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Replacement of Portland cement (PC) by fly ash (FA) is currently limited to 15–30% by mass, mainly due to low early age strength development of concrete. This research uses calcium formate (Ca(HCO2)2; CF) as an admixture to high-volume FA (HVFA) composites to improve its strength properties. HVFA represents 60–70% of cement replaced by FA and dosage of CF varies from 0.5% up to high dosage of 9% of cement content. Compressive strength, isothermal calorimetry, thermogravimetric analysis, X-ray diffraction and scanning electron microscopy were conducted to investigate the effects of CF on hydration and microstructural aspects. The results show that both HVFA pastes with 60% and 70% FA achieved the highest strength at the CF dosage of 3%. At the age of 28 days, adding 3% CF to HVFA mixes led to higher consumption of FA as well as higher formation of calcium hydroxide (Ca(OH)2), calcium silicate hydrates, calcium carbonate (CaCO3) and ettringite, which contribute to the increase of strength. The addition of very high dosages of CF at 9% increased the hydration of tricalcium aluminate but could hinder the hydration of tricalcium silicate in both PC and HVFA pastes with 60% and 70% FA.

The Shatsky Rise ridge-ridge-ridge triple junction is an ancient triple junction in the Western Pacific Ocean whose initial geodynamic process is poorly understood and can only be inferred based on indirect geological and geophysical constraints. In this paper, we present three-dimensional numerical models that simulate the Shatsky Rise triple junction and calculate its coupled mantle flow and temperature structure. The mantle flow velocity field shows several distinctive features: 1) stronger mantle upwelling closer to the ridge axis and triple junction; 2) greater upwelling velocity at the faster-spreading ridges; and 3) the most significant increase in upwelling velocity for the slowest-spreading ridge toward the triple junction. The calculated mantle temperature field also reveals distinctive characteristics: 1) sharp increases in the mantle temperature with depth and increases toward the spreading ridges and triple junction; 2) the faster-spreading ridges are associated with higher temperatures at depth and identical distances from the triple junction; and 3) the slowest-spreading ridge shows the greatest increase in the along-ridge-axis temperature toward the triple junction. Compared to many present-day triple junctions with slower spreading rates, the along-ridge-axis velocity and thermal fields of the Shatsky Rise are more altered due to the presence of the triple junction.

Steel fibre (SF) reinforcement has been shown to improve the ductility of high strength concrete (HSC), which is known to be brittle. Research conducted to date on steel fibre reinforced concrete and its effects have emphasised post-failure performance and cracking mechanism. The difficulty in predicting the behaviour of fibres is due to the randomly distributed nature of the material within the matrix leading to a probability distribution of results. Published literature has shown a benefit of adding steel fibres in terms of the ductility performance of structures. Clearly, there is a potential for such material as replacement of conventional steel reinforcement. This study proposes a theoretical model of evaluating the potential of using steel fibres as a replacement material to conventional steel reinforcement bars based on the case study, laboratory and theoretical methodologies. The compressive strength of the concrete at key dates, the effective fibre cross-sectional were measured, and a prediction model was created based on the measurement parameters. The use of four-point flexural testing, standard compressive testing and software image modelling provided the study with relevant data used to analyse and compare to the prediction. Greater ductility performance and toughness were observed with increased fibre volumes, confirming proposed predictions and conclusion drawn from published literature. No consistent or conclusive correlations between fibre volumes and the compressive strength of concrete were found. A relationship between fibre volumes and predicted moment capacities of steel fibre reinforced concrete beams was found based on the proposed theoretical flexural analysis method.

The orthogonal supersegment of the ultraslow-spreading Southwest Indian Ridge at 16°–25°E is characterized by significant along-axis variations of mantle potential temperature. A detailed analysis of multibeam bathymetry, gravity, and magnetic data were performed to investigate its variations in magma supply and crustal accretion process. The results revealed distinct across-axis variations of magma supply. Specifically, the regionally averaged crustal thickness reduced systematically from around 7 Ma to the present, indicating a regionally decreasing magma supply. The crustal structure is asymmetric in regional scale between the conjugate ridge flanks, with the faster-spreading southern flank showing thinner crust and greater degree of tectonic extension. Geodynamic models of mantle melting suggested that the observed variations in axial crustal thickness and major element geochemistry can be adequately explained by an eastward decrease in mantle potential temperature of about 40°C beneath the ridge axis. In this work, a synthesized model was proposed to explain the axial variations of magma supply and ridge segmentation stabilities. The existence of large ridge-axis offsets may play important roles in controlling melt supply. Several large ridge-axis offsets in the eastern section (21°–25°E) caused sustained along-axis focusing of magma supply at the centers of eastern ridge segments, enabling quasi-stable segmentation. In contrast, the western section (16°–21°E), which lacks large ridge-axis offsets, is associated with unstable segmentation patterns.

Hypertrophic scarring, which is characterized by excessive extracellular matrix deposition and abnormal fibroblast homeostasis, is an undesirable outcome of dermal wound healing. Once formed, the scar will replace the normal function of local skin, and there are few noninvasive clinical treatments that can cure it. Se@SiO

This study investigates low cement quaternary blend HVFA concrete mixes utilizing up to 80% cement replacement using fly ash, hydrated lime and nano-silica. The optimized concrete mixes achieved a compressive strength of 55 MPa and 48 MPa, for HVFA-65 and HVFA-80 concretes, respectively. Additional fly ash and hydrated lime dosage in HVFA concrete increased the rate of hydration of the C3A and C4AF phases but decreased the hydration of the C3S phase. This resulted in lower early age strength development in the HVFA concrete than occurs in PC concrete but significantly higher than for fly ash and hydrated lime alone. The addition of the nano-silica resulted in an increase in C–S–H gel incorporation of tetrahedrally coordinated aluminium (AlIV) into the HVFA concrete and the substitution of Si by Al in the C–S–H gel, leading to an increase in compressive strength in the HVFA concrete. Early age carbonation was increased with a higher of fly ash percentage. However, the reaction products dissolved in the pore water to form calcium bicarbonate with time.

We analyzed seafloor morphology and geophysical anomalies of the Southeast Indian Ridge (SEIR) to reveal the remarkable changes in magma supply along this intermediate fast-spreading ridge. We found systematic differences of the Australian-Antarctic Discordance (AAD) from adjacent ridge segments with the residual mantle Bouguer gravity anomaly (RMBA) being more positive, seafloor being deeper, morphology being more chaotic, M factors being smaller at the AAD. These systematic anomalies, as well as the observed Na8.0 being greater and Fe8.0 being smaller at AAD, suggest relatively starved magma supply and relatively thin crust within the AAD. Comparing to the adjacent ridges segments, the calculated average map-view M factors are relatively small for the AAD, where several Oceanic Core Complexes (OCCs) develop. Close to 30 OCCs were found to be distributed asymmetrically along the SEIR with 60% of OCCs at the northern flank. The OCCs are concentrated mainly in Segments B3 and B4 within the AAD at ≈124°–126°E, as well as at the eastern end of Zone C at ≈115°E. The relatively small map-view M factors within the AAD indicate stronger tectonism than the adjacent SEIR segments. The interaction between the westward migrating Pacific mantle and the relatively cold mantle beneath the AAD may have caused a reduction in magma supply, leading to the development of abundant OCCs.

We conducted a detailed analysis of along-trench variations in the flexural bending of the subducting Pacific Plate at the Tonga-Kermadec Trench. Inversions were conducted to obtain best-fitting solutions of trench-axis loadings and variations in the effective elastic plate thickness for the analyzed flexural bending profiles. Results of the analyses revealed significant along-trench variations in plate flexural bending: the trench relief (W0) of 1.9 to 5.1 km; trench-axis vertical loading (V0) of −0.5×1012 to 2.2×1012 N/m; axial bending moment (M0) of 0.1×1017 to 2.2×1017 N; effective elastic plate thickness seaward of the outer-rise region ($$T_{\rm{e}}^{\rm{M}}$$) of 20 to 65 km, trench-ward of the outer-rise ($$T_{\rm{e}}^{\rm{m}}$$) of 11 to 33 km, and the transition distance of 20 to 95 km. The Horizon Deep, the second greatest trench depth in the world, has the greatest trench relief (w0 of 5.1 km) and trench-axis loading (V0 of 2.2×1012 N/m); these values are only slightly smaller than that of the Challenger Deep (W0 of 5.7 km and V0 of 2.9×1012 N/m) and similar to that of the Sirena Deep (W0 of 5.2 km and V0 of 2.0×1012 N/m) of the Mariana Trench, suggesting that these deeps are linked to great flexural bending of the subducting plates. Analyses using three independent methods, i.e., the $$T_{\rm{e}}^{\rm{M}}$$/$$T_{\rm{e}}^{\rm{m}}$$ inversion, the flexural curvature/yield strength envelope analysis, and the elasto-plastic bending model with normal faults, all yielded similar average Te reduction of 28%–36% and average Te reduction area $${S_{\Delta {T_{\rm{e}}}}}$$ of 1 195–1 402 km2 near the trench axis. The calculated brittle yield zone depth from the flexural curvature/yield strength envelope analysis is also consistent with the distribution of the observed normal faulting earthquakes. Comparisons of the Manila, Philippine, Tonga-Kermadec, Japan, and Mariana Trenches revealed that the average values of $$T_{\rm{e}}^{\rm{M}}$$ and $$T_{\rm{e}}^{\rm{m}}$$ both in general increase with the subducting plate age.

We quantify flexural deformation of subducting oceanic plates at a global array of 15 ocean trenches, using a new approach of modelling spatial variations in flexural bending shape and curvature. T...

This paper reports on the effect of addition of nano-calcium silicate hydrate (nano-CSH) seeds on the early-age strength development and microstructural evolution of concrete containing hig...

Central nervous system lymphoma (CNSL) is an aggressive lymphoma. Orelabrutinib, an oral Bruton tyrosine kinase inhibitor, is a new treatment strategy for CNSL. This study aims to evaluate the efficacy and safety of orelabrutinib-based regimens in the treatment of patients with CNSL.Twenty-three patients with CNSL were included in this retrospective study. All patients received the orelabrutinib-based regimen. Efficacy was evaluated based on investigators' assessment of overall response rate (ORR), complete response/unconfirmed complete response (CR/CRu), partial response (PR), stable disease (SD), progressive disease (PD), duration of response (DOR), progression-free survival (PFS) and overall survival (OS). The safety of orelabrutinib-based regimens has also been evaluated.A total of 17.39% of patients received orelabrutinib-based regimens for consolidation therapy, and 82.61% of patients for induction therapy (4 newly diagnosed CNSL, 15 relapsed/refractory CNSL). In the newly diagnosed CNSL group, the ORR was 100% (1 CR, 1 CRu, 2 PR). The 6-month DOR rate, 6-month PFS rate, and 6-month OS rate were 100%, 100%, and 100%, respectively. Of the 15 relapsed/refractory CNSL patients, five therapy regimens were applied (orelabrutinib, n = 3; orelabrutinib/immunotherapy, n = 3; orelabrutinib/chemotherapy, n = 2; orelabrutinib/immunochemotherapy, n = 6; orelabrutinib/radiotherapy, n = 1). The ORR was 60.00% (4 CR, 5 PR). The 6-month DOR rate, 6-month PFS rate, and 6-month OS rate were 92.30%, 67.70%, and 70.00%, respectively. Twenty-one patients reported adverse events (AEs), and 6 patients experienced grade ≥ 3 AEs.Orelabrutinib-based regimens were efficacious and well-tolerated in patients with CNSL. These combined therapies offer a new potential therapeutic strategy for patients with CNSL.

There are large volumes of lead-zinc tailings (LZT) produced in China and elsewhere in the world. LZT disposal to the landfill is problematic and causes many environmental issues. The objec...

Optical interference is not only a fundamental phenomenon that has enabled new theories of light to be derived but it has also been used in interferometry for the measurement of small displacements, refractive index changes and surface irregularities. In a two-beam interferometer, variations in the interference fringes are used as a diagnostic for anything that causes the optical path difference (OPD) to change; therefore, for a specified OPD, greater variation in the fringes indicates better measurement sensitivity. Here, we introduce and experimentally validate an interesting optical interference phenomenon that uses photons with a structured frequency-angular spectrum, which are generated from a spontaneous parametric down-conversion process in a nonlinear crystal. This interference phenomenon is manifested as interference fringes that vary much more rapidly with increasing OPD than the corresponding fringes for equal-inclination interference; the phenomenon is parameterised using an equivalent wavelength, which under our experimental conditions is 29.38 nm or about 1/27 of the real wavelength. This phenomenon not only enriches the knowledge with regard to optical interference but also offers promise for applications in interferometry., Comment: 16 pages, 6 figures

Vectorial structured light with spatially varying amplitude, phase, and polarization is reshaping many areas of modern optics, including nonlinear optics, as diverse parametric processes can be used to explore interactions between such complex vector fields, extending the frontiers of optics to new physical phenomena. However, the most basic nonlinear application, i.e., frequency conversion, still remains challenging for vectorial structured light since parametric processes are polarization dependent, leading to a change in the spatial topological structure of signals. In this work, to break this fundamental limit, we propose a novel conformal frequency conversion scheme that allows to maintain the full spatial structure of vectorial structured light in the conversion; and systematically examine its spatial polarization independence based on non-degenerate sum-frequency generation with type-0 phase matching. This proof-of-principle demonstration paves the way for a wide range of applications requiring conformal frequency conversion, and, particularly, to implement frequency interfaces with multimodal communication channels, high-dimensional quantum states, and polarization-resolved upconversion imaging., 15 pages with 10 figures

Quantum nonlinear interferometers (QNIs) can measure the infrared physical quantities of a sample by detecting visible photons. A QNI with Michelson geometry based on the spontaneous parametric down-conversion in a second-order nonlinear crystal is studied systematically. A simplified theoretical model of the QNI is presented. The interference visibility, coherence length, equal-inclination interference, and equal-thickness interference for the QNI are demonstrated theoretically and experimentally. As an application example of the QNI, the refractive index and the angle between two surfaces of a BBO crystal are measured using equal-inclination interference and equal-thickness interference., 20 pages, 9 figures

On-chip bright quantum sources with multiplexing ability are extremely high in demand for the integrated quantum networks with unprecedented scalability and complexity. Here, we demonstrate an ultrabright and broadband biphoton quantum source generated in a lithium niobate microresonator system.Without introducing the conventional domain poling, the on-chip microdisk produces entangled photon pairs covering a broad bandwidth promised by natural phase matching in spontaneous parametric down conversion.Experimentally, the multiplexed photon pairs are characterized by $30\ \rm nm$ bandwidth limited by the filtering system, which can be furthered enlarged.Meanwhile, the generation rate reaches $5.13\ {\rm MHz}/\upmu \rm W$ with a coincidence-to-accidental ratio up to $804$.Besides, the quantum source manifests the prominent purity with heralded single photon correlation $g_H^{(2)}(0)=0.0098\pm0.0021$ and energy-time entanglement with excellent interference visibility of $96.5\%\pm1.9\%$. Such quantum sources at the telecommunication band pave the way for high-dimensional entanglement and future integrated quantum information systems., 8 pages,4 figures

Cat states are systems in a superposition of macroscopically distinguishable states; this superposition can be of either classically or quantum distinct state, regardless of the number of particles or modes involved. Here, we constructed an experimental model that simulates an optical cat state by engineering the classical orbital angular momentum of light, referred to here as an analogous cat state (a-CS). In our scheme, the behaviors of the a-CS in position space show many similarities to the quantum version of the optical cat state in phase space, for example, movement, rotation, and interference. Experimentally, the a-CS, which has two spatially localized Gaussian intensity lobes, can be evolved from "kitten" to "cat" by engineering the acquired phase hologram. Additionally, we simulated the "decoherence" of the a-CS influenced by atmospheric turbulence. The a-CS provides a reliable tool for visualizing and studying the behaviors of quantum cat states in phase space., Comment: 9 pages, 7 Figures

SUMMARYWe have conducted the first passive Ocean Bottom Seismograph (OBS) experiment near the Challenger Deep at the southernmost Mariana subduction zone by deploying and recovering an array of 6 broad-band OBSs during December 2016–June 2017. The obtained passive-source seismic records provide the first-ever near-field seismic observations in the southernmost Mariana subduction zone. We first correct clock errors of the OBS recordings based on both teleseismic waveforms and ambient noise cross-correlation. We then perform matched filter earthquake detection using 53 template events in the catalogue of the US Geological Survey and find >7000 local earthquakes during the 6-month OBS deployment period. Results of the two independent approaches show that the maximum clock drifting was ∼2 s on one instrument (OBS PA01), while the rest of OBS waveforms had negligible time drifting. After timing correction, we locate the detected earthquakes using a newly refined local velocity model that was derived from a companion active source experiment in the same region. In total, 2004 earthquakes are located with relatively high resolution. Furthermore, we calibrate the magnitudes of the detected earthquakes by measuring the relative amplitudes to their nearest relocated templates on all OBSs and acquire a high-resolution local earthquake catalogue. The magnitudes of earthquakes in our new catalogue range from 1.1 to 5.6. The earthquakes span over the Southwest Mariana rift, the megathrust interface, forearc and outer-rise regions. While most earthquakes are shallow, depths of the slab earthquakes increase from ∼100 to ∼240 km from west to east towards Guam. We also delineate the subducting interface from seismicity distribution and find an increasing trend in dip angles from west to east. The observed along-strike variation in slab dip angles and its downdip extents provide new constraints on geodynamic processes of the southernmost Mariana subduction zone.

Multiphoton quantum states play a critical role in emerging quantum technologies and greatly improve our fundamental understanding of the quantum world. Integrated photonics is well recognized as an attractive technology offering great promise for the generation of photonic quantum states with high-brightness, tunability, stability, and scalability. Herein, we demonstrate the generation of multiphoton quantum states using a single-silicon nanophotonic waveguide. The detected four-photon rate reaches 0.34 Hz even with a low-pump power of 600 μW. This multiphoton quantum state is also qualified with multiphoton quantum interference, as well as quantum state tomography. For the generated four-photon states, the quantum interference visibilities are greater than 95%, and the fidelity is 0.78 ± 0.02. Furthermore, such a multiphoton quantum source is fully compatible with the on-chip processes of quantum manipulation, as well as quantum detection, which is helpful for the realization of large-scale quantum photonic integrated circuits (QPICs) and shows great potential for research in the area of multiphoton quantum science., Photonics: Pairing-up for next generation photonic quantum technologies Chinese scientists have developed a technique for generating photon-pairs for use in quantum devices, paving the way for a range of new photonic quantum technologies. Multi-photon quantum sources are critical for the development of new photonic quantum technologies, and drove Dao-Xin Dai and colleagues from Zhejiang University, in collaboration with researchers from the University of Science and Technology of China, to develop a technique that generates high-quality photonic quantum states. Using a method called spontaneous four-wave mixing, whereby three electromagnetic fields interact to produce a fourth field, the team created multi-photon quantum states in a silicon nanophotonic spiral waveguide. The technique produces bright, tunable, stable and scalable multi-photon quantum states, and is compatible with a current fiber and integrated circuit manufacturing processes, opening the door to new photonic quantum technologies in communications, computation, and imaging.

A new, world-class library has been built at China Agricultural University in Beijing, the oldest agricultural higher education institute in China. The new building’s attractive natural stone facades reflect both old and new, from bamboo writing slips to barcodes, while the dramatic internal space is user-friendly, energy-efficient and flexible. During construction, an innovative hybrid diaphragm walling solution was adopted due to the high groundwater level and restricted site. Building information modelling technology was also successfully used throughout design and construction, helping to improve construction quality and safety management.

Quantum entanglement is the key resource for quantum information processing. Device-independent certification of entangled states is a long standing open question, which arouses the concept of self-testing. The central aim of self-testing is to certify the state and measurements of quantum systems without any knowledge of their inner workings, even when the used devices cannot be trusted. Specifically, utilizing Bell’s theorem, one can infer the appearance of certain entangled state when the maximum violation is observed, e.g., to self-test singlet state using CHSH inequality. In this work, by constructing a versatile entanglement source, we experimentally demonstrate a generalized self-testing proposal for various bipartite entangled states up to four dimensions. We show that the high-quality generated states can approach the maximum violations of the utilized Bell inequalities, and thus, their Schmidt coefficients can be precisely inferred by self-testing them into respective target states with near-unity fidelities. Our results indicate the superior completeness and robustness of this method and promote self-testing as a practical tool for developing quantum techniques. Certifying entanglement, and even fully characterizing some quantum states, can be done even with devices that we don’t trust. Chuan-Feng Li and coworkers from University of Science and Technology of China (Hefei) have devised an improved method for quantum “self-testing”, meaning characterizing properties of quantum states (in particular entanglement, the notorious “spooky” quantum correlation) without assuming fully-correct functioning of the measurement apparatus, but based only on the measurements’ violation of mathematical inequalities that can happen only for specific quantum states. Li’s method was also tested experimentally on entangled photons, proving one of its main strengths: robustness with respect to imperfections. Self-testing would allow to strengthen even more the capabilities of quantum techniques for intrinsically-secure communication based on entanglement.

The plate flexure and normal faulting characteristics along the Tonga, Japan, Izu-Bonin and Mariana Trenches are investigated by combining observations and modeling of elastoplastic deformation of the subducting plate. The observed average trench relief is found to be the smallest at the Japan Trench (3 km) and the largest at the Mariana Trench (4.9 km), and the average fault throw is the smallest at the Japan Trench (113 m) and the largest at the Tonga Trench (284 m). A subducting plate is modeled to bend and generate normal faults subjected to three types of tectonic loading at the trench axis: vertical loading, bending moment, and horizontal tensional force. It is inverted for the solutions of tectonic loading that best fit the observed plate flexure and normal faulting characteristics of the four trenches. The results reveal that a horizontal tensional force (HTF) for the Japan Trench is 33%, 50% and 60% smaller than those of the Mariana, Tonga and Izu-Bonin Trenches, respectively. The normal faults are modeled to penetrate to a maximum depth of 29, 23, 32 and 32 km below the sea floor for the Tonga, Japan, Izu-Bonin and Mariana Trenches, respectively, which is consistent with the depths of relocated normal faulting earthquakes in the Japan and Izu-Bonin Trenches. Moreover, it is argued that the calculated horizontal tensional force is generally positively correlated with the observed mean fault throw, while the integrated area of the reduction in the effective elastic thickness is correlated with the trench relief. These results imply that the HTF plays a key role in controlling the normal faulting pattern and that plate weakening can lead to significant increase in the trench relief.

Municipal Solid Waste (MSW) management is a worldwide problem growing with the increase of global human population. The practice of incinerating garbage has ceased in some parts of the world because of air contamination and other public health issues. Environmental impact of landfilling is ever increasing. There is clearly a need to adopt cost-effective alternatives to treat MSW. This paper is a part of a major work that considers MSW based biomass as a partial replacement of sand in concrete. The product of the global work is an exciting and eco-friendly alternative for the building industry, especially concrete intended for certain types of applications in the construction industry such as temporary works. Here, in this paper, an overview of the state of the art on the topic is presented.

Engineering vector spatial modes of photons is an important approach for manipulating high-dimension photonic states in various quantum optical experiments. In this work, we demonstrate the generation of heralded single photons with well-defined vector spatial modes by using a self-stable polarizing interferometer comprising a spatial light modulator. Specifically, it is shown that, by carefully tailoring and compensating the spatial and temporal amplitudes of manipulated photons, one can exactly convert ultrafast single photons into desired spin-orbit states with an extremely high purity. This compact and robust device provides a versatile way for not only the generation, but also the manipulation and characterization of arbitrary photonic spin-orbit states.

Remotely switchable edge imaging is demonstrated on the basis of the metasurface illuminated by polarization-entangled photons., Metasurfaces consisting of engineered dielectric or metallic structures provide unique solutions to realize exotic phenomena including negative refraction, achromatic focusing, electromagnetic cloaking, and so on. The intersection of metasurface and quantum optics may lead to new opportunities but is much less explored. Here, we propose and experimentally demonstrate that a polarization-entangled photon source can be used to switch ON or OFF the optical edge detection mode in an imaging system based on a high-efficiency dielectric metasurface. This experiment enriches both fields of metasurface and quantum optics, representing a promising direction toward quantum edge detection and image processing with remarkable signal-to-noise ratio.