The recycled fine-powder (RFP), produced during the recycling process, will induce a serious impact on the environment with improper disposition. A potential green way to reuse RFP is to add it as ...supplementary cementitious material in concrete. The effects of RFP on the hydration, microstructure, shrinkage and mechanical properties of ultra-high performance engineered cementitious composites (UHP-ECC) with different replacement ratios up to 50% were investigated. The hydration kinetics were compared among the different replacement ratios using the isothermal calorimetry, which demonstrated an accelerating effect of RFP to the hydration of UHP-ECC matrix. The phase development was quantified by the thermal gravimetric analysis and proved the pozzolanic effect of RFP. The compressive and tensile properties of UHP-ECCs were obtained at 3, 7 and 28 days, respectively, to trace their development along the curing ages. The addition of RFP significantly reduced the autogenous shrinkage of UHP-ECC. Besides, the single fiber pullout test was investigated to quantify the influence of RFP at the fiber level. The environmental scanned electron microscope analysis was conducted to study the morphology of PE fiber at the fracture surface.
•Up to 50% of cement was replaced by recycled fine powder (RFP) without significant loss in mechanical properties•Effects of RFP on the hydration, microstructure, shrinkage and mechanical properties of UHP-ECC were investigated•A linkage of micro-mechanical scale at the fiber level and to macro-mechanical scale at the composite level was established.
•The tensile, compressive and flexural behaviors of UHP-ECC were systematically investigated.•UHP-ECC combines the strain-hardening and multiple crack characteristics and the high strength of mortar ...matrix.•Ultra-high-molecular-weight polyethylene (PE) fibers with a high aspect ratio were deployed.•The digital image correlation (DIC) technique was utilized to monitor the crack patterns during the tests.•Scanning electron microscope (SEM) analysis was conducted to understand the microstructure of UHP-ECC.
Ultra-high performance engineered cementitious composites (UHP-ECC), which combines the strain-hardening and multiple crack characteristics and the high strength of mortar matrix, was investigated in this study. The tensile strength and elongation of the UHP-ECC achieved were 20 MPa and 8.7%, respectively. For the production of UHP-ECC, ultra-high-molecular-weight polyethylene (PE) fibers were deployed to reinforce the ultra-high strength mortar while special attention was paid to the mix process to ensure satisfactory fiber dispersion. The tensile stress-strain curves, the compressive strength and elastic modulus, and the flexural behavior of UHP-ECC were investigated to understand its mechanical performance. The digital image correlation (DIC) technique was utilized to monitor the crack patterns of UHP-ECC during the tensile and flexural tests. In addition, Scanning electron microscope (SEM) analysis was conducted to achieve an in-depth understanding of the microstructure of UHP-ECC.
AbstractThis research developed an ultra-high-performance engineered cementitious composite (UHP-ECC), which combines the properties of strain-hardening, multiple cracking, and high mechanical ...strength. The compressive strength of the UHP-ECC reached 150 MPa at 28 days under standard curing conditions, whereas the tensile strength and strain capacity of the UHP-ECC were 18 MPa and 8%, respectively. Different fiber volumetric ratios and geometries (fiber length and diameter) were used to investigate the influences of fiber-reinforcement parameters on the mechanical and crack-pattern properties of UHP-ECC, including the tensile strength, strain capacity, strain energy, crack number, and crack spacing. It was found that the fiber reinforcement parameters significantly influence both the mechanical properties and crack-patterns of UHP-ECC. Based on the test results, a bilinear tensile stress–strain model was proposed for UHP-ECC and its accuracy was demonstrated through comparisons with the test results.
Tuning the emissive color changes of lanthanide (Ln) complexes is an important and appealing project for promoting the applications of Ln-complexes. A solvothermal reaction of 4-cyano-3-methylbenzoic ...acid (HL) and Ln(NO
3
)
3
·6H
2
O affords three isostructural Ln-complexes Eu(L)
3
(H
2
O)
2
n
(
1-Ln
) (Ln = Eu, Gd and Tb) with one-dimensional chain structures.
1-Eu
and
1-Tb
show bright red and green emissions with absolute quantum yields of 3.06% and 11.96%, respectively, and the energy transfer was analyzed in detail through combined calculations. Interestingly, a series of heterometallic doped
1-Tb
x
Eu
1−
x
coordination polymers were also obtained by mixing different ratios of Eu
3+
and Tb
3+
ions, which possess continuous luminescent color changes from green to yellow, orange and red. In addition,
1-Eu
exhibits high quenching efficiency and low detection limit (∼10
−4
M) for the simultaneous sensing of MnO
4
−
, CrO
4
2−
and Cr
2
O
7
2−
ions in water.
Three synthesized Ln-CPs show tunable emission colors through bimetallic doping and sensing for MnO
4
−
, CrO
4
2−
and Cr
2
O
7
2−
ions in water.
A honeycomb MOF, based on rare Ni6 trigonal-prismatic supermolecular building blocks, was fabricated by utilizing an unexploited 1,1′-biphenyl-3,3′,5,5′-tetracarboxylic acid linker with –NH2 ...substituent groups. The MOF contains novel building blocks and an enchanting structure, and also exhibits water-stable characteristics. Uniquely, the accessible adsorption sites, arising due to the high-density Lewis-basic amino-coordinated groups and uncoordinated carboxylate O atoms in the pores, endow the MOF with excellent capture and separation capabilities for C2H2.
Abstract
The remarkable advances in next-generation sequencing technology have enabled the wide usage of sequencing as a clinical tool. To promote the advance of precision oncology for breast cancer ...in China, here we report a large-scale prospective clinical sequencing program using the Fudan-BC panel, and comprehensively analyze the clinical and genomic characteristics of Chinese breast cancer. The mutational landscape of 1,134 breast cancers reveals that the most significant differences between Chinese and Western patients occurred in the hormone receptor positive, human epidermal growth factor receptor 2 negative breast cancer subtype. Mutations in p53 and Hippo signaling pathways are more prevalent, and 2 mutually exclusive and 9 co-occurring patterns exist among 9 oncogenic pathways in our cohort. Further preclinical investigation partially suggests that
NF2
loss-of-function mutations can be sensitive to a Hippo-targeted strategy. We establish a public database (Fudan Portal) and a precision medicine knowledge base for data exchange and interpretation. Collectively, our study presents a leading approach to Chinese precision oncology treatment and reveals potentially actionable mutations in breast cancer.
Methane is supersaturated in surface seawater and shallow coastal waters dominate global ocean methane emissions to the atmosphere. Aerobic methane oxidation (MOx) can reduce atmospheric evasion, but ...the magnitude and control of MOx remain poorly understood. Here we investigate methane sources and fates in the East China Sea and map global MOx rates in shallow waters by training machine-learning models. We show methane is produced during methylphosphonate decomposition under phosphate-limiting conditions and sedimentary release is also source of methane. High MOx rates observed in these productive coastal waters are correlated with methanotrophic activity and biomass. By merging the measured MOx rates with methane concentrations and other variables from a global database, we predict MOx rates and estimate that half of methane, amounting to 1.8 ± 2.7 Tg, is consumed annually in near-shore waters (<50 m), suggesting that aerobic methanotrophy is an important sink that significantly constrains global methane emissions.
This paper investigates the flexural performance of a series of RC beams externally bonded with carbon fiber-reinforced polymer (CFRP) grid-reinforced engineered cementitious composite (ECC) matrix. ...A total of 15 RC beams, including three control and twelve strengthened, were prepared and tested. The test variables included the longitudinal reinforcement ratio, the strengthening configurations that consisted of different cementitious matrices (ECC versus epoxy mortar), different installation methods (prefabricated versus cast-in-place), and different stiffness of CFRP grids. The test results showed that ECC is an ideal cementitious matrix for the strengthening applications where FRP grids are used as the external reinforcement. The flexural strengthening configuration using the epoxy adhesive to bond prefabricated CFRP grid-reinforced ECC plate proved to be the most efficient solution. For such configuration, the plate-end debonding can be avoided and the mid-span debonding can be almost suppressed. Flexural capacity analysis was conducted and demonstrated that the plane section assumption is valid and the full strength composite action can be nearly achieved for the strengthening system. The average ratio of the predicted peak loads to the experimental ones of the strengthened RC beams was 1.05.
Based on a double-layered semiconductor nanostructure (DLSN)-InSb/GaSb, we propose a controllable electron-spin filter for spintronics device applications. Electron-spin polarization is induced by ...Rashba spin-orbit coupling inside the DLSN. Both magnitude and sign of spin polarization ratio can be manipulated by externally-applied electric field or the semiconductor-layer thickness.
The rising demand for energy density of cathodes means the need to raise the voltage or capacity of cathodes. Transition metal (TM) doping has been employed to enhance the electrochemical properties ...in multiple aspects. The redox voltage of doped cathodes usually falls in between the voltage of undoped layered cathodes. However, we found anomalous redox features in NaTi1−yVyS2. The first discharge platform potential (2.4 V) is significantly higher than that of undoped NaTiS2 and NaVS2 (both around 2.2 V), and the energy density is raised by 15 %. We speculate that the anomalous voltage is mainly attributed to the strong hybridization in the Ti−V−S system. Ti3+ and V3+ undergo charge transfer and form a more stable Ti (t2g0eg0) and V (t2g3eg0) electronic configuration. Our results indicate that higher voltage of cathode materials could be achieved by strong TM‐ligand covalency, and this conclusion provides possible opportunities to explore high voltage materials for future layered cathodes.
The redox voltage of doped cathodes usually falls in between the voltage of undoped layered cathodes. However, anomalous redox features were found in NaTi1−yVyS2. The discharge potential is 0.2 V higher than that of undoped cathodes. It is speculated that the anomalous voltage is mainly attributed to the strong covalency in the Ti−V−S system. Ti3+ and V3+ undergo charge transfer and form a more stable Ti (t2g0eg0) and V (t2g3eg0) electronic configuration.
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