This study investigates the impact of Mg(OH)2 on the in-situ formation of fibre-like aragonite and the mechanical properties of the cement mortar by accelerated carbonation. The results showed that ...the addition of Mg(OH)2 showed a weak effect on the compressive strength of carbonated samples, but it significantly improved the flexural strength of the carbonated samples. The flexural strength of carbonated sample increased with the addition of Mg(OH)2 content and the carbonated sample with 10% Mg(OH)2 showed approximately twice times than that of the hydrated sample at 28 d. The FTIR and XRD analysis also confirmed that aragonite became the dominate CaCO3 polymorph instead of calcite in carbonated sample with beyond 5% Mg(OH)2 content. The in-situ formed fiber/needle-like aragonite increased the total porosity of carbonated sample when adding Mg(OH)2 compared to the formed calcite in control sample due to the lower carbonation degree, while it refined the pore sizes of carbonated samples. Rhombohedral/cubic calcite and small amounts of long rod-like aragonite were present in the control sample. However, the dominant CaCO3 polymorph of aragonite with a length of 10–20 μm and an ammeter of 1–2 μm were generated in the samples incorporation of Mg(OH)2 and the length/diameter ratio of aragonite increased with the increased Mg(OH)2 dosages. This paper confirmed that reinforced cement composites can be prepared by controlled in-situ formation of fiber-like aragonite under carbonation curing and that an appreciable amount of CO2 can be sequestered.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
During the working process of the falling film evaporator, the airflow generated by evaporation process affects the falling film flow process. A three-dimensional model consisting of two horizontal ...tubes was conducted, which only considered the flow of one liquid column unit. The effect of cross-airflow on the liquid film thickness distribution of tube 1 and tube 2 in the jet mode was studied. The gas is air, the liquid is pure water, and the flow of gas and liquid begins simultaneously. The fluctuation and thickness distribution of the liquid film were analyzed. The research results indicate that liquid film fluctuation occur at the moment when the fluid falls from the first tube to the second tube, and continue to exist thereafter. When the airflow is applied, at l*=0.5, for the tube 1, the liquid film thickness from θ=45° to 90° areas is relatively flat; At l*=1, for the tube 2, the smallest liquid film thickness is located near θ=90° and 270°. The airflow has a certain inhibitory effect on the liquid film waviness on the windward side. The main reason why the liquid film thickness on the leeward side is greater than that on the windward side is due to the offset of the liquid column. The stability of the liquid column, which means that the liquid column does not offset, can ensure the stability of the falling film flow process.
•The shape of liquid film spreading affects the distribution of liquid film thickness.•The fluctuation of the liquid film affects the generation and variation of the liquid column.•The cross-airflow has a certain inhibitory effect on the fluctuation of the liquid film.•The cross-airflow changed the position of the minimum liquid film thickness.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
•FeCoS2/Co4S3/N-doped graphene foam composite was prepared via facile hydrothermal synthesis and chemical vapor deposition process.•The catalyst exhibited remarkable catalytic performance with ...overpotentials of 276 mV for OER and 172 mV for HER at 10 mA·cm−2.•The high catalytic performance was attributed to the Co4S3 and FeCoS2 nanoparticles in-situ grown and evenly distributed on the 3D NGF substrate.•The FeOOH/CoOOH species in situ formed on the surface of FeCoS2/Co4S3/NGF catalyst was the actual catalytic active substance towards OER.
Transition metal sulfide is a kind of electrocatalyst with appropriate cost, high efficiency, and stability. However, introducing additional metal atoms into transition metal complexes to form ternary compounds can more effectively optimize the electronic structure and improve its catalytic performance. In this work, FeCoS2/Co4S3 nanoparticles were groundbreakingly synthesized and loaded on nitrogen-doped graphene foam (NGF) with a 3D network structure by facile hydrothermal synthesis and simple chemical vapor deposition (CVD) process. The transition metal sulfide nanoparticles were uniformly distributed on the surface of NGF substrates. The transition metal sulfide nanostructures can provide a larger surface area, enhance the interaction with the medium, and improve the electrocatalytic performance. The synthesized FeCoS2/Co4S3/NGF catalyst exhibits enhanced HER and OER catalytic performance in 1 M KOH, with overpotentials of 172 mV for the HER and 276 mV for the OER at a current density of 10 mA·cm−2. The performance of the FeCoS2/Co4S3/NGF hybrid catalyst could match the best Fe-Co-S bifunctional electrocatalysts reported in the literature. Strong evidence supports that the FeOOH/CoOOH species in situ formed on the surface of FeCoS2/Co4S3/NGF catalyst was the actual catalytic active substance towards OER. In addition, the Tafel slope, TOF, EIS, and stability test results collaboratively support that Fe-Co-S/NGF shows great potential to be used as a bifunctional electrocatalyst for large-scale overall water electrolysis.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
This paper reports a case study on cleaner production of digital control manufactured sand (DMS) and ecological utilization of recycled SP (stone powder) in Hechi-Baise Expressway Project. The novel ...production system can not only produce high-quality manufactured sand, but also recycle waste stone powder and reduce environmental pollution. Compared with common manufactured sand, the digital control manufactured sand has more reasonable gradation, modified particle shape and regulable stone powder content, which will significantly simplify the ecological application of DMS. The performance of fine aggregate type and stone powder content under several engineering mix proportions is evaluated. The results show that compared with manufactured sand (MS) concrete, the working performance of concrete with DMS is increased by 16.19% on average, and the strength is increased by 7.1% on average, and it has excellent resistance to chloride ion penetration., The application of DMS also reduce the cement and supplementary cementitious materials content of concrete. Recycled SP is comprehensively used in the digital control cleaner production of manufactured sand. The zero discharge of solid waste i.e., waste stone, rubble, dust, and slurry is realized, therefore remarkable economic and ecological benefits are achieved.
•The digital control cleaner production realizes the recovery of stone powder.•Digital control manufactured sand has better gradation and particle shape compared with common manufacture sand.•The addition of DMS and recycled SP improves the properties of concrete.•The application of DMS and recycled SP in expressway engineering has achieved high economic and environmental.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Since the outbreak of COVID-19, a variety of vaccine platforms have been developed. Amongst these, inactivated vaccines have been authorized for emergency use or conditional marketing in many ...countries. To further enhance the protective immune responses in populations that have completed vaccination regimen, we investigated the immunogenic characteristics of different vaccine platforms and tried homologous or heterologous boost strategy post two doses of inactivated vaccines in a mouse model. Our results showed that the humoral and cellular immune responses induced by different vaccines when administered individually differ significantly. In particular, inactivated vaccines showed relatively lower level of neutralizing antibody and T cell responses, but a higher IgG2a/IgG1 ratio compared with other vaccines. Boosting with either recombinant subunit, adenovirus vectored or mRNA vaccine after two-doses of inactivated vaccine further improved both neutralizing antibody and Spike-specific Th1-type T cell responses compared to boosting with a third dose of inactivated vaccine. Our results provide new ideas for prophylactic inoculation strategy of SARS-CoV-2 vaccines.
Abstract High-quality diets have been increasingly acknowledged as a promising candidate to counter the growing prevalence of mental health disorders. This study aims to investigate the prospective ...associations of adhering to the EAT-Lancet reference diet with incident depression, anxiety and their co-occurrence in 180,446 UK Biobank participants. Degrees of adherence to the EAT-Lancet diet were translated into three different diet scores. Over 11.62 years of follow-up, participants in the highest adherence group of the Knuppel EAT-Lancet index showed lower risks of depression (hazard ratio: 0.806, 95% CI: 0.730–0.890), anxiety (0.818, 0.751–0.892) and their co-occurrence (0.756, 0.624–0.914), compared to the lowest adherence group. The corresponding hazard ratios (95% CIs) were 0.711 (0.627–0.806), 0.765 (0.687–0.852) and 0.659 (0.516–0.841) for the Stubbendorff EAT-Lancet index, and 0.844 (0.768–0.928), 0.825 (0.759–0.896) and 0.818 (0.682–0.981) for the Kesse-Guyot EAT-Lancet diet index. Our findings suggest that higher adherence to the EAT-Lancet diet is associated with lower risks of incident depression, anxiety and their co-occurrence.
A reference standard is needed for quality control of protein subunit SARS-CoV-2 vaccines to meet urgent domestic needs. The Chinese National Institutes for Food and Drug Control (NIFDC) launched a ...project to establish the first reference material for the protein subunit SARS-CoV-2 vaccine to be used for calibration of antigen testing. The potency and stability of the national candidate standard (CS) were determined by collaborative calibration, and accelerated and freeze–thaw degradation studies. Moreover, a suitability study of the CS was performed. Eight laboratories in mainland China were asked to detect antigen content of CS using a common validated enzyme-linked immunosorbent assay (ELISA) kit established by NIFDC and in-house kits in the collaborative study. Six laboratories returned valid results, which established that the antigen content of the CS was 876,938 YU/mL, with good agreement across laboratories. In the suitability study, the CS exhibited excellent parallelism and a linear relationship with four samples produced by different expression systems and target proteins. In addition, good stability in the accelerated and freeze–thaw degradation study was observed. In conclusion, the CS was approved by the Biological Product Reference Standards Sub-Committee of the National Drug Reference Standards Committee as the first Chinese national standard for determining antigen content of protein subunit SARS-CoV-2 vaccines, with an assigned antigen content of 877,000 U/mL (Lot. 300050–202101). This standard will contribute to a standardized assessment of protein subunit SARS-CoV-2 vaccine in China and may provide experience for developing reference materials for antigen content detection of SARS-CoV-2 vaccine in other countries.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
•C40 Fair-faced self-compacting concrete (FFSCC) was prepared and applied successfully in second lining of tunnel.•The effects of APT values on workability, strength and surface porosity of FFSCC ...were analyzed in detail.•The fitting relationships between the meso-structure, mix design and the properties of FFSCC were obtained.
Fair-faced concrete (FFC) with excellent decorative effect is a kind of concrete which can be directly used as external facade, whereas the low workability and complex molding process of the ordinary FFC restricts its broad application. In this study, the C40 self-compacting FFC (named as fair-faced self-compacting concrete or FFSCC for short) was prepared. With the reference of average paste thickness (APT) theory, the effects of coarse aggregate gradation and content, sand content and mineral admixture content on workability, compressive strength and decoration effect of FFSCC were quantitatively analyzed to obtain an optimal mix proportion of FFSCC. The results indicated that the increased proportions of 5–10 mm aggregates or higher aggregate content would lead to the lower APTs, which resulted in lower workability, lower surface porosity, and higher strength. Fitting results between APT and several properties presented that the fluidity, flow velocity and compressive strength possessed the linear relationships with APT values. While the passing capacity, segregation ratio and surface porosity possessed the quadratic polynomial relationships with APT values. Furthermore, atomic force microscopy (AFM) was applied to observe the surface texture of FFSCC. Results showed that its surface roughness (RMS) was 3.7 nm, which was smoother than the polished cement paste. Finally, the optimal FFSCC was successfully applied in second lining of Nan Kunshan tunnel.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Biological processes, such as bone defects healing are precisely controlled in both time and space. This spatiotemporal characteristic inspires novel therapeutic strategies. The sustained-release ...systems including hydrogels are commonly utilized in the treatment of bone defect; however, traditional hydrogels often release drugs at a consistent rate, lacking temporal precision. In this study, a hybrid hydrogel has been developed by using sodium alginate, sucrose acetate isobutyrate, and electrospray microspheres as the base materials, and designed with ultrasound response, and on-demand release properties. Sucrose acetate isobutyrate was added to the hybrid hydrogel to prevent burst release. The network structure of the hybrid hydrogel is formed by the interconnection of Ca2+ with the carboxyl groups of sodium alginate. Notably, when the hybrid hydrogel is exposed to ultrasound, the ionic bond can be broken to promote drug release; when ultrasound is turned off, the release returned to a low-release state. This hybrid hydrogel reveals not only injectability, degradability, and good mechanical properties but also shows multiple responses to ultrasound. And it has good biocompatibility and promotes osteogenesis efficiency in vivo. Thus, this hybrid hydrogel provides a promising therapeutic strategy for the treatment of bone defects.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Dissipative Kerr nonlinear cavities attract intense interest due to their rich dynamics and capability to generate broadband, low-noise, mode-locked optical frequency combs for applications in ...optical communications, dual-comb spectroscopy, photonic lidar, etc. Different from the Kerr effect, which is an electronic response, stimulated Raman scattering (SRS) is a delayed response to molecular vibrations in materials. In microcavities, when driven in an anomalous group velocity dispersion (GVD) regime, SRS typically leads to a self-frequency shift of solitons and generation of breather solitons, which have been verified both theoretically and experimentally. However, when driven in a normal GVD regime, recent theoretical work predicts that SRS can cause the locking of switching waves (SWs) and thus support bright moving localized structure (LS), which we term as SRS enabled localized structure (SRS-LS). Limited by the design of suitable experimental parameters, experimental observation of this SRS-LS is not achieved yet. Here, we provide numerical investigation and, to our knowledge, the first experimental observation of the SRS-LS in a fiber Fabry–Perot (FP) resonator with ultra-low normal GVD. Such SRS-LS exhibits localized temporal features with strong oscillations at ∼13THz local frequency on the top of a flat-top pulse. The corresponding spectrum is a low-noise and broadband Kerr comb with a typical platicon-like spectrum in the center and two Raman Stokes and anti-Stokes peaks located near ±13THz away from the center. With such an SRS enabled broadband Kerr comb, we have achieved an SRS-LS spectrum with a repetition rate of ∼3.68GHz and a −30dB spectral width of 255 nm. The corresponding comb tooth count is >8500, covering the S + C + L telecommunication bands. Moreover, the formation process of such SRS-LS is also revealed, and it is found that the GVD plays a key role in its generation. Our work will help to advance the study of the dynamics of optical frequency combs under the influence of SRS, as well as provide a broadband coherent mode-locked optical source for wide applications.
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