Mixing Ratio Research Articles

Effect of carbon dioxide mineralization curing on mechanical properties and microstructure of Portland cement–steel slag–granulated blast furnace slag ternary paste

To investigate the synergistic effects of steel slag (SS) and granulated blast furnace slag (GBFS) on cementitious systems during carbon dioxide (CO2) mineralization curing. Ternary paste specimens containing SS, GBFS, and Portland cement (PC) were prepared to analyze the influence of drying pre-treatment time and SS–GBFS mixing ratios on mechanical properties, CO2 fixation rate, and microstructure evolution. Results emphasize the significance of appropriate drying pre-treatment in enhancing mineralization degree and compressive strength. At 60 °C drying pre-treatment temperature, extending drying pre-treatment time up to 12 h enhances both compressive strength and CO2 fixation rate. However, beyond 12 h, a decline is observed in both parameters. Moreover, under the optimal drying pre-treatment time, the compressive strength of ternary paste specimens post-mineralization increases with higher SS content, with SS exerting a more pronounced positive effect on CO2 fixation rate and compressive strength compared to GBFS. After 4 h of mineralization curing, specimens with 50% SS and 10% GBFS demonstrate a 13.16% increase in compressive strength and a 9.16% increase in CO2 fixation rate compared to specimens with 10% SS and 50% GBFS. Microscopic test results reveal that the primary crystalline product in ternary paste specimens after mineralization is calcite, with traces of aragonite. The SS–GBFS mixing ratio has minimal effect on the type of reaction products but has a predominant influence on the total content and crystallinity of calcarea carbonica.

Adsorption behavior of NH4+ and Mg2+ at kaolinite surfaces: Effect of the ion concentration, NH4+/Mg2+ mixing ratio, and layer charge

AbstractThe adsorption behavior of NH4+ and Mg2+ at kaolinite surfaces was investigated by using molecular dynamics (MD) simulations, considering the factors such as ion concentration, NH4+/Mg2+ mixing ratio, and layer charge of kaolinite. The results showed that the increase in ion concentration did not affect the adsorption modes of NH4+ and Mg2+ ions but promote the increase in the adsorption capacity. The total adsorption capacities of Mg2+ and NH4+ were 3.25 × 10−6 and 2.85 × 10−6 μmol·mm−2 at the ion concentration of 1.5 mol·L−1, respectively. When NH4+ and Mg2+ were co‐adsorbed, they could inhibit the adsorption of each other at the surface of kaolinite, except that the inner‐sphere (IS) adsorption of NH4+ at aluminum hydroxyl (Al–OH) surface could be enhanced by the presence of Mg2+. Both NH4+ and Mg2+ tended to adsorb at the siloxane (Si–O) surface of kaolinite rather than Al–OH surface. When layer charge occurred in kaolinite, a small number of Mg2+ began to adsorb in the IS complexes at 1.7 and 2.3 Å above the Al and O atoms of the lattice‐substituted tetrahedra of the Si–O surface, and at 1.7 Å above the hexahedra of the Al–OH surface. However, most of NH4+ were adsorbed in IS complexes at 1.7 Å above the center of the oxygen six‐membered ring of the Si–O surface and above the hexahedron of the Al–OH surface. The adsorption capacity of Mg2+ changed little with the increase of layer charge density, while the IS and total adsorption capacity of NH4+ increased significantly.

An improved and extended parameterization of the CO2 15 µm cooling in the middle and upper atmosphere (CO2_cool_fort-1.0)

Abstract. The radiative infrared cooling of CO2 in the middle atmosphere, where it emits under non-local thermodynamic equilibrium (non-LTE) conditions, is a crucial contribution to the energy balance of this region and hence to establishing its thermal structure. The non-LTE computation is too CPU time-consuming to be fully incorporated into climate models, and hence it is parameterized. The most used parameterization of the CO2 15 µm cooling for Earth's middle and upper atmosphere was developed by Fomichev et al. (1998). The valid range of this parameterization with respect to CO2 volume mixing ratios (VMRs) is, however, exceeded by the CO2 of several scenarios considered in the Coupled Climate Model Intercomparison Projects, in particular the abrupt-4×CO2 experiment. Therefore, an extension, as well as an update, of that parameterization is both needed and timely. In this work, we present an update of that parameterization that now covers CO2 volume mixing ratios in the lower atmosphere from ∼0.5 to over 10 times the CO2 pre-industrial value of 284 ppmv (i.e. 150 to 3000 ppmv). Furthermore, it is improved by using a more contemporary CO2 line list and the collisional rates that affect the CO2 cooling rates. Overall, its accuracy is improved when tested for the reference temperature profiles as well as for measured temperature fields covering all expected conditions (latitude and season) of the middle atmosphere. The errors obtained for the reference temperature profiles are below 0.5 K d−1 for the present-day and lower CO2 VMRs. Those errors increase to ∼1–2K d−1 at altitudes between 110 and 120 km for CO2 concentrations of 2 to 3 times the pre-industrial values. For very high CO2 concentrations (4 to 10 times the pre-industrial abundances), those errors are below ∼1 K d−1 for most regions and conditions, except at 107–135 km, where the parameterization overestimates them by ∼1.2 %. These errors are comparable to the deviation of the non-LTE cooling rates with respect to LTE at about 70 km and below, but they are negligible (several times smaller) above that altitude. When applied to a large dataset of global (pole to pole and four seasons) temperature profiles measured by MIPAS (Michelson Interferometer for Passive Atmospheric Spectroscopy) (middle- and upper-atmosphere mode), the errors of the parameterization for the mean cooling rate (bias) are generally below 0.5 K d−1, except between 5×10-3 and 3×10-4 hPa (∼85–98 km), where they can reach biases of 1–2 K d−1. For single-temperature profiles, the cooling rate error (estimated by the root mean square – rms – of a statistically significant sample) is about 1–2 K d−1 below 5×10-3 hPa (∼85 km) and above 2×10-4 hPa (∼102 km). In the intermediate region, however, it is between 2 and 7 K d−1. For elevated stratopause events, the parameterization underestimates the mean cooling rates by 3–7 K d−1 (∼10 %) at altitudes of 85–95 km and the individual cooling rates show a significant rms (5–15 K d−1). Further, we have also tested the parameterization for the temperature obtained by a high-resolution version of the Whole Atmosphere Community Climate Model (WACCM-X), which shows a large temperature variability and wave structure in the middle atmosphere. In this case, the mean (bias) error of the parameterization is very small, smaller than 0.5 K d−1 for most atmospheric layers, reaching only maximum values of 2 K d−1 near 5×10-4 hPa (∼ 96 km). The rms has values of 1–2 K d−1 (∼20 %) below ∼2×10-2 hPa (∼80 km) and values smaller than 4 K d−1 (∼2 %) above 10−4 hPa (∼105 km). In the intermediate region between ∼5×10-3 and ∼2×10-4 hPa (85–102 km), the rms is in the range of 5–12 K d−1. While these values are significant in percentage at ∼5×10-3–5×10-4 hPa, they are very small above ∼5×10-4 hPa (96 km). The routine is very fast, taking (1.5–7.5) ×10-5 s, depending on the extension of the atmospheric profile, the processor and the Fortran compiler.

Response of Soil Microbial Community Structure and Diversity to Mixed Proportions and Mixed Tree Species in Bamboo–Broad-Leaved Mixed Forests

Bamboo and broad-leaved mixed forests have been widely recognized for their advantages in maintaining ecological balance, improving soil fertility, and enhancing biodiversity. To understand the effects of mixed broad-leaved tree species and mixing ratios on soil microbial communities in bamboo and broad-leaved mixed forests, we quantified the structure and diversity responses of soil microbial communities to tree species and mixing ratios using high-throughput sequencing of the 16 S rRNA gene. Three bamboo and broad-leaved tree mixed forests were studied, including bamboo–Castanopsis chinensis Hance mixed forest (CCB), bamboo–Alniphyllum fortune (Hemsl.) Makino mixed forest (AFB), and bamboo–Choerospondias axillaris (Roxb.) B. L. Burtt & A. W. Hill mixed forest (CAB). We assessed the impact of tree species and mixing ratios on soil microbial communities by measuring soil properties and the diversity and composition of soil microbes. The results indicate that soil properties and the diversity and composition of microbial communities are highly dependent on broad-leaved tree species in mixed forests. The mixing ratios had a more pronounced effect on microbial diversity than on richness. In CAB, diversity peaked at mixing ratios of 10%–20% and 20%–40%. The presence of broad-leaved trees significantly altered the relationships among soil bacteria, with CAB showing the highest stability, likely due to the increased diversity and quantity of litter from Choerospondias axillaris. Our results show that the choice of broad-leaved tree species and their mixing ratios significantly influence soil microbial diversity and composition in bamboo–broad-leaf mixed forests. An optimal mixing ratio in CAB can maximize bacterial diversity and stability, providing insights for forest management and promoting ecosystem health and sustainability.

Optimization and uncertainty analysis of Co-combustion ratios in a semi-isolated green energy combined cooling, heating, and power system (SIGE-CCHP)

This study delved into the integration of biomass gas and natural gas within a Combined Cooling, Heating, and Power (CCHP) system. A Semi-Isolated Green Energy CCHP (SIGE-CCHP) model was devised to scrutinize the performance of co-firing equipment across diverse optimization objectives, while manipulating the proportions of natural gas and biomass gas as inputs. Findings revealed that escalating the share of biomass gas led to a reduction in carbon emissions but triggered an escalation in operational and maintenance costs. However, at an optimal mixing ratio of 1:1, carbon emissions exhibited marginal increments, coupled with a substantial decrease in operational and maintenance expenses. Notably, when prioritizing operational and maintenance costs, the system exhibited optimal performance, resulting in a notable 26.76 % cost reduction. Conversely, when prioritizing carbon emissions, the system metamorphosed into a carbon sequestration entity, with a maximal capacity to absorb 2021.86 kg of carbon dioxide. This study furnishes theoretical underpinnings for optimizing the operation of co-firing equipment, augmented by a sensitivity analysis aimed at intuitively elucidating the repercussions of varying mixing ratios on the system.

Numerical investigation of CH4/H2/air micro-mixing combustion flow in a micro gas turbine combustor with different head-end structures

In order to investigate the premixed combustion characteristics of CH4/H2/air in a micro-mixing combustor, the effects of different micro-mixing head-ends (HE1, HE2, HE3) and hydrogen mixing ratios on the temperature distribution, heat transfer process, emission characteristic, flames shape are analyzed. The results show that compared with swirl head-end combustion, the micro-mixing combustion performance is better. Among the three head-ends, HE3 has the best combustion characteristics and stable flames. The temperature distribution in the high-temperature zone is uniform, and low-temperature zone is concentrated near the jet, which can suppress the flashback. The velocity and temperature gradient near the central axis of jet streams show a strong synergistic effect. The flames are plume shaped and flames stability is mainly influenced by the H2 combustion process. Increasing the jet diameter, decreasing the jet spacing and increasing the hydrogen mixing ratio all contribute to the flames stability, but these three methods can stabilize the flames by affecting fluid Reynolds number, interaction between small flames and combustion rate, respectively. Moreover, small jet diameter and high hydrogen mixing ratio can reduce OTDF, which contributes to improve outlet temperature uniformity.

Research on Formulation and Evaluation of Floating Microspheres

The purpose of this study is to design and evaluate a floating multipart oral delivery system for diltiazem hydrochloride that can provide sustained release. The aim of the work is also to study various parameters that influence the behaviour of floating multiparticles in an oral dosage form. Floating microspheres were prepared by a non-aqueous emulsifying solvent evaporation technique using ethyl cellulose and Eudragit RS-100 asthe rate-controlling polymer. In vitro activity was evaluated using standard pharmacopoeia and other tests such as drug-polymer compatibility, (%)yield, particle size analysis, drug entrapment efficiency, surface topography, in vitro buoyancy and release studies. The results show that the mixing ratio of the components in the organic phase affected the size, size distribution (199-320 µm), drug concentration(59-84%), percent yield (57-77%) and drug. Liberation microsphere (45-99aftern12 hours) and swimming time > 12 hours. The best results were obtained in the ratio drug: polymer Eudragit RS-100 (1:3). Good in vitro floating behaviour was observed in most cases, and various drug release patterns could be achieved by varying the polymer ratio, which was optimized to match the target release profile. Stability studies showed no significant change in the drug content of the formulation even after 3months. The data obtained in this study therefore suggest a floating dose of micro particles

Fuelling of deuterium–tritium plasma by peripheral pellets in JET experiments

A baseline scenario of deuterium–tritium (D–T) plasma with peripheral high-field-side fuelling pellets has been produced in JET in order to mimic the situation in ITER. The isotope mix ratio is controlled in order to target the value of 50%–50% by a combination of tritium gas puffing and deuterium pellet injection. Multiple factors controlling the fuelling efficiency of individual pellets are analysed, with the following findings: (1) prompt particle losses due to pellet-triggered edge-localised modes (ELMs) are detected, (2) the plasmoid drift velocity might be smaller than that predicted by simulation, (3) post-pellet particle loss is controlled by transient phases with ELMs.The overall pellet particle flux normalised to the heat flux is similar to that in previous pellet fuelling experiments in AUG and JET.

High aspect ratio SiO2/SiN (ON) stacked layer etching using C3HF5, C4H2F6, and C4H4F6

Abstract High aspect ratio SiO2/SiN (ON) stacked layer etching using hydrofluorocarbon gases was conducted with various ratios of H, F, and C to achieve higher etching rates and precise profile control. The experimental gases were C3HF5, C4HF5, C4H2F4, C4H2F6, C4H4F6 and C5H2F10. The oxygen gas flow rate and mixing ratio were optimized to maximize mask selectivity while avoiding clogging at the top of the mask. For comparison, C4F6/CH2F2/Ar/O2, and C4F6/C4F8/CH2F2/Ar/O2 were used as reference gas mixtures. The initial screening narrowed the candidate pool to 3 gases: C3HF5, C4H2F6, and C4H4F6. At equivalent power, the C3HF5 condition achieved a 15% faster ON etch rate, and C4H2F6 achieved a 9% faster ON etch rate compared to the reference condition. Only C4H4F6 showed a worse ON etch rate than the reference (~33%) due to severe mask clogging. Furthermore, C3HF5 achieved a 29% faster ON etch rate under high power conditions. It also achieved a 57% faster ON etch rate without excessively compromising selectivity or bow CD expansion after optimization. We report detailed comparisons of etch rate and clogging while controlling the CD profile in the ON stack process.

Photoacoustic method for measuring the elasticity of polydimethylsiloxane at various mixing ratios

Measuring elasticity without physical contact is challenging, as current methods often require deconstruction of the test sample. This study addresses this challenge by proposing and testing a photoacoustic effect-based method for measuring the elasticity of polydimethylsiloxane (PDMS) at various mixing ratios, which may be applied on the wide range of applications such as biomedical and optical fields. A dual-light laser source of the photoacoustic (PA) system is designed, employing cross-correlation signal processing techniques. The platform systems and a mathematical model for performing PDMS elasticity measurements are constructed. During elasticity detection, photoacoustic signal features, influenced by hardness and shapes, are analyzed using cross-correlation calculations and phase difference detection. Results from phantom tests demonstrate the potential of predicting Young's modulus using the cross-correlation method, aligning with the American Society for Testing and Materials (ASTM) standard samples. However, accuracy may be affected by mixed materials and short tubes. Normalization or calibration of signals is suggested for aligning with Young's coefficient.

Anaerobic Co-Digestion of Food Waste and Microalgae at Variable Mixing Ratios: Enhanced Performance, Kinetic Analysis, and Microbial Community Dynamics Investigation

Anaerobic Co-Digestion of Food Waste and Microalgae at Variable Mixing Ratios: Enhanced Performance, Kinetic Analysis, and Microbial Community Dynamics Investigation

Effect of seed husk waste powder on the PLA medical thread properties fabricated via 3D printer

Abstract With the increasing use of medical equipment, threads are the catchy choice for medical personnel to solve wound closures. One raw material used in medical surgical threads is polylactic acid (PLA), which is appropriate for its environmentally friendly and biodegradable properties. However, the weakness of PLA is in mechanical properties. This work used extrusion-based three-dimensional (3D) printing (fused deposition modeling) to fabricate medical threads from PLA. The effect of adding seed husk waste powders (SHWPs) to PLA filament (1.75 mm) and its manufacture by the 3D printer was studied. Four types of SHWP waste plants were used: pistachio, coffee, chestnuts, and walnuts crushed and milled by ball-milling after chemical processing and drying. The structural, particle size, and physical properties of the prepared powders were studied. The results of SHWPs show that the particle size is near the nano-size range of NPs and of low density. Different SHWP weight mixing ratios (5–15 wt%) were coated to PLA threads (0.4–0.45 µm) by grafting to study the mechanical (surface hardness and roughness) properties. The result shows that 15 wt% was the best ratio that combined the mechanical properties. The coated layer thickness was less than 5 µm. This ratio was adopted to fabricate grafted PLA and SHWPs/PLA medical threads by 3D printing with a radius of 400 ± 5 µm. The structural and biological properties of the fabricated medical threads were investigated. The results of SHWP-coated PLA show a significant improvement in structural and physical properties besides the mechanical properties. The results adopted this percentage from thread SHWP-coated PLA for medical applications, creating a new benefit for agricultural SHW and accelerated healing.

Binary Nematic Liquid Crystals Mixture with Enhanced Electro-Optics Properties for Photonic Applications

Purpose: In this work, we mix two simple nematic liquid crystals (NLCs) and investigated the binaryNLCs mixtures of 7CB/PCH5 of different mixing ratios. Methodology: The pure liquid crystals 7CB and PCH5 and binary mixtures of them of high temperature stability were thermally analyzed by differential scanning calorimetry. The mixture 7CB/PCH5:30/70 wt% has the highest thermal stability with a nematic-isotropic (N-I) transition temperature at 50oC. The electrooptic properties of 7CB, PCH5, and the mixture 7CB/PCH5:30/70 wt% at room temperature were also investigated using an amplitude modulated electric signal (1 kHz - 100 Hz) by increasing diving peak voltage from 0 V to 10 V. The threshold volage is relatively reduced for the binary mixture in comparison to that value for PCH5. In comparison to the pure LCs, the mixture 7CB/PCH5:30/70 wt% has the fastest response times of values 2.36 ms total time response, 0.41 ms rise time, and 1.95 ms fall time. It has also the highest contrast ratio. Moreover, it has a maximum measured transmission that is higher than those for PCH5 and 7CB by about 17 % and 8%, respectively, at a field strength of 2V/mm. Findings: The obtained results indicate that the electrooptic properties of PCH5 was improved when mixed with a proper ratio of 7CB, of lower cost, more stablity , and higher potential for photonic applications. Unique Contriburibution to Theory, Practice and Policy: This expermental study shows that simply by mixing two relatively low cost NLCs materials, one of high thermal stability and low electro-optic properties with other one of low thermal stability and better electro-optic properties; this would improve the stability, response, and transmition of the binary mixture. If the a suitable driving method is applied, without doping with other orgnic or inorganic matrial.

The content optimization of supplementary cementitious materials in coral sand-seawater cement mortar: A focus on mechanical properties and transportation costs

This study examines how supplementary cementitious materials (SCMs) such as fly ash (FA), blast furnace slag (BFS), and metakaolin (MK) affect the mechanical properties and transportation costs of coral sand-seawater cement mortar (CSSC). The Dinger-Funk equation was used to obtain the most densely packed design and preparation of coral sand and cementitious materials. The mechanical properties of CSSC were assessed utilizing the RMT testing apparatus. A thorough examination of the mechanical properties and transportation costs of CSSC was undertaken using the principle of value engineering and the effectiveness coefficient approach. Research results show that BFS10 has outstanding mechanical qualities in the binary cementitious system. Within the ternary cementitious system, the mechanical qualities typically exceed those of the binary system, with FA15BFS15 demonstrating the highest performance. The best appropriate mix ratio is FA15BFS15, as determined by a thorough examination and cost-benefit analysis. This ratio offers temporal sensitivity and maximized transit capacity. The SVR model is highly proficient in forecasting the compressive strength of CSSC, showcasing accurate prediction and data interpretation abilities. The research findings provide practical evidence for optimizing the proportion of CSSC in calcium sulfoaluminate cement, considering transportation expenses and algorithm prediction needs.

Additive Water Uptake of the Mixtures of Urban Atmospheric HULIS and Ammonium Sulfate

AbstractThe hygroscopicity of atmospheric aerosols affect the global climate and human health. However, the hygroscopic behavior of mixtures of inorganic salts and organics in atmospheric aerosols have not been well characterized for ambient complex organic mixtures. Here, the hygroscopic growth of humic‐like substances (HULIS), which represent the complexity of organic aerosol compounds, from urban aerosols and their mixtures with ammonium sulfate were investigated with measurements from a hygroscopicity tandem differential mobility analyzer and model analyses. The Zdanovskii–Stokes–Robinson (ZSR) relationship, which assumes that the water uptake of each component is additive, was examined for the mixtures. The dependence of the hygroscopicity parameters (κ) of the mixtures on the volume fraction of HULIS is generally represented by the ZSR relationship with the deviations of κ on average of 16% (4%–27% in different mixing ratios), and 0.03 (0.02–0.04) on absolute basis. An assumption of asphericity for the dry particles reduced the deviations (14%). Approximations for the surface tension depression by surfactants and surface‐bulk partitioning were predicted to account for the deviations to a small extent. Furthermore, a thermodynamic model for simplified compound systems showed that the non‐ideality of the solutions potentially explained the deviations from the ZSR relationship. The results of this study support the use of the ZSR relationship for organic‒inorganic mixtures as a practical approximation in atmospheric models, provide a guide for the uncertainty associated with this approximation, and suggest directions for future studies.

Study of Characteristics and Heavy Metals Migration During Co-Combustion of Coal and Sludge

ABSTRACT Sludge is a complex mixture involving toxic substances, such as pathogenic microorganisms and heavy metals. Without effective treatment, sludge will pose a serious threat to the ecosystem and human beings. Feeding sludge into combustion boilers as auxiliary fuel and incinerating it as a low quality fuel together with coal high calorific value fuel can reduce the consumption of coal and realize the resourceful use of sludge. It can not only reduce the construction and operation costs of sludge disposal, but also realize the social and ecological benefits of coal-fired power plants. The combustion characteristics and the migration of heavy metals during the co-combustion of coal and industrial sludge were investigated in the paper. The experiments were performed at temperatures ranging from 20°C to 800°C at the constant heating rate of 15°C/min. It was found that the data of combustion index decrease with the increasing mixing ratio. The mixed proportion should not exceed 10%. In the ecological risk assessment of heavy metals, the risk index value of residues gradually increased with the increasing mixing ratio. To keep the residues at a low risk level, the mixing ratio should not exceed 5%. The results of FactSage simulation illustrated that the contents of PbCl2 (g) and ZnCl2 (g) increased with the increase of industrial sludge addition, showing that the combination effect of Cl with heavy metals was stronger than that of heavy metals captured by minerals.

Evaluation of precipitated CaCO3 produced from locally available limestone as a reinforcement filler for PVC pipe.

The current experimental work aimed at developing PCC through two major process steps: dissolution and precipitation, using raw materials domestically available as SL, which are intensively used in construction inputs. The pH level was the decisive parameter used to determine the time required to complete the dissolution and carbonation processes during precipitation. The optimal pH levels were found to be 13 for dissolution and 7.1 for precipitation, respectively. The produced PCC was characterized based on chemical analysis, crystallinity, and morphology, showing an increment of CaCO3 content exceeding 99%, sharper crystal peaks, and predominantly calcite PCC. The compatibility of the PCC was assessed by incorporating 25%, 50%, 75%, and 100% of PCC with commercial filler, followed by selected mechanical tests, such as stress at yield, density, and elongation at break. The results indicated that mixing ratios of 25%, 50%, and 75% of PCC with the commercial filler met the standards, with stress at a yield above 45MPa and density within the range of 1.35 to 1.46g/cm3. However, complete substitution slightly lowered these properties. Nevertheless, the elongation at break was acceptable at all treatment levels.

A method for generating quantitative vapor-phase infrared spectra of solids: results for phenol, camphor, menthol, syringol, dicyclopentadiene and naphthalene

A method is presented to generate quantitative vapor-phase infrared spectra from substances that naturally occur as solids with moderate volatility. The solid is gravimetrically dissolved into a solvent that has few infrared spectral features, typically CS2 and CCl4 separately. The solution is flowed at a constant rate from a linearly pumped syringe into a metered stream of nitrogen carrier gas regulated by a mass flow controller. The analyte/solvent mix is flash vaporized by volatilizing the solution across a heated stainless-steel surface as it emanates from the syringe tip. The N2 gas-solution mixture is flowed into a long-path White cell thermostatted at a desired temperature, the long optical path compensating for the modest analyte mixing ratio. A composite spectrum is generated from typically ten or more 760-Torr pressure-broadened spectra over the 600 to 6500 cm−1 spectral range at 0.1 cm−1 spectral resolution. The solid analytes reported here using this novel technique include dicyclopentadiene, menthol, syringol, phenol, camphor, and naphthalene.

Study on Slump and Compressive Strength of Gangue Based on Aggregate Size Gradation

In order to solve the ecological environment pollution caused by a large amount of coal gangue accumulation and the problems of poor conveying performance and low support strength of paste filling materials. Based on the standard slump test and uniaxial compressive strength test, the slump and compressive strength (post-coagulation) of gangue paste under different aggregate size aggregations were obtained through orthogonal experiments in this study. The results show that the slump of the gangue filling paste with four types of aggregate size gradations is negatively correlated with the mass fraction, and the slump of the filling paste with a coarser aggregate content is more obviously affected by the mass fraction The increase of fine aggregate content has a significant impact on the compressive strength of the filling paste, which shows a trend of first increasing and then decreasing. When the mixing ratio of coarse aggregate and fine aggregate is 5:5, the compressive strength of the paste reaches the best. In addition, different proportions of aggregate mixing cause the filling paste to form different skeleton structures, including the skeleton void structure at 7:3 or 6:4, the skeleton dense structure at 5:5, and the skeleton suspension structure at 4:6, which are decisive for the final performance of the paste. By analyzing the experimental results of the compressive strength and slump of the gangue filling paste, it was found that the relationship between the compressive strength and slump of the gangue filling paste is a power index function. Through data fitting, it was found that the regression coefficient of the fitting function is no less than 0.97, and the fitting effect is good for evaluating the strength of the filling paste under the aggregate size grading.

Formation of two-dimensional mixed monolayers of integrated-cellulose nanofibers and starch nanoparticles using cellulose acetate and soluble starch

In this study, mixed monolayers comprising starch and cellulose nanofibers are prepared on the water surface and effectively controlled their surface morphologies. Through the spreading of cellulose acetate on the water surface, we achieve the preparation of integrated films with the spontaneous formation of nanocellulose. It is confirmed that starch, which is insoluble in the spreading solvent, is solubilized through a soluble treatment and spreads into a monolayer on the water surface. Upon mixing the nanocellulose integrated layer and starch particle layer, the morphology changes based on the mixed ratio of these components. In the monolayer film of a 1:1 mixture of cellulose acetate and soluble starch, the morphology predominantly consists of fibers, with particulate aggregates incorporated here and there. Furthermore, when the ratio changes to 1:5, the mixed monolayer transforms into a single particle layer, while the mixed monolayer evolves into a fibrous integrated film at a ratio of 5:1. Meanwhile, from the evaluation of the surface pressure-area isotherms, it is predicted that both components constitute an ideal mesoscopic miscible system. In addition, in the subphase temperature dependence of the cellulose acetate:soluble starch = 1:1 mixed monolayer, fibers are promoted under low-temperature conditions, and substantial domains are formed under high-temperature conditions. Notably, the mixed film remains amorphous at all ratios and exhibits low surface free energy, simultaneously suggesting hydrophobic and oil-repellent properties.