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The construction of the Strait Passage is an important part of improving the national comprehensive three-dimensional transportation network, one of the important strategic tasks of promoting the construction of a transportation power, and of special significance for China to construct a new production pattern. This paper focuses on the preliminary study of the Qiongzhou Strait cross-sea channel project, combs the research achievements of the Qiongzhou Strait channel over the years, and analyzes the necessity and feasibility of the Qiongzhou Strait channel construction. The study of the construction scheme of the Qiongzhou Strait channel, comparison and selection of the channel alignment, bridge and tunnel schemes, and highway and railway schemes respectively recommend to "plan once, construct by stages, and build the railway first" and construct midcourt railway of double-line in advance (reserve highway channels), and adopt the four hole parallel scheme of "double hole highway tunnel+single hole double line railway tunnel+service tunnel". It also puts forward suggestions for the construction of the Qiongzhou Strait from the aspects of construction opportunity, financing mode, construction concept, operation and maintenance plan, thematic research, etc. [ABSTRACT FROM AUTHOR]

Electroreduction of C[O.sub.2] into useful fuels, especially if driven by renewable energy, represents a potentially 'clean' strategy for replacing fossil feedstocks and dealing with increasing C[O.sub.2] emissions and their adverse effects on climate (1-4). The critical bottleneck lies in activating C[O.sub.2] into the C[O.sub.2.sup.*-] radical anion or other intermediates that can be converted further, as the activation usually requires impractically high overpotentials. Recently, electrocatalysts based on oxide-derived metal nanostructures have been shown (5-8) to enable C[O.sub.2] reduction at low overpotentials. However, it remains unclear how the electrocatalytic activity of these metals is influenced by their native oxides, mainly because microstructural features such as interfaces and defects (9) influence C[O.sub.2] reduction activity yet are difficult to control. To evaluate the role of the two different catalytic sites, here we fabricate two kinds of four-atom-thick layers: pure cobalt metal, and co-existing domains of cobalt metal and cobalt oxide. Cobalt mainly produces formate (HCO[O.sup.-]) during C[O.sub.2] electroreduction; we find that surface cobalt atoms of the atomically thin layers have higher intrinsic activity and selectivity towards formate production, at lower overpotentials, than do surface cobalt atoms on bulk samples. Partial oxidation of the atomic layers further increases their intrinsic activity, allowing us to realize stable current densities of about 10 milliamperes per square centimetre over 40 hours, with approximately 90 per cent formate selectivity at an overpotential of only 0.24 volts, which outperforms previously reported metal or metal oxide electrodes evaluated under comparable conditions (1,2,6,7,10). The correct morphology and oxidation state can thus transform a material from one considered nearly non-catalytic for the C[O.sub.2] electroreduction reaction into an active catalyst. These findings point to new opportunities for manipulating and improving the C[O.sub.2] electroreduction properties of metal systems, especially once the influence of both the atomic-scale structure and the presence of oxide are mechanistically better understood., To explore the catalytic role of metal sites and metal oxide sites, we first construct a system containing a 4-atom-thick metal layer and then create the corresponding metal oxide on [...]

Slope instability processes occur widely on the underwater slopes of the Yellow River delta during storms. Roughly circular depressions on the upper delta front in water depths of 4 to 8 m have been detected by acoustic surveying and their processes were observed in the laboratory. This paper analyzes the properties of geomorphic and acoustic profiles of the upper delta front and compares the engineering geologic properties of samples from the disturbed and undisturbed areas. The results indicate that the weak superficial mass could oscillate with waves and the oscillation weakened the surrounding soil under the cyclic loading. The stratum was disturbed or even destroyed with depth, the area of the slide mass enlarged gradually, and finally a collapse depression formed. Key words: subaqueous Yellow River delta, slide of shallow stratum, collapse depression, wave. Les processus d'instabilite de pente se produisent couramment sur les pentes sous-marines du delta de la riviere Jaune durant les tempetes. Des depressions presque circulaires au haut du front du delta d'une profondeur de 4 a 8 m ont ete observees par releve acoustique, et leurs processus ont ete observes en laboratoire. Cet article analyse les proprietes des profils geomorphiques et acoustiques du haut du front du delta, et compare les proprietes geologiques d'echantillons provenant de zones perturbees et non perturbees. Les resultats demontrent que la masse legere et superficielle peut osciller avec l'action des vagues, et cette oscillation affaiblit le sol environnant en raison du chargement cyclique. La couche est perturbee ou meme detruite selon la profondeur, l'aire de la masse du glissement s'est agrandit graduellement, et finalement une depression par effondrement est formee. Mots-cles : delta sous-marin de la riviere Jaune, glissement de la couche superficielle, depression par effondrement, vague. [Traduit par la Redaction], Introduction The study of seabed slope slides in the subaqueous Mississippi River delta by the United States Geological Survey, along with other departments and colleagues within these departments, began in [...]

China has focused on the development and advancement of its railway system to meet growing demands for services. Reforms began in 1978 and included the building of extensive new lines. Post-1995 plans include accelerated railway network construction, technical renovation projects to speed up road section capacity, improving passenger services, developing rolling stock, and speeding up scientific and technical development. It is hoped foreign investment capital will be attracted.

Regulating the selectivity of CO2 photoreduction is particularly challenging. Herein, we propose ideal models of atomic layers with/without element doping to investigate the effect of doping engineering to tune the selectivity of CO2 photoreduction. Prototypical ZnCo2O4 atomic layers with/without Ni-doping were first synthesized. Density functional theory calculations reveal that introducing Ni atoms creates several new energy levels and increases the density-of-states at the conduction band minimum. Synchrotron radiation photoemission spectroscopy demonstrates that the band structures are suitable for CO2 photoreduction, while the surface photovoltage spectra demonstrate that Ni doping increases the carrier separation efficiency. In situ diffuse reflectance Fourier transform infrared spectra disclose that the CO2·− radical is the main intermediate, while temperature-programed desorption curves reveal that the ZnCo2O4 atomic layers with/without Ni doping favor the respective CO and CH4 desorption. The Ni-doped ZnCo2O4 atomic layers exhibit a 3.5-time higher CO selectivity than the ZnCo2O4 atomic layers. This work establishes a clear correlation between elemental doping and selectivity regulation for CO2 photoreduction, opening new possibilities for tailoring solar-driven photocatalytic behaviors. [ABSTRACT FROM AUTHOR]

Abstract: Lithium-ion batteries with green and inexpensive aqueous electrolytes solve the safety problem associated with conventional lithium-ion batteries that use highly toxic and flammable organic solvents, which usually cause fires and explosions. However, the relatively low capacities (usually<65mAhg−1) and less than 50% capacity retention over 50 cycles unfortunately limit their promising applicability. Herein, a novel model of ordered lamellar organic–inorganic hybrid nanorods is first put forward as an excellent platform to circumvent the above issues. Taking the synthetic highly ordered lamellar V2O3-based hybrid nanorods as an example, they deliver a capacity up to 131mAhg−1, nearly 1.5 and 2 times higher than that of 10-nm V2O3 nanocrystals (90mAhg−1) and 2-μm bulk V2O3 (73.9mAhg−1). Also, their excellent cyclability of 88% after 50 cycles is remarkably better than that of 10-nm V2O3 nanocrystals (64%) and 2-μm bulk V2O3 (41%). This work provides a facile route for gram-scale synthesizing highly ordered lamellar hybrid materials and proves that these unique structures are excellent platforms for significantly improving aqueous lithium-ion battery performances especially at high discharge rates, giving tantalizing perspectives in future design and synthesis of high-performance active materials for aqueous lithium-ion batteries. [Copyright &y& Elsevier]

Plastics take hundreds of years to degrade naturally, while their chemical degradation typically requires high temperature and pressure. Here, we first utilize solar energy to realize the sustainable and efficient plastic-to-syngas conversion with the aid of water at ambient conditions. As an example, the commercial plastic bags could be efficiently photoconverted into renewable syngas by Co-Ga 2 O 3 nanosheets, with hydrogen and carbon monoxide formation rates of 647.8 and 158.3 μmol g -1 h -1 . In situ characterizations and labelling experiments unveil water is photoreduced into hydrogen, while non-recyclable plastics including polyethylene bags, polypropylene boxes and polyethylene terephthalate bottles are photodegraded into carbon dioxide, which is further selectively photoreduced into carbon monoxide. In-depth investigation illustrates that the efficiency of syngas production mainly depends on the carbon dioxide reduction process and hence photocatalysts of high carbon dioxide reduction activity should be designed to promote the efficiency of plastic-to-syngas conversion in the future. The concept for the photoreforming of non-recyclable plastics into renewable syngas helps to eradicate 'white pollution' and alleviate the energy crisis simultaneously., (© The Author(s) 2022. Published by Oxford University Press on behalf of China Science Publishing & Media Ltd.)

The poor conversion efficiency of carbon dioxide photoreduction has hindered the practical application at present, and one of the prime reasons for this obstacle is the inefficient solar energy utilization of photocatalysts. Generally speaking, it is contradictory for a photocatalyst to concurrently possess the broad-spectral response and appropriate band-edge positions for coinstantaneous carbon dioxide reduction and water oxidation. In this Outlook, we summarize a series of strategies for realizing visible-light and IR-light-driven carbon dioxide photoreduction under the guarantee of suitable band-edge positions. In detail, we overview the absorbance of visible light enabled by narrow band gaps in photocatalysts, the extended photoabsorption from UV into the visible light range induced by defect levels and dopant energy levels in photocatalysts, and a more negative conduction band and positive valence band acquired by Z-scheme heterojunctions in photocatalysts. Then, we highlight the expansive photoresponse of IR light caused by intermediate bands in semiconductor photocatalysts and partially occupied bands in conductor photocatalysts. Finally, we end this Outlook concerning more design strategies and application fields of broad-spectral-response photocatalysts., Competing Interests: The authors declare no competing financial interest., (Copyright © 2020 American Chemical Society.)