With the development of blockchain technology and non-fungible token (NFT), digital collections have ushered in a golden age. In the field of cultural and museums, the digital collection has also ...been given a new mission, i.e., to migrate cultural relics from offline places to online digital platforms, thus broadening the application areas and ways of offline collection. However, in the actual implementation, it presents a multifaceted ecology of pros and cons. Beginning from the current situation of displaying and utilizing digital collections, this paper comprehensively discusses the opportunities and risks faced by digital collections in terms of venue breakout, market-based valuation, cultural and tourism integration, illegal finance, digital banditry, and property rights based on the application cases of digital collections in museums, and provides an outlook on the future model of museum digital collection ecology.
•A synergistic effect was found in co-gasification of soda lignin and PE.•The order of gasification efficiency of various plastics: PE > PC ≈ PP > ABS.•Much alkane gases were generated from ...degradation of plastics, especially PE and PP.•The presence of soda lignin promoted the reforming of alkanes and H2 production.
In this study, the co-gasification of soda lignin produced from black liquor and various plastics in supercritical water was investigated experimentally. The effect of the mixing ratio of soda lignin/PE, temperature, reaction time, total concentration and plastic types was studied. A synergetic effect was found in co-gasification of PE and soda lignin, and the maximum influence was obtained at a mixing ratio of 50:50. Increasing the temperature and reaction time, and reducing the concentration improved the gasification efficiency and hydrogen production from co-gasification of PE/soda lignin (50:50). The H2 yield increased over 5 times to 57.0 mol/kg with temperature increasing from 500 °C to 750 °C, and the highest H2 yield of 63.3 mol/kg was obtained at 700 °C when the concentration was reduced to 5 wt%. The gasification efficiencies of different plastics were distinct and the order is: PE > PC ≈ PP > ABS, and the addition of soda lignin improved all the gasification efficiencies. The alkali salts in soda lignin also catalyzed the reforming of CH4 and C2H6 that generated from the depolymerization of plastics, especially PE and PP and improved the hydrogen production.
Let HEI denote the first Loo-keng Hua domain. In this paper, we obtain many elementary results on HEI by the continuous and careful discussions. In some applications, we obtain some necessary ...conditions or sufficient conditions for the boundedness and compactness of the composition operators on weighted Zygmund space defined on HEI.
Continental shale oil is a general term for liquid hydrocarbons and many kinds of organic matter in continental organic-rich shale series with vitrinite reflectance of more than 0.5% at buried depth ...of more than 300 m, and is an important type of source-rock oil and gas. Based on the evolution model of oil generation and expulsion in organic-rich shale series controlled by maturity, continental shale oil is divided into two types: medium-high maturity and medium-low maturity. (1) The continental shale series in China develop high-quality source rocks of freshwater and saltwater lacustrine facies, as well as multiple types of reservoirs, including clastic rocks, carbonate rocks, diamictite, tuff and shale, forming a number of “sweet sections” and “sweet areas” of continuous distribution inside or near source rocks, which have large scale resources. (2) Experimental analysis of organic rich shale samples shows that the shale samples with wavy and horizontal beddings have good storage conditions, and the horizontal permeability of shale is tens to hundreds of times of its vertical permeability, which is conducive to the lateral migration and accumulation of shale oil in the source rocks. (3) After evaluation, the geological resources of medium-high maturity shale oil are about 10 billion tons, which can be effectively developed by horizontal drilling and volumetric fracturing, and will be a practical field of oil exploration in recent years. Shale oil with medium and low maturity has huge resource potential, and technological recoverable resources of (70–90) billion tons, making it a strategic alternative resource of oil industry. However, economic development of this type of shale oil needs in-situ conversion technology breakthroughs. Continental shale oil is an inevitable choice in the process of Chinese continental petroleum exploration from “outside source” to “inside source”. Making breakthroughs in the core technologies such as “sweet area” evaluation and optimization, horizontal well volume fracturing and in-situ conversion technology and equipment is the key to realizing scale development of continental shale oil economically.
The 2+2 cycloaddition is a versatile strategy for the synthesis of strained cyclobutenes of high synthetic value. In this study, two efficient intermolecular 2+2 cycloadditions between two different ...types of chloroalkynes and unactivated alkene are realized with gold catalysis. Of significance is that the reaction works with challenging monosubstituted unactivated alkenes, which is unprecedented in gold catalysis and scarcely documented in other metal-catalyzed/promoted reactions; moreover, the reaction exhibits excellent regioselectivities, which are much better than those reported in literature. With 1,2-disubstituted unactivated alkenes, the reaction is largely stereospecific. The cyclobutene products can be prepared in nearly gram scale and readily undergo further reactions including various cross-coupling reactions using the C(sp2)–Cl and/or C(sp2)–SPh bond, which in turn substantially broaden the scope of accessible cyclobutenes and enhance the synthetic utility of this bimolecular reaction.
A 3D high‐symmetrical pure inorganic material based on a Keggin‐type arsenotungstate, {(H2O)⊂K6(H2O)12}{K6(AsW3VW9VIO40)2} (1), has been hydrothermally synthesized and fully characterized by ...elemental analysis, TGA, IR, UV, and XPS spectrsocopy, and single‐crystal XRD. In compound 1, each three‐electron‐reduced {AsW12O40} polyanion cluster utilizes all of its surface oxygen atoms to connect 12 K1 and 6 K2 cations at its periphery, which can be viewed as µ4‐ and µ2‐bridges to further link with four and two adjacent {AsW12} clusters, respectively. The coordination number and modes of {AsW12} and K+ ions together result in a high‐symmetrical 2,4,18‐connected 3D open skeleton with a new {324·440·54·43·54·42·54·42·54·4·532·633}{34·42}3{3}3 topology. Compound 1 represents the first pure inorganic 3D structure based on the highest connection of Keggin arsenotungstate heteropoly blue and potassium ions. Compound 1 shows efficient photodegradation activity towards MB, MO, RhB, and AP under UV light irradiation. The life of the catalyst, kinetics, and mechanisms of the catalytic reaction have been studied in detail.
A K+ cation as linkage unit has been introduced into the {AsW12} reaction system to build a high‐symmetrical pure inorganic 3D extended framework with a complex topology, which represents the highest‐connected Keggin arsenotungstate heteropoly blue and shows excellent photocatalytic activities for the degradation of typical dyes.
As an important type of “conventional–unconventional orderly accumulation”, shale oil is mature oil stored in organic-rich shales with nano-scale pores. This paper analyzes and summarizes elementary ...petroleum geological issues concerning continental shale oil in China, including sedimentary environment, reservoir space, geochemical features and accumulation mechanism. Mainly deposited in semi-deep to deep lake environment, shale rich in organic matter usually coexists with other lithologies in laminated texture, and micron to nano-scale pores and microfractures serve as primary reservoir space. Favorable shale mainly has type I and IIA kerogens with a Ro of 0.7%–2.0%, TOC more than 2.0%, and effective thickness of over 10 m. The evolution of shale pores and retained accumulation pattern of shale oil are figured out. Reservoir space, brittleness, viscosity, pressure, retained quantity are key parameters in the “core” area evaluation of shale oil. Continuously accumulated in the center of lake basins, continental shale oil resources in China are about 30×108–60×108 t by preliminary prediction. Volume fracturing in horizontal wells, reformation of natural fractures, and man-made reservoir by injecting coarse grains are some of the key technologies for shale oil production. A three step development road for shale oil is put forward, speeding up study on “shale oil prospective area”, stepping up selection of “core areas”, and expanding “test areas”. By learning from marine shale breakthroughs in North America, continental shale oil industrialization is likely to kick off in China.
Based on the investigation of tight oil exploration and development in North America, the successful cases of tight oil exploration and development in North America are summarized. The geological ...differences between continental tight oil in China and marine tight oil in North America is analyzed to explore the technical strategies for the industrial development of continental tight oil in China. The experiences of large-scale exploration and profitable development of tight oil in North America can be taken as references from the following 6 perspectives, namely exploring new profitable strata in mature exploration areas, strengthening the economic evaluation of sweet spots and focusing on the investment for high-profitability sweet spots, optimizing the producing of tight oil reserves by means of repetitive fracturing and 3D fracturing, optimizing drilling and completion technologies to reduce the cost, adopting commodity hedging to ensure the sustainable profit, and strengthening other resources exploration to improve the profit of whole project. In light of the high abundance of tight oil in China, we can draw on successful experience from North America, four suggestions are proposed in sight of the geological setting of China's lacustrine tight oil: (1) Evaluating the potential of tight oil resources and optimizing the strategic area for tight oil exploration; (2) selecting “sweet spot zone” and “sweet spot interval” accurately for precise and high efficient development; (3) adopting advanced tight oil fracturing technology to realize economic development; (4) innovating management system to promote the large-scale profitable development of tight oil.
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