of mineral composition and microstructure. Based on the experimental results of this study and considering the cost and engineering practice, it is suggested that the modified carbide slag optimal ratio of high liquid limit soil of Zhanjiang Avenue is 8%. The results can provide certain guidance for the improvement and application of different industrial waste residues on high liquid limit soil to achieve the effect of sustainable development.

Compressive strength and heavy metal adsorption of cork residue, natural zeolite, and low-grade metakaolin-based geopolymers

Low-grade Portuguese metakaolin (MK), natural zeolite and waste cork residue were tested as replacements for commercial MK-based geopolymers in terms of compressive strengths and heavy metal adsorption properties. The low-grade kaolins were sourced from the Alvarães (A) and Barqueiros (B) deposits in Portugal. Various sets of geopolymers were obtained by replacing MK with up to 75 wt% zeolite and adding cork residue, 20 wt% of the total powder mass, to all geopolymers (A25-C, B25-C – 25 % MK 75 % zeolite; A50-C, B50-C – 50 % MK 50 % zeolite; A75-C, B75-C − 75 % MK 25 % zeolite; A100-C, B100-C – 100 % MK). To keep the environmental footprint of the chemicals to a minimum, the Na2O/Al2O3 and SiO2/Al2O3 molar ratios were kept at 1. Geopolymers were characterized to understand the influence of different ratios of MK and zeolite and also cork residue incorporation on their structure and surface morphology. The crystallinity of the geopolymers increased with increasing zeolite in the structure. The addition of cork residue appeared to yield compact geopolymer materials. Maximum compressive strengths of 26.7 and 25.3 MPa were obtained for Alvarães and Barqueiros MK geopolymers, respectively, with only MK and cork residue in the structure, indicating that zeolite addition does not improve the compressive strength values. The adsorption of divalent Pb2+, Cd2+, Cu2+ and Zn2+ cations and the trivalent Cr3+ cation indicated high adsorption capacities of Portuguese MK-based geopolymers. The adsorption of the cations is dependent on the composition of the geopolymers yielding selective adsorption. The geopolymers adsorb Pb2+ in the highest amounts followed by Cd2+ and Cu2+. Zn2+ is adsorbed in slightly lower amounts and Cr3+ is adsorbed in the least amounts. The cork residue and zeolite appear to significantly affect the structure, morphology and properties of geopolymers Overall, the Portuguese MK geopolymers containing cork residue can be effective replacements for commercial MK geopolymers.

Using Mathematical Models to Study the Influences of Different Ratios of Chemical Nitrogen, Phosphorus, and Potassium on the Content of Soluble Protein, Vitamin C, and Soluble Sugar in Melon.

The current fertilizer recommendations for melon plantation have many limitations and exhibit deficiencies regarding future development. Therefore, in this study, the optimal quantities of fertilizer, in terms of the effects of single factors and interaction effects, are studied. There were significant interaction effects between N and P, N and K, P and K; the contents of soluble protein, vitamin C (Vc), and soluble sugar in melon could be improved using the optimal fertilization ratios. The optimal ratio of N:P:K was 2.33:1:3.85, with the amounts of N, P2O5, and K2O, respectively, being 157.5, 67.58, and 260.38 kg/hm2, yielding 8.73 g/kg of soluble protein in melon. The optimal ratio of N:P:K was 2.03:1:3.36, with amounts of N, P2O5, and K2O being 157.50, 77.40, and 260.38 kg/hm2, respectively, yielding 25.32 g/kg Vc content in melon. Finally, the optimal ratio of N:P:K was 1.53:1:3.36, with the amounts of N, P2O5, and K2O being 118.07, 77.40, respectively, and 260.38 kg/hm2, yielding 13.34% soluble sugar content in melon.

ZIF – 67 derived hybrid CuCo2S4@MoS2 catalyst for efficient electrocatalytic hydrogen evolution reaction

Developing hybrid metal sulfide electrocatalyst with excellent hydrogen evolution reaction (HER) catalytic performance and stability is vital to its commercial applications. Herein, hybrid CuCo2S4@ MoS2 catalysts were designed with CuCo2S4 synthesized by using ZIF-67 as a template and externally decorated with MoS2. The hybrid catalysts (denoted as C@M-0.5, C@M ​− ​1, C@M ​− ​2) show improved catalytic activity than those of MoS2 and CuCo2S4 due to large surface area and the interface between nanoflower-like MoS2 and three-dimensional interconnected lamellar stacked CuCo2S4, which boost charge transport capability and improve the HER kinetic process. The influences of different ratio of CuCo2S4 to MoS2 on the electrocatalytic activity are investigated in detail. Specifically, C@M ​− ​1 exhibit the best HER performance with an overpotential of 143 ​mV@ 10 ​mA/cm2, a Tafel slope of 45.2 mV/dec and satisfactory long-time stability. This work rationally designs hybrid CuCo2S4@MoS2 catalyst to preserve the merits of using the ZIF-67 as a template and make use of the synergistic coupling effects between CuCo2S4 and MoS2, which can be extended to synthesize other catalysts in different energy conversion fields.

Facile Synthesis of Hafnium Oxide Nanoparticle Decorated on Graphene Nanosheet and Its Photocatalytic Degradation of Organic Pollutants under UV-Light Irradiation

The HfO2 nanoparticles and the nanocomposites of HfO2-graphene (10, 30, and 50 wt%) were prepared via precipitation and simple mixing method. The XRD pattern confirmed the presence of monoclinic HfO2 and hexagonal graphene in the nanocomposite. Raman spectroscopy studies revealed the formation of HfO2-graphene nanocomposite. According to SEM and TEM images the HfO2, NPs are spherical, and their size is less than 10 nm, anchored on the surface of the graphene sheets. The EDX spectrum shows carbon, oxygen, and HfO2 and reveals the formation of the HfO2-graphene nanocomposite. The UV-vis absorption spectra show the optical properties of synthesized HfO2-graphene nanocomposite. The study examines the influence of different ratios of the addition of graphene on the photocatalytic activity of HfO2-graphene. It was found that the HfO2-graphene (50 wt%) 40 mg nanocomposite exhibits enhanced photocatalytic activity than the bare HfO2 towards the methylene blue photodegradation, an aromatic pollutant in water under UV light irradiation, which can be applied optimally for individually wastewater management system. The HfO2-graphene (50 wt%) photocatalyst degrades 81 ± 2% of tetracycline in 180 min, implying that tetracycline can be degraded more efficiently under UV light. The enhancement in photocatalytic activity under UV light illumination can be attributed to the effective separation of photogenerated electrons, inhibiting recombination in the HfO2-graphene composite.

Experimental evaluation of the role of inorganic phosphorus for terrestrial carbon degradation in stream hyporheic zones

Abstract The hyporheic zone (HZ) is a hotspot of carbon processing in stream ecosystems as a consequence of the mixing of organic matter and nutrients from ground water and surface waters. However, major knowledge gaps exist regarding the drivers of microbial activity and carbon processing in the HZ among stream ecosystems with different carbon sources and sediment properties. We investigated the impact of algal dissolved organic matter (DOMalgal) and inorganic phosphorus (P) on the degradation of soil DOM (DOMsoil) by hyporheic microorganisms in two laboratory experiments. In our first experiment, we explored the influence of different ratios of DOMalgal to DOMsoil with and without P additions on microbial respiration and DOM composition in laboratory hyporheic microcosms under oxic conditions. Here, we used glass beads colonised by stream microorganisms resembling a pristine stream system. As the addition of DOMalgal increased P concentrations, we added P to adjust the P concentrations to the same level of the pure DOMalgal in a second batch. In our second experiment, we determined the aerobic microbial respiration of HZ‐sediments from 20 streams along a land‐use gradient in Austria incubated with DOMsoil. Again, we performed the experiments with and without P additions to see whether effects on microbial respiration depended on the ambient P concentrations of the streams. Aerobic microbial respiration in the hyporheic microcosms decreased with increasing DOMsoil proportions. When P concentrations were adjusted to the P level of the DOMalgal, aerobic microbial respiration rates were similar between the different DOM mixtures in the microcosms, mainly stimulating the degradation of humic‐like DOM fractions. This highlights the stimulating effects of the P additions on hyporheic microbial respiration and humic‐like DOM degradation in pristine streams. However, P additions caused a significant increase in microbial respiration in only one of 20 natural HZ‐sediments, suggesting that aerobic microbial respiration rates rarely were controlled by P availability in the investigated streams. We conclude that nutrient pulses can, but do not necessarily, stimulate microbial activity and terrestrial carbon degradation in the HZ of streams. Nevertheless, at low ambient nutrient concentrations (i.e., in pristine streams) terrestrial carbon degradation in the HZ can be accelerated when nutrient pulses occur, which has consequences for CO2 outgassing and the organic matter quality in the stream and its export to downstream sections.

The influence of different ratio of Sn4+ and Bi3+ on n-p SnO2/α∼ Bi2O3 composite structure and its photocatalytic properties by solid phase synthesis

In this study, a novel n-p SnO2/α∼Bi2O3 composites were synthesized by the convenient and rapid in-situ solid-phase reaction synthesis. The different influence of ratios: n (Sn: Bi) = 2/1, 3/1, 1/1, 1/2 and 1/3 on the crystal shape, microstructure, specific surface area, optical absorption properties of the material and the separation ability of photocarriers were discussed. The study shows that: compared with pure SnO2, the light absorption boundary of all the composites have been widened to the visible light region, the larger the ratio of Sn in the sample, the more conducive it is to absorbing the visible light. However, greater ratio of Sn4+ ions in the sample will lead to a decrease in the separation ability of photo electrons and holes. Of which n(Sn: Bi) = 2/1 composite, photoelectrons and holes have the strongest separation ability. The Rhodamine B (Rh. B) solution can be almost completely decolorized within about 30 minutes under 400W halide light irradiation. The chemical reaction mechanism in the sample synthesis process was discussed in detail. This study not only synthesized excellent n-p SnO2/α∼Bi2O3 photocatalytic composites, but also provides references for in-situ synthesis of other semiconductors.

The influence of different ratio of Ar and C[formula omitted] gases and ion bombardment on the growth rate and sp3 bonds content in DLC-coatings synthesized in RF discharge

The radio-frequency discharge growth of diamond-like carbon coatings from the Ar + C6H6 gas was theoretically analyzed with the aim to evaluate the role of Ar+ ions and C6H6+ ionized molecules bombardment on the growth rate and sp2/sp3 carbon phase composition. It has been shown that the growth rate changes nonlinearly with the increase of argon content in the gas. Firstly, it increases from 1.9 μm/h at PAr/(PAr+Pbenzol)=0.033 up to 2.15 μm/h at PAr/(PAr+Pbenzol)=0.5 with further rapid decrease down to 0.57 μm/h at PAr/(PAr+Pbenzol)=0.967. By using theoretical calculations as well as experimental methods it has been shown that sp3 content in the coatings increases within the range 0.31…0.41 with increase in the relative partial pressure of argon.

Hydroxypropyl methylcellulose films reinforced with cellulose micro/nanofibrils: study of physical, optical, surface, barrier and mechanical properties

Abstract The accumulation of petroleum products causes damage to ecosystems, which can be avoided with cellulose-based products. The influence of different ratios of cellulose micro/nanofibrils (MFC/NFC) on the properties of hydroxypropyl methylcellulose (HPMC) films was evaluated. Films were prepared using proportions of 0, 25, 50, 75 and 100 % (w/w) of MFC/NFC from Pinus sp. in relation to HPMC. Physical, barrier, surface, optical, morphological and mechanical properties were evaluated. Solids content, basis weight and density values increased with higher amount of MFC/NFC and thickness and porosity were reduced. SEM images showed that films with more than 50 % MFC/NFC had a more granular surface, which decreased transparency from 80 to 65 %. Water vapor penetration did not differ between films and degradation in water was reduced from 40 to 5 % with MFC/NFC addition. There were no differences in contact angle and wettability, but all films showed high resistance to fat penetration. Films with MFC/NFC content between 75 and 100 % showed higher values for tensile strength (50 to 65 MPa) and Young’s modulus (6 to 10 MPa) and lower elongation at break (1 to 2 %). The experimental results indicated that films with MFC/NFC content above 50 % have potential to be used as packaging material.