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Background: Remimazolam is a benzodiazepine sedative that is indicated for induction and maintenance during general anaesthesia. Remimazolam is also used for sedation in outpatient surgery; however, most reports have focused on nonelderly patients, whereas only a few studies have reported the use of remimazolam for elderly patients when receiving regional nerve block anaesthesia. Aim: The aim of this study was to evaluate the effects of different doses of remimazolam in elderly patients when specifically related to regional nerve block anaesthesia. Methods: This study was conducted at a university hospital between February 2022 and March 2023. We included 80 patients aged 65 years or older under regional nerve block anaesthesia. After the effects of anaesthesia were determined, patients were intravenously administered different doses of the test drug, i.e. 4, 4.5, 5, 5.5, or 6 mg, which were named the R1, R2, R3, R4, and R5 groups, respectively. The primary outcome was the loss of consciousness time. The secondary outcomes included the maintenance time and the number of assisted ventilators needed. The exceptional response of patients in terms of loss of consciousness maintenance time, the mean arterial pressure (MAP), heart rate (HR), respiratory rate (RR), SpO2, and modified observers assessment of alertness/sedation (MOAA/S) scores were recorded at baseline (T0), 3 min after the injection of the test drug (T1), 6 min after the injection of the test drug (T2), 9 min after the injection of the test drug (T3), 12 min after the injection of the test drug (T4), 15 min after the injection of the test drug (T5), 18 min after the injection of the test drug (T6), 21 min after the injection of the test drug (T7), and 24 min after the injection of the test drug (T8). Results: We included 80 patients according to the inclusion and exclusion criteria, with 16 patients in each group. There were no significant differences in sex, age, and BMI amongst the 5 groups. The loss of consciousness time was significantly greater in the R2 group than in the R3, R4, and R5 groups (p< 0.001), and the loss of consciousness maintenance time was significantly greater in the R5 group than in the R3 group (p< 0.05). The MAP was significantly lower in the R2 and R5 groups than in the R1 group at T4 (p= 0.004) and significantly lower in the R5 group than in the R1 group at T5 (p= 0.007). The HR was significantly lower in the R5 group than in the R3 group at T3 (p= 0.004) and T4 (p= 0.007). The RR was significantly lower in the R5 group than in the R4 group at T4 (p= 0.049) and significantly greater in the R4 group than in the R2 group at T5 (p= 0.024) and T6 (p= 0.020). The RR was significantly lower in the R5 group than in the R1, R3 and R4 groups at T7 (p= 0.001). The RR was significantly greater in the R1 group than in the R2 and R5 groups at T8 (p= 0.001). The RR was significantly greater in the R4 group than in the R2 group at T8 (p= 0.001). SpO2was significantly lower in the R3 group than in the R1 group at T3 (p= 0.003) and significantly lower in the R3 group than in the R1 and R5 groups at T4 (p= 0.002), T5 (p= 0.001), T6 (p= 0.000), and T7 (p= 0.000). The MOAA/S scores were significantly lower in the R4 and R5 groups than in the R1 and R2 groups at T1 (p= 0.000), significantly lower in the R5 group than in the R1 and R3 groups at T2 (p= 0.004), and significantly lower in the R5 group than in the R1 group at T3 (p= 0.036). Conclusion: The results indicated that doses of 5–5.5 mg remimazolam are more suitable for sedation in elderly patients, and the loss of consciousness time and depth of sedation differed according to the remimazolam dosage. Doses of 5–5.5 mg remimazolam were associated with adequate levels of sedation in elderly patients and with a decreased risk of complications, whilst haemodynamic fluctuations occurred approximately 12–15 min after the administration of remimazolam.

The purpose of this paper is to overcome the problems of high communication failure probability, high energy cost, low global connectivity and poor network robustness, a dynamic key distribution method based on exponential algorithm is proposed. In this method, the collusion characteristics of newly added nodes and revoked nodes in wireless sensor networks are used to establish a wireless sensor security model. The exponential algorithm is used to initialise, broadcast, self repair session key and mutual session key It can help repair, add nodes and cancel nodes to realise dynamic key distribution. The experimental results show that when the number of dynamic key nodes is 600, the probability of communication failure is 47%; when the number of hops is 10, the energy cost is only 1.64 mJ, and the network robustness is high. It reduces the pressure of wireless sensor network and plays a positive role in the root cause location of massive alarm information fault.

Worldwide, wheat (Triticum aestivumL.) serves about 20% of the human calorie needs and 40% of protein needs. Hence, it is imperative to pay attention to its nutritional quality. About 74–78% of a wheat kernel consists of carbohydrates, where starch is the predominant type. The soluble amylose-amylopectin ratio greatly affects the quality of different products. Moreover, the water-soluble carbohydrates stored in the culm contribute significantly to the plant's drought tolerance during the dry spells of the growth cycle. The wheat protein content typically ranges between 8% and 16%, and its content and composition primarily determine the wheat's end-use quality. Wheat grains are rich in trace elements, such as calcium, zinc, iron, and selenium. These elements are essential for human growth and development. In addition, wheat kernels accumulate various pigments that give them characteristic colors. Based on recent studies, these colored grains are recommended to consumers due to their health benefits. However, breeding for these nutritional traits is remarkably challenging due to their complex genetics and environmental influence. In this review, we summarized the genes/QTLs mapped for wheat starch, protein, and micronutrient (e.g., calcium, iron, zinc, and selenium) content, and pigments (carotenoids and anthocyanins), with a hope that this review will serve as a resource for wheat breeders and provide up-to-date information on the genetic of wheat nutrient-related traits.

Drought and salt stress are important factors that affect plant growth and development and cause crop yield reductions worldwide. Phospholipase C is a class of enzymes that can hydrolyze phospholipids, and it has been shown to play an important role in plant growth regulation and stress response. We used rice as a model to investigate the function of the wheat TaPI-PLC1-2Bgene in salt and drought tolerance. For this purpose, we heterologously expressed the TaPI-PLC1-2Bgene in rice and studied the transcriptional differences in transgenic and wide-type rice plants in the presence and absence of drought and salt stress. Our results showed that 2130 and 1759 genes expressed differentially in the TaPI-PLC1-2Boverexpression rice line under salt and drought stress, respectively. Gene ontology enrichment results showed that differentially expressed genes (DEGs) were significantly enriched in cellular process, metabolic process, stimulus-response, cell, organelle, catalytic activity, and other functional processes under salt and drought stress. In addition, the Kyoto Encyclopedia of Genes and Genomes pathway analysis showed DEG enrichment in plant-pathogen interaction, phosphoinositol, plant hormones, and other signaling pathways under the two stress treatments. Furthermore, the chromosomal localization of salt and drought stress-responsive DEGs showed a clear distribution pattern on specific rice chromosomes. For instance, the greatest number of drought stress-responsive genes mapped to rice chromosomes 1 and 6. The current analysis has built the basis for future explorations to decipher the TaPI-PLC1-2B-mediated plant stress response mechanism in the relatively challenging wheat system.

Cellular senescence, a process that arrests the cell cycle, is a cellular response mechanism for various stresses and is implicated in aging and various age-related diseases. However, the understanding of senescence in living organisms is insufficient, largely due to the scarcity of sensitive tools for the detection of cellular senescence in vivo. Herein, we describe the development of a self-immobilizing near-infrared (NIR) fluorogenic probe that can be activated by senescence-associated β-galactosidase (SA-β-Gal), the most widely used senescence marker. The NIR signal is turned on only in the presence of SA-β-Gal, and the fluorescence signal is retained to the site of activation viain situlabeling, significantly enhancing the sensitivity of the probe. We demonstrate its efficient noninvasive imaging of senescence in mice xenograft models.

ABSTRACTFull-waveform inversion (FWI) is one of the most promising inversion methods in geophysics due to its theoretical completeness and high resolution. However, the inversion ability of FWI strongly relies on the accuracy of the initial model and the quality of the low-frequency data. For FWI, it is important to accurately recover low and middle wavenumber components (the background model). In order to invert for the background model, we use a new strategy to compose the plane-wave using reference source points. With the new algorithm, more plane-waves can be composed for a single ray parameter to obtain the background model by plane-wave multi-scale full-waveform inversion (PMFWI) method. By controlling the ray parameter in this method, the low to middle wavenumber components can be recovered in sequence. Composing several plane-waves for a single ray parameter enables the illumination to be significantly improved, even for incomplete data. As only a small number of plane-waves are needed in this method, the computation burden greatly decreases. Analysis of numerical tests also verifies that the proposed inversion strategy is robust, to a certain extent, for high-frequency or noisy data. Application of this method on a modified portion of a SigsBee 2A model illustrates that, combined with conventional FWI, PMFWI has suitable model accuracy, even for coarse initial model data and high-frequency data.

Long non-coding RNA H19 (H19) plays an important role by regulating protein expression in different tissues and organs of the body. However, whether H19 induces hypoxia/reoxygenation (h/R) injury via increase of autophagy in the hepatoma carcinoma cells is unknown. H19 was expressed in the hepatoma carcinoma cells (Hep G2 and HCCLM3 cells) and its expression was most in 8 h/24R. The knockdown of H19 and 3-MA (an autophagy inhibitor) protected against h/R-induced apoptosis, cell damage, the expression of cleaved caspase-3 and cleaved caspase-9, the release of cytochrome c(Cyt c). The knockdown of H19 and 3-MA also decreased the autophagic vesicles (AVs) and the expression of Beclin-1 and the ration of LC3-II/LC3-I, and increased cell viability, the expression of Bcl-2 and P62 and the phosphorylation of PI3K, Akt and mTOR. In addition, chloroquine (CQ, an inhibitor of autophagy flux) markedly decreased formation of autophagy flux (the ration of LC3-II/LC3-I). The results of the knockdown of H19 group were similar to those of the 3-MA (or CQ) group. Rapamycin (a mTOR inhibitor, an autophagy activator) further down-regulated h/R-induced decrease of the phosphorylated PI3K, Akt and mTOR. The knockdown of H19 cancelled the effect of rapamycin. The overexpression of H19 further expanded h/R-induced increase of the ration of LC3-II/LC3-I and decrease of the phosphorylated PI3K, Akt and mTOR. Our results suggest that the long non-coding RNA H19 induces h/R injury by up-regulation of autophagy via activation of PI3K–Akt–mTOR pathway in the hepatoma carcinoma cells.

Climate change assessment is central for low-carbon management practice. This paper investigates China’s National Climate Change Assessment Reports of 2007, 2011, and 2015. These three reports are compared with other climate change assessment reports by data mining. The necessity of national climate change assessment is analyzed with the requirements at home and abroad. The latest progress surrounding climate change impacts, adaptation, and mitigation is outlined with the increasing temperature rise in China and the urgency of climate change commitments. The achievements in climate change assessment indicate the increasing climate change vulnerability on sectors and regions in China and the strategies and priorities for low-carbon actions. Distinct gaps and differences are identified in the coverage of industry, regions, and vulnerability assessment between our assessments and other evaluation reports. These gaps and differences demonstrate the importance and future improvements of China’s national climate change assessment in international climate governance. The outlook for China’s fourth assessment report is proposed.

Selection of parameters (e.g., the probability of choosing an X-basis or Z-basis, the intensity of signal state and decoy state, etc.) and system calibrating are more challenging when the number of users of a measurement-device-independent quantum key distribution (MDI-QKD) network increases. At present, optimization algorithms are usually employed when searching for the best parameters. This method can find the optimized parameters accurately, but it may take a lot of time and hardware resources. This is a big problem in a large-scale MDI-QKD network. Here, we present, to the best of our knowledge, a new method, using a back propagation artificial neural network (BPNN) to predict, rather than search, the optimized parameters. Compared to optimization algorithms, our BPNN is faster and more lightweight, and it can save system resources. Another big problem brought by large-scale MDI-QKD networks is system recalibration. BPNN can support this work in real time, and it only needs to use some discarded data generated from the communication process, rather than adding additional devices or scanning the system.

Covalent organic frameworks (COFs) show promising prospect as the photocatalysts with advantages of exceptional light adsorption capabilities, large specific surface area, and adjustable band structure. However, COFs usually suffer from severe recombination of photogenerated carriers. Therefore, there is an urgent need to design effective COF-based heterostructures to enhance the separation of carriers. In this work, a porphyrin-based COF with electron donor-acceptor structure is synthesized viacondensation polymerization by using 5, 10, 15, 20-tetrakis (4-aminophenyl) porphyrin (TAPPP) and N, N, N, N-tetra(4-aldehydephenyl)-1, 4-phenylenediamine as the electron donor and acceptor, respectively. Subsequently, ZnIn2S4(ZIS) are successfully in-situgrown on the surface of porphyrin-based COF, forming a novel core-shell structure. The in-situ synthesized ZIS with positive charges can be easily adsorbed on the negatively charged sites of the COF’s surface via the electrostatic interaction. This organic/inorganic hybrid COF-ZIS heterostructure exhibits a superior photocatalytic hydrogen evolution (PHE) rate of 695 μmol g−1h−1, approximately three times higher than that of ZIS. The construction of COF-ZIS heterostructure played an important role in enhancing the separation and transport of photogenerated carriers, which provided more electrons at the surface of ZIS to take part in proton reduction. Electron paramagnetic resonance spectra confirm the charge carriers transfer mode in the COF-ZIS heterostructure via an S-scheme mechanism. Moreover, upon loading Pt as the cocatalyst, the heterostructure achieves an effective PHE rate of 2711 μmol g−1h−1along with an exceptional stability. Additionally, the COF-ZIS heterostructure reaches up to 2.45% of apparent quantum efficiency at 400nm. Notably, the average lifetime of the COF-ZIS heterostructure increases by 43.2% and 98.9% compared to that of ZIS and COF individually, as observed through single-particle fluorescence spectroscopy. This work gives valuable inspiration into the building of donor-acceptor COF-based S-scheme heterostructures to achieve highly effective green energy conversion by aligning band structures.

CO2geological sequestration in coal seams is an effective method for reducing CO2emissions and enhancing coal-bed methane extraction. In this context, the coal–fluid interfacial tension (γcoal–fluid) is a critical parameter that influences the CO2injection, fluid distribution, CO2storage capacity, and containment safety. Especially, the γcoal–fluidcannot be directly measured, and the influencing factors for γcoal–fluid(including γcoal−CO2and γcoal–waterin the coal–water–CO2system) were not reported before. In this study, we calculated the γcoal–fluidof different rank coals under different pressures (3–8 MPa) and temperatures (40–70 °C) by using the combination of Young’s equation and Neumann’s equation. The results show that the γcoal−CO2of all coal samples decreases with increasing pressure and coal rank, while it increases with increasing temperature. The γcoal–waterslightly decreases with increasing temperature. Furthermore, we conducted a comprehensive investigation into the influence mechanism underlying these factors on γcoal–fluidand quantitatively established the γcoal−CO2assessment model. Based on this, we also proposed a methodology for determination of the threshold pore size of caprock (TPSC) and evaluation of sealing security. The calculated TPSC decreases with the increase of burial, and a more water-wetting caprock corresponds to a lower TPSC. This study contributes to a deeper understanding of the wetting phenomenon in the coal–water–CO2system and provides insight into monitoring the safety of CO2sequestration in coal reservoirs.

To investigate the effects of fertilization methods and types on wheat rhizosphere microorganisms, macroelement (N, K) and microelement (Zn) fertilizers were applied on wheat by foliar spraying (FS) and root irrigation (RI) methods in a field experiment. The results indicated that fertilization methods and types can have significant impacts on the diversity and structure of rhizospheric microorganisms in wheat. The application method produced more significant effects than the fertilizer type. RI-N played a more important role in improving the wheat yield and quality and affected the changes in some nitrogen-fixing bacterial communities. Finally, eight strains of bacteria belonging to Pseudomonas azotoformansand P. cedrinashowed positive effects on the growth of wheat seedlings. Overall, our study provides a better understanding of the dynamics of wheat rhizosphere microbial communities and their relation to fertilization, yield, and quality, showing that plant growth-promoting rhizobacteriawith nitrogen fixing may be a potential approach for more sustainable agriculture production.

Natural gas hydrate is a promising clean and efficient energy source, but reformation during mining can impede commercial utilization. The impact of gas flow on hydrate reformation and reservoir seepage characteristics has not been extensively researched despite being a crucial parameter in hydrate mining processes. This study employs a core holder to simulate the formation and dissociation of hydrate in clayey silt sediments from the South China Sea (SCS). Differential gas pressure gradients were manipulated to simulate reformation under varying gas flow conditions, during which the water content and pore distribution were quantified with a low-field nuclear magnetic resonance (NMR) spectrometer. Meanwhile, the gas permeabilities k(Sh) concerning different hydrate saturation (Sh) were measured under constant effective stress. Results indicated that gas flow effectively enhances hydrate reformation, resulting in an increase of the maximum hydrate saturation from 9.44% to 21.15% and an increase of the average reformation rate from 0.15 cm3/h to 0.26 cm3/h with an escalating gas pressure differential from 0 to 1 MPa. Hydrate growth primarily occurs laterally along the gas–water interface under low saturation conditions (ΔSh< 10%), while vertical growth dominates at high hydrate saturations (ΔSh> 10%). Notably, the gas flow encourages hydrates to occupy capillaries with a smaller radius under high saturation conditions.

This paper aims to study the effect of the normal stress on the shear performance of splicing joints for precast ultrahigh-performance concrete (UHPC) segmental bridges (PUSBs), an oblique-shear joint is designed to decompose the vertical force into a normal force and a shear force for the joint. The effect of the number, height and inclination angle of the keys on the bearing capacity of the joint is studied by 19 oblique-shear joints. Then, the bearing capacity and failure modes are analyzed significantly. The results show that the failure modes of the joints are shear failure, compression-shear failure and splitting failure, all showing primarily brittle failure. Moreover, the proportion of shear stress in the specimens increases with the increase of the inclination angle of the joint, and the shear capacity of the specimens decreases. Additionally, the shear capacity of the specimens increases with the increase of the height of the keys. After that, we derive a new formula for calculating the shear capacity utilizing Mohr’s stress circle theory and Mohr-Coulomb failure criterion, i.e., the interfacial frictional coefficient is 0.94 and the shear capacity of keys is 0.06. One may find the present formula shows a high guarantee by comparing with those from references. The formula established in this paper may be used to calculate the shear capacity of splicing joint of precast ultrahigh-performance concrete segmental bridges.

The solubility data of ε-2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane in six binary solvents (n-hexane, n-heptane, n-octane, isooctane, cyclohexane, and methylbenzene mixed with various mole fractions of ethyl acetate) was experimentally studied by the gravimetric method at temperatures ranging from 283.15 to 323.15 K under an atmosphere pressure of 0.1 MPa. The results of these measurements were correlated with the modified Apelblat equation, CNIBS/R-K equation, and Jouyban–Acree model. All three models provide a satisfactory correlation.

Photoinduced charge carrier separation derived by magnetic fields has attracted increasing attention for its ability to wireless regulate powder photocatalysts. In this study, carbon nanotubes (CNT) were used as network conductors to link ZnIn2S4nanosheets. The electron highway in CNT spontaneously enhanced the photoinduced charge carrier transfer between ZnIn2S4nanosheets. The photocatalytic H2evolution rate of the 3 wt % CNT-ZIS composite increased to ∼210 % compared to that of pure ZIS under 300 W xenon lamp illumination. Additionally, in a magnetic field with relative motion, the Lorenz force on photoinduced electrons and holes suppressed their recombination, while the motional electromotive force along CNT accelerated the electron transfer to surface active sites. Therefore, the photocatalytic H2evolution rate further increased to 290 %. The spontaneous and passive photoinduced charge carrier separation in CNT-ZnIn2S4network composites under a magnetic field contributed to enhanced photocatalysis. Moreover, CNT-based network semiconductor composites can be mass-produced at low cost. Magnetic field-enhanced photocatalysis can be universally achieved without limitation caused by intrinsic band structures.

Splicing joints are the weak link of precast ultrahigh-performance concrete (UHPC) segmental bridges (PUSBs). Thus, this paper conducts direct shear tests on eight groups of UHPC keyed joints to investigate the shear performance of the interface of the key. The effects of lateral compressive stress (σn) and the number of keys on the shear performance are also examined. In addition, the load–displacement curves, failure modes, cracking loads, and ultimate loads of the specimens with different parameters are presented. After that, the direct shear capacity of the joints is theoretically analyzed based on the test results and relevant specifications, and a formula for calculating the direct shear capacity is derived. The results show that the failure mode of the UHPC keyed joints is primarily brittle failure. Moreover, the failure mode is the direct shear failure along the interface of the key when the lateral compressive stress is low; however, it is the local crushing of concrete in the key when the lateral compressive stress is high. Additionally, the direct shear capacity of the specimens increases linearly with raising the lateral compressive stress. The direct shear capacity of the double-keyed joints is 17.4–29.3 % higher than that of the single-keyed joints under the same conditions. The values calculated by specifications NF P-18 710 and Eurocode 2 2011 are lower than the experimental ones. The experimental data are evenly distributed on both sides of the curve calculated by specification JSCE 2008 when the lateral compressive stress is low, posing potential hazards in this case. The value predicted by specification AASHTO 2003 is also higher than the experimental value. Finally, we derive a formula for calculating the direct shear performance of the UHPC keyed joints utilizing Mohr’s stress circle theory, and it can be applied to engineering design with high accuracy.

Carbon coated SnS/SnO2heterostructures wrapping on carbon nanofibers (C@SnS/SnO2@CNFs) was demonstrated to have excellent performance as an anode material for Li-ion batteries. C@SnS/SnO2@CNFs electrode delivers high reversible capacity of 826.8 mA h g–1(500th cycle) at the current density of 1.0 A g–1. However, an interesting phenomenon of increasing capacity on cycling can be observed. According to the analysis of the evolution of structure and electrochemical property, C@SnS/SnO2@CNFs is demonstrated to experience the progress of conversion from nanowalls containing polycrystals into amorphous nanosheets with high porosity and larger surface upon cycling. The above lithiation-induced structural optimization provides larger effective surface areas and encourages the conversion reactions, which can promote charge transfer and also enhance the reversibility of the conversion reactions of SnS and SnO2inducing the increasing reversible capacity. The study explains the progress of increasing capacity of C@SnS/SnO2@CNFs and likewise provides a perspective on optimization of the electrochemical performance of electrodes.

Visualization and quantification of important biomolecules like glutathione (GSH) in live cells are highly important. The existing methods are mostly from optical detection and lack of atomic resolution on the activity of GSH. Here, we present a sensitive 19F-NMR method to quantify real-time variations of GSH in live cells in a reversible manner. This NMR method prevents extracellular leakage and irreversible consumption of intracellular GSH during the detection. The high performance of the reactive 19F-probe enables accurate determination of intracellular GSH content at atomic resolution, from which information on GSH variations with respect to the extracellular and intracellular conditions can be inferred. In addition, we demonstrate the applicability of this NMR method to quantify the GSH levels between different live cell lines and to disclose the distinct differences between the intracellular environment and cell lysates. We foresee the application of 19F-NMR to monitor real-time variations of intracellular GSH levels in relation to GSH-involved central cellular processes.

The recruitment of leukocytes to infectious foci depends strongly on the local release of chemoattractant mediators. The human CXC chemokine receptor 3 (CXCR3) is an important node in the chemokine signaling network and is expressed by multiple leukocyte lineages, including T cells and macrophages. The ligands of this receptor originate from an ancestral CXCL11 gene in early vertebrates. Here, we used the optically accessible zebrafish embryo model to explore the function of the CXCR3-CXCL11 axis in macrophage recruitment and show that disruption of this axis increases the resistance to mycobacterial infection. In a mutant of the zebrafish ortholog of CXCR3 (cxcr3.2), macrophage chemotaxis to bacterial infections was attenuated, although migration to infection-independent stimuli was unaffected. Additionally, attenuation of macrophage recruitment to infection could be mimicked by treatment with NBI74330, a high-affinity antagonist of CXCR3. We identified two infection-inducible CXCL11-like chemokines as the functional ligands of Cxcr3.2, showing that the recombinant proteins exerted a Cxcr3.2-dependent chemoattraction when locally administrated in vivo. During infection of zebrafish embryos with Mycobacterium marinum, a well-established model for tuberculosis, we found that Cxcr3.2 deficiency limited the macrophage-mediated dissemination of mycobacteria. Furthermore, the loss of Cxcr3.2 function attenuated the formation of granulomatous lesions, the typical histopathological features of tuberculosis, and led to a reduction in the total bacterial burden. Prevention of mycobacterial dissemination by targeting the CXCR3 pathway, therefore, might represent a host-directed therapeutic strategy for treatment of tuberculosis. The demonstration of a conserved CXCR3-CXCL11 signaling axis in zebrafish extends the translational applicability of this model for studying diseases involving the innate immune system.

With the development of aerospace technology, the temperature resistance of traditional silicone resins fails to satisfy the ever-increasing demand from the stringent application conditions. In this paper, we used diphenyl sulfide (TBSP), diphenyl sulfoxide (SIBSP), and diphenyl sulfone (SODP) to modify the main chain of SiR by hydrolysis-condensation and prepared the quartz fiber reinforced SiR composites. The mechanical properties of QF@SiR composites were measured, and the effects of temperature on the mechanical properties were investigated. Compared with QF/SiR, the ILSS and bending strength of QF/SiR@SODP composites enhanced from 15.58 MPa to 183.59 MPa–25.36 MPa and 338.37 MPa at room temperature. Moreover, at 500 °C, the ILSS and bending strength of QF/SiR@SODP were 11.87 MPa and 114.37 MPa, representing an enhancement of 514% and 315% compared with SiR composite. The structural, heat resistance and composition changes of the composites were determined by SEM, TG and IR, and the failure mechanism of the composites at high temperature was elucidated.

We report carbon isotopic values in total organic carbon (TOC) and pyrogenic carbon (PyC) preserved in two sediment cores from the Ross Sea, Antarctica. The δ13C values of PyC ranged from −10.9‰ to −17.2‰, with distinct differences from the δ13C values of TOC (−24.1‰ to −26.1‰) in the sediments. The radiocarbon ages of PyC were 9,128 and 8,410 years old on average in the two cores but were thousands of years younger than the ages of TOC at the same core depth. These isotopic records provide strong evidence indicating that the PyC was produced from ancient wildfires predominantly in C4vegetation and transported to Antarctica in the atmosphere. We suggest that ancient wildfires in predominantly C4grasslands likely frequently occurred on a large scale and at a high intensity in the Southern Hemisphere during the last deglaciation to mid‐Holocene period of 14,800–4,200 years ago. A large fraction of pyrogenic carbon (PyC) is produced from incomplete combustion of biomass fires on Earth and is widely distributed on land and in the oceans. This study presents the first evidence of both radiocarbon and stable carbon isotopes in the PyC preserved in the slope sediments of the Ross Sea in Antarctica. The results revealed that PyC accounted for a significant fraction (10.0%–28.0%) of the sedimentary total organic carbon (TOC) buried in the sediments, and both the Δ14C and δ13C values of PyC showed distinctive differences compared with those of TOC. The well‐defined δ13C (−10.9‰ to −17.2‰) and Δ14C (−415‰ to −843‰) values of PyC in the sediments revealed that in ancient times, PyC was produced from wildfires of C4vegetation in the Southern Hemisphere and was transported in the atmosphere to Antarctica. The isotopic records of PyC preserved in the Ross Sea sediments provide meaningful evidence for environmental changes. Pyrogenic carbon (PyC) constitutes a significant fraction of total organic carbon (TOC) preserved in sediment of the Ross Sea, AntarcticaDistinctive differences in both radiocarbon and stable carbon isotope values exist between PyC and TOC in the Ross Sea sedimentThe isotopic records indicated that the PyC was produced from ancient wildfires in C4grasslands and transported to Antarctica in atmosphere Pyrogenic carbon (PyC) constitutes a significant fraction of total organic carbon (TOC) preserved in sediment of the Ross Sea, Antarctica Distinctive differences in both radiocarbon and stable carbon isotope values exist between PyC and TOC in the Ross Sea sediment The isotopic records indicated that the PyC was produced from ancient wildfires in C4grasslands and transported to Antarctica in atmosphere

With pumice as the additive agent used in cement composite soil . In order to test the mechanical performance of the composite cement soil, the unconfined compression resistance and triaxial test were done in the lab with different additive quantity (25%,50%), different cement content (8%,12%,16%,20%), The results show that the strength of the composite cement soil are significantly increase with increasing cement content , there is an optimum amount 16%.The pumice powder may evidently improve the mechanical properties of soft soil.

With pumice as the additive agent used in cement composite soil . In order to test the mechanical performance of the composite cement soil, the unconfined compression resistance and freezing and thawing cycle test were done in the lab with different additive quantity(2%,4%,6%,8%,10%), different cement content(4%,8%,12%,16%,20%), different number of freezing and thawing(5,10,15,20,25), The results show that the strength of the composite cement soil are significantly increase with increasing cement content, before and after freezing-thawing the strength loss and mass loss are increase with increasing freezing-thawing number and cement content.

Chitosan-modified magnetic nanoparticles were synthesized by an emulsion method and were characterized. The prepared chitosan-modified magnetic nanoparticles exhibit excellent adsorption performance for Cr(iii) at pH 9 and total Cr (Cr(iii) and Cr(vi)) at pH 6. Therefore, a new method by combining magnetic solid phase extraction with inductively coupled plasma optical emission spectrometry was developed for the speciation of Cr(iii) and Cr(vi) in environmental water samples. The parameters affecting extraction and desorption of the target chromium species, such as pH, extraction time, sedimentation time and sample volume, were investigated and the optimized conditions were established. With a preconcentration factor of 100-fold, the limits of detection (LODs) were 0.02 and 0.03 ng mL−1with the relative standard deviations of 4.8% and 5.6% (n= 7, c= 1 ng mL−1) for Cr(iii) and Cr(total), respectively. The method was successfully applied to analyze East Lake water (Wuhan) and tap water at the campus of Wuhan University. In order to validate the accuracy of the proposed method, the certified reference material GSBZ50009-88 was analyzed, and the determined values were in good agreement with the certified values. The proposed method, with the merits of simple operation, rapid adsorption/desorption dynamics, high enrichment factor and low LODs, is suitable for the speciation of inorganic chromium in environmental water samples.