Cyclobutanones are synthetically versatile compounds that often requires extensive effort to access. Herein, we report a facile synthesis of cyclobutanones based on the C(sp
3
)-H insertion chemistry ...of oxidatively generated gold carbenes. A range of cyclobutanones was obtained in synthetically useful yields from substrates with minimal structural prefunctionalization. This discovery reveals new synthetic utilities of gold-catalyzed oxidative transformations of alkynones.
Insertion into unactivated C(
sp
3
)-H bonds by metal carbenes/carbenoids is a reaction of significant synthetic value. In this study, easily accessible alkynone substrates are converted to strained cyclobutanones via such an insertion by an oxidatively generated β-diketone-α-gold carbene. This reaction serves as a benign and more synthetically expedient alternative to diazo-based approaches.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
The large-scale accumulation of shield waste mud (SWM) generated during urban subway construction is prone to cause potential environmental problems. A new low-carbon curing modified material, i.e., ...OPC-MCA, was firstly prepared to economically and environmentally treat SWM by partially replacing ordinary Portland cement (OPC) with a composite external admixture. Thereafter, laboratory curing experiments of SWM taken from the Jinan Jile Road Yellow River Tunnel were conducted by controlling OPC-MCA at a 20% dosage and basalt fiber (BF) at different dosages (0–1.05%). The appearance, mass and P-wave velocity of the cured specimens were characterized and the compression and shear strength tests were carried out. In addition, X-ray computed tomography (CT) and scanning electron microscope (SEM) analyses were performed to comprehensively assess the resistance of OPC-MCA cured SWM exposed to dry-wet (d-w) cycles with different BF dosages. The results confirmed that the optimal BF dosage for specimens that did not undergo d-w cycles was 0.45%, resulting in a 16.67% increase in compressive strength and a 51.56% increase in shear strength. The addition of BF enhanced the resistance of specimens to d-w cycles and reduced the deterioration rates of mass, P-wave velocity, and mechanical properties. The hydrophilic expansion property of clay minerals significantly contributed to strength degradation and pore deformation of cured SWM specimens. The development degree of microscopic cracks and pores in cured SWM specimens was significantly affected by both the dosage of BF and the number of d-w cycles. By incorporating BF, the volume and connectivity of cracks and pores were reduced, the formation of small-sized pores was decreased, and the expansion of cracks was inhibited throughout the cycling process.
•The shield waste mud was treated with OPC-MCA combined basalt fiber (BF).•Specimens cured by BF at different dosages were subjected to dry-wet cycles.•Compressive and shear strengths and microstructural changes were tested.•The addition of BF reduced the formation of small-sized pores.•The addition of BF reduced the pore and crack volumes and their connectivity.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The development of a highly efficient heterogeneous catalysis process for the hydrolysis of cellulose to reducing sugars (RSs) and especially 5-hydroxymethylfurfural (HMF) in water is highly ...anticipated for large-scale use of cellulosic biomass in the future. Herein, a bamboo-derived biochar sulfonic acid bearing polyamide (BCSA-PA) designed by us was found to show much higher catalytic activity, better repeatability and especially HMF yield for microwave-assisted such hydrolysis compared to the PA-free BCSA, achieving 25.60% RSs and 23.10% HMF yields with 4.71 turnover number (TON) under optimal conditions. Also, its TON value (2.58) for the conversion of cellulose into HMF was much higher than those obtained from it-catalyzed transformation of glucose (TON, 1.44) and especially fructose (TON, 0.79). The BCSA-PA showing an excellent catalysis performance in cellulose hydrolysis is likely due to the following two reasons: (1) the BCSA and especially BCSA-PA, as supported by glucose and cellobiose adsorption experiments, have a stronger affinity to β-1,4-glycosidic bonds of cellulose than two monosaccharides, thereby leading to the highly-efficient hydrolysis of cellulose on the SO
3
H groups. (2) The acid–base synergistic catalysis between the SO
3
H and PA groups of BCSA-PA may be responsible for its higher HMF selectivity and excellent repeatability in water medium. The current work highlights new opportunities for the direct production of 5-HMF from glucose and especially cellulose.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The prediction of the production capacity of the enhanced geothermal system (EGS) is crucial for the extraction of geothermal resources. To better optimize the EGS project, it is necessary to make a ...reasonable prediction of the heat-production capacity of the geothermal site. This work aims to provide an accurate and simpler calculation method based on geometric split-productivity superposition of multi-well EGS productivity prediction in large geothermal fields to guide the design and optimization of EGS in large geothermal fields. First, based on a complex potential function, a steady-state seepage model of well groups is established in a limited plane. After splitting the flow field according to the flow law in the plane, the productivity control area of a single injection well is obtained. The splitting method of the small well-group is obtained, which uses the bisector of the angle between the adjacent injection wells and the production well. Then, the three-dimensional finite-element numerical models of the EGS are established for the small well-group in the limited area and the single-pore double-well after splitting. By analyzing the heat production performance of the two methods, the correctness of the splitting method of the plane small well-group is verified. These models are based on the mathematical model of flow–heat coupling composed of the Dupuit formula, groundwater-flow equation, and porous-medium heat-transfer equation, combined with the split production-capacity-control area of the single injection well and the influence of the production well eccentricity. The comparison of the heat-production performances of the two methods shows that the maximum relative error rate of the two results does not exceed 9% and that the fluctuation trend of the corresponding double-well heat exchange EGS is consistent with the whole heat exchange EGS. These results prove that the splitting method has good applicability of predicting the EGS productivity of well groups in a limited area by calculating the superposition of the double-well EGS productivity after splitting. The total capacity of the well-group EGS in a limited area is equal to the sum of the capacity of each split double-well heat exchange EGS. Furthermore, this paper also provides proof of the rationality of the split method.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Renal ischemia-reperfusion is a major cause of acute kidney injury, a disease currently without effective treatments. Irisin was initially identified as an important factor produced by muscles to ...mediate the health benefits of exercise, and recent work has further suggested its protective effect against lung and liver injury. However, the role of Irisin in kidney diseases, including renal ischemia-reperfusion injury (IRI), remains unknown. In the present study, we found that the Irisin precursor, fibronectin type III domain-containing protein 5 (Fndc5), was induced in renal tubules in a mouse model of renal IRI and in cultured mouse renal proximal tubular cells subjected ATP depletion injury. Functionally, silencing Fndc5 in cultured proximal tubular cells increased the sensitivity to ATP depletion-induced apoptosis, whereas both Fndc5 overexpression and supplementation of recombinant Irisin alleviated ATP depletion-induced apoptosis. In vivo, administration of recombinant Irisin dramatically attenuated kidney dysfunction, tissue damage, tubular cell apoptosis, and inflammation during renal IRI in mice. Mechanistically, Irisin suppressed the activation of p53 in renal IRI, a critical factor in tubular cell death. Together, these results indicate that Irisin is induced in renal IRI as a protective mechanism for renal tubular cells, suggesting the therapeutic potential of recombinant Irisin in renal IRI and related kidney diseases.
•Renal tubular cells express FNDC5/Irisin, which is induced by renal ischemia-reperfusion.•Upon induction, FNDC5/Irisin protects against tubular cell injury in renal ischemia-reperfusion.•Recombinant Irisin has a therapeutic potential for renal ischemia-reperfusion injury.•FNDC5/Irisin suppresses p53 activation in renal ischemia-reperfusion injury.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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•Three s-triazine reactive disperse dyes were synthesized.•Sustainable and waterless dyeing of polyester-cotton blends was investigated.•One-bath dyeing was successfully realized in ...supercritical CO2.•Dyeing mechanism of polyester-cotton blends was proposed.
Traditional water medium dyeing of polyester-cotton fabrics consumes more water and energy, and causes serious environmental pollution in comparison with one-bath dyeing of single component fiber. To achieve sustainable dyeing of polyester-cotton blends, three reactive disperse dyes with s-triazine reactive group were synthesized, and supercritical CO2 was used as solvent to conduct the waterless dyeing. The results showed that one-bath dyeing of polyester-cotton blends could be successfully realized with the synthesized dyes. Dyeing performance of the synthesized dyes was constantly improved with the extension of carbon chain on aniline. Compared with other two dyes, the optimal color strength of polyester-cotton blends was obtained with dye 3 using dimethylsulfoxide as co-solvent, and K/S values up to 6.4 were obtained at 100 °C, 20 MPa and 120 min with a dimethylsulfoxide concentration of 80 %. σK/S values below 0.14 and washing and rubbing fastness above 4 were displayed for the colored samples. In addition, dyeing mechanism of polyester-cotton fabrics with the synthesized dyes was discussed combined with FT-IR measurement and stripping experiments.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Numerous studies have demonstrated the potential of banana blossom polyphenols as antioxidants and antifungal agents. However, their application in the food field is extremely limited due to their ...vulnerability to environmental conditions. This study aims to increase the stability of banana blossom polyphenols and explore their potential in food preservation, particularly against fungal infections. To achieve this, β-lactoglobulin@ferulic acid-quercetin-vanillic acid nanoparticles (N-β-LG@FA-QT-VA) with a particle size of 74.5–80.7 nm were successfully obtained using β-lactoglobulin (β-LG) as the encapsulating material, combined with protein heating modification and emulsification-evaporation techniques. The encapsulation process resulted in a significant increase in antioxidant activity, with an improvement of 42.3% over the free polyphenols. Furthermore, N-β-LG@FA-QT-VA nanoparticles displayed significantly higher antifungal activity and fruit preservation abilities compared to β-LG and FA-QT-VA mixtures. They effectively inhibited the germination and expansion of Penicillium digitatum, a common fruit pathogen. Applying this knowledge, these nanoparticles were tested on orange fruits inoculated with P. digitatum. A successful delay in green mold infection and decay was observed, demonstrating the potential of N-β-LG@FA-QT-VA nanoparticles as a natural alternative to synthetic fungicides, all while maintaining fruit quality.
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•β-lactoglobulin enhanced the antioxidant activity of polyphenols.•N-β-LG@FA-QT-VA had remarkable sustained-release properties for polyphenols.•N-β-LG@FA-QT-VA hindered Penicillium digitatum germination in vitro.•N-β-LG@FA-QT-VA delayed green mold infection in orange fruits.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Neuropsychiatric involvement is one of the major concerns in systemic lupus erythematosus (SLE). The therapeutic effect of intrathecal treatment of methotrexate and dexamethasone has been ...investigated in some exploratory studies, but its influence on the long-term prognosis of neuropsychiatric SLE (NPSLE) remains unknown.
This was a propensity score-matched retrospective study. Outcomes at discharge and time free from NPSLE relapse or death were evaluated by multivariate logistic regression, survival analysis, and Cox regression as appropriate.
Among 386 hospitalized patients with NPSLE, the median IQR age was 30.0 23.0-40.0 years, and 342 patients (88.4%) were female. Of those, 194 patients received intrathecal treatment. Patients in the intrathecal treatment group had higher Systemic Lupus Erythematosus Disease Activity Index 2000 scores (median 17 vs. 14 points, IQR 12-22 vs. 10-19 points, P <0 .001) and were more likely to receive methylprednisolone pulse therapy (71.6% vs. 49.5%, P < 0.001) than those who did not receive intrathecal therapy. Intrathecal treatment was associated with a higher probability of survival and being free from NPSLE relapse than control treatment among the 386 unmatched patients (P =0.042 by log-rank test) and within 147 propensity score-matched pairs (P =0.032 by log-rank test). In the subgroup of NPSLE patients with increased levels of protein in cerebrospinal fluid, intrathecal treatment had a positive influence on their prognosis (P < 0.001).
Intrathecal treatment of methotrexate and dexamethasone was associated with a more favorable prognosis of NPSLE and may serve as a valuable additional therapy for NPSLE patients, especially for those with elevated levels of protein in cerebrospinal fluid.
Reinforcement learning methods as a promising technique have achieved superior results in the motion planning of free-floating space robots. However, due to the increase in planning dimension and the ...intensification of system dynamics coupling, the motion planning of dual-arm free-floating space robots remains an open challenge. In particular, the current study cannot handle the task of capturing a non-cooperative object due to the lack of the pose constraint of the end-effectors. To address the problem, we propose a novel algorithm, EfficientLPT, to facilitate RL-based methods to improve planning accuracy efficiently. Our core contributions are constructing a mixed policy with prior knowledge guidance and introducing ‖⋅‖∞ to build a more reasonable reward function. Furthermore, our method successfully captures a rotating object with different spinning speeds.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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