Both developed and developing countries have seen a proliferation of information and communication technologies (ICTs) in recent years. As digital transformation has influenced almost every aspect of everyday life, including interpersonal communication, information seeking and sharing, e-commerce, and entertainment, the dichotomy between online and offline has become less distinct compared to the early years of internet development. These routine practices on the internet, nevertheless, are fundamental to understanding the impact of digital technologies on society. It is, therefore, important for social scientists to theorise and scrutinise how the internet has influenced the routine and mundane lives. To date, social scientists from multiple disciplines, including sociology, political science, communication and information science, have studied how the internet has influenced the society and economy. These include the roles of the internet in establishing and maintaining social networks, mobilising social movements, and revolutionising labour markets. However, little research has addressed the impact of the internet in the everyday lives of its users. In this chapter, I will start with reviewing theoretical frameworks from different fields that focus on the impact of the internet on daily practices, to understand the profound influence of digital technologies in everyday contexts. In particular, I will discuss how the study of everyday life information seeking (information science), domestication theory (communication science), and digital divides (sociology) contribute to the theorisation of daily uses of the internet. I will summarise empirical studies that apply these theoretical frameworks in exploring the adoption and use of ICTs in daily practices. The overview and reflection of theories and empirical studies across different social science fields will provide a comprehensive picture of the role of the internet on everyday lives, as well as point out future directions for the study of the embeddedness of the internet in people’s daily lives.
Abstract Aim Woody and herbaceous habits represent one of the most distinct contrasts among angiosperms, and the proportion of woody species in floras (i.e., “woodiness” hereafter) represents a fundamental structural element of plant diversity. Despite its core influence on ecosystem processes, spatio-temporal patterns in woodiness remain poorly understood. Here, we aim to demonstrate the global spatio-temporal patterns in angiosperm woodiness and their relationship with environmental factors. Location Global. Time period Cenozoic, 66 Ma to present. Major taxa studied Angiosperms. Methods Using newly compiled data on the growth forms and distributions of c. 300,000 angiosperm species and an angiosperm phylogeny, we mapped the current global geographical patterns in angiosperm woodiness, reconstructed ancestral states of growth forms through the angiosperm phylogeny and demonstrated the Cenozoic evolutionary dynamics of woodiness. We evaluated the relationships between woodiness and current climate and palaeoclimate. Results We found that c. 42.7% of angiosperms are woody. Woodiness decreased spatially from the equator towards high latitudes, temporally since the early Cenozoic. Temperature was the best predictor of the spatio-temporal decline in woodiness and was positively correlated with woodiness. Despite the temporal decline in woodiness, macroevolutionary herbaceous-to-woody transitions increased through time and contributed to the evolution of woody floras in temperate drylands, whereas the opposite transitions decreased through time and contributed to herbaceous floras in tropical and subtropical drylands. Main conclusions Our study improves understanding of the spatio-temporal dynamics of angiosperm woodiness. Our findings suggest that temperature is likely to be a determinant of spatio-temporal variations in woodiness, highlighting the role of temperature in maintaining the growth form composition of ecosystems. Our study also calls for attention to growth form transitions (e.g., secondary woodiness) in temperate drylands that have been neglected before.
We construct a model of debt maturity structure and show how a firm trades off between the costs of market liquidity risk and rollover risk. On one hand, the issuance of long-term debt reduces market liquidity because it increases the supply in the secondary debt market, which increases the cost the firm bears for long-term debt (i.e., the cost of market liquidity risk). On the other hand, the use of short-term debt increases the likelihood of early liquidation, which raises the cost of short-term debt for the firm (i.e., the cost of rollover risk). We show that market liquidity risk and rollover risk the firm is exposed to are connected through endogenously determined debt maturity structure. An exogenous shock (e.g., shrinkage of market depth or an increase in risk-free interest rate) that directly increases one type of liquidity risk would induce the firm to alter debt maturity structure and partially offset the impact of the shock by raising its exposure to the other type of risk (i.e., spillover effects exist). We also show that the spillover from market liquidity risk (rollover risk) to rollover risk (market liquidity risk) is more (less) pronounced during economic recessions or in the case of competitive firms.
Field observations of reactive volatile organic compounds (VOCs) were carried out in Kunming, the largest city on the Yunnan-Guizhou Plateau. Proton transfer reaction-time-of-flight mass spectrometry (PTR-TOF-MS) was used to conduct a 40-day online observation. VOCs were characterized, including concentrations, diurnal variations, ozone generation potential, and source apportionment. The results show 18 main observed active VOCs (acetaldehyde, 2-acrolein, acetone, methyl ethyl ketone (MEK), methyl vinyl ketone (MVK), methacrolein (MACR), methyl isobutyl ketone (MIK), 2-pentanone, ethyl acetate, isoprene, α-pinene, benzene, toluene, styrene, C8 aromatic hydrocarbons, C9 aromatic hydrocarbons, 1,3-dichlorobenzene, naphthalene and acetonitrile) with a total concentration of (10.97 ± 5.21) ppb. Eight OVOCs have a total concentration of (7.49 ± 3.10) ppb; two biogenic VOCs (BVOCs) have a total concentration of (1.32 ± 0.79) ppb, and six aromatic hydrocarbons have a total concentration of (1.50 ± 1.14) ppb. The ozone formation potential of isoprene, acetaldehyde and 2-acrolein make up the top three species. The main sources of three OVOC species (acetaldehyde, acetone, and MEK) have local biological sources and primary anthropogenic sources, indicating that the pollution in this area is significantly affected by regional transport. This study can improve our scientific understanding of the composition and sources of VOCs on the Yunnan-Guizhou Plateau and fundamental ozone control in the region.
Abstract Geological CO2 storage is an emerging topic in energy and environmental community, which is, as a commonly accepted sense, considered as the most promising and powerful approach to mitigate the global carbon emissions during the transition to net-zero. Of the geological media which initially considered cover the saline aquifers, oil and gas reservoirs, coal beds, and potentially basalts, up to now only the first two choices have been proven to be the most capable storage sites and successfully implemented at pilot/commercial scales. Here, two tandem papers propose novel strategies for the first time, by synthesizing and utilizing new high-dryness CO2 foam, to enhance geological CO2 storage capacity in saline aquifer and oil and gas reservoirs. In this paper, a new high-dryness CO2 foam is synthesized and injected into the saline aquifers to explore the storage capacity enhancement, with the unique foam-induced advantages of sweep area expansion and storage efficiency improvement. Such a new idea is specifically evaluated and validated through a series of static analytical and dynamic performance experiments. With the optimum surfactant concentration of 0.5 wt%, the foaming volume and quality are determined to be 521 mL and 80.81%, respectively, which also shows excellent salt tolerance with 45,000 ppm Na+, 25,000 ppm Ca2+, and 25,000 ppm Mg2+. Moreover, the water consumption for CO2 storage decreases from 464.31 g/mol at 25% foam quality to 67.38 g/mol at 85% foam quality by using the new CO2 foam. Overall, the newly synthesized CO2 foam could effectively enhance geological CO2 storage capacity and concurrently diminish water consumption, therefore realizing the win-win environment and economic benefits.
Fine-grained pyrites are difficult to be denitrified under natural environment due to chemical oxidation with O2. In this study, the pyrite/PHBV composites were synthesized through high-temperature melting and realized nitrogen and phosphate removal under natural aerobic conditions. Results showed that pyrite/PHBV-40 composites had the highest denitrification rate of 0.61 mg NO3–N /(LCh) with low SO42-production, and its removal efficiency of nitrogen and phosphorus was 98% and 41%, respectively. Microbial community structure analysis revealed that the enrich sulfate-reducing bacteria (SRB) on the pyrite/PHBV-40 composites demonstrated that the sulfate reduction driven by SRB enhanced denitrification process, and thereby the S cycle could underpin the potential self-sustainability of pyrite/PHBV-40 composites. Co-occurrence network analysis showed that Fe oxidizers/reducers (e.g., Ferruginibacter/Geobacter) and SRB (e.g., Desulfovibrio) were the keystone species in microbial community. Bugbase analysis showed that formed biofilms mainly consisted of aerobic and facultative anaerobic strains, which was corresponding to structure of biofilm including aerobic and anoxic layer. Partial mantel test revealed the total Fe and nutrients (e.g., N and P) are the drivers in OTU and phenotype composition, respectively. Metabolic pathway analysis suggested that pyrite/PHBV composites may not only accelerate glycolysis with rapid hydrolysis of PHBV, but also enhance the TCA cycle with high production of ATP and NADH. The final product of nitrate reduction is N2O or NO, and the cysJ gene play an important role in sulfate reduction in pyrite/PHBV systems. Overall, the novel synthesized pyrite/PHBV composites are an ideal functional material with high denitrification rate, no secondary pollution and long service life. Our study highlights pyrite/PHBV-induced strength in microbiota dynamics and C, N, S transformation, therein, the sulfate reduction process cannot be overlooked.
Ultrasonics could be a promising technology to modify the geological formations for geo-energy productions, carbon geological sequestrations, monitoring of crack formation with stress and volcanic activity prediction. However, immature understanding of the post-ultrasonic geological formations seriously restricts the further applications in practices. This paper initially focuses on the in-situ geological porous media of low-permeability sandstones, analysing their stress sensitivity and relevant influential factors post-ultrasonics. Basically, the original and treated in-situ cores with and without ultrasonics were characterized through a series of experimental approaches, including permeability stress sensitivity (PSS), high-pressure mercury intrusion (HPMI), inline nuclear magnetic resonance (NMR), X-ray diffraction tests (XRD), triaxial stress test (TS) and scanning electron microscope (SEM) to explore the stress-induced rock compression mechanisms and the associated effects of pore restructures and mineral re-compositions. The experimental results reveal that the ultrasonics cause desorption of clay minerals at relatively low pressures (<5 MPa), which enlarges the pore throat and increases the permeability by 2.4 times. As the pressure increasing to 5 MPa, the porosity decreases from 8.79% to 6.13% because the plastic deformations of rock become irreversible without the cementing support (i.e., clay minerals). A further pressure increases from 5 to 25 MPa results in more porosity reduction from 6.13% to 5.77% through the rigid compressions. Overall, under the same pore pressure, the core porosity with ultrasonic treatments is usually smaller than the original ones, which thus indicates ultrasonics to some extent augment the stress sensitivity of core with compression. Hence, it is suggested to control pore pressure if the ultrasonics are introduced for geo-energy productions and carbon geological sequestrations.
Concurrently elevating the degradation efficiency of pollutants and realizing the reduction of iron sludge in Fe-based catalytic ozonation is important but still challenging. Herein, we developed an electrocatalytic ozonation (ECO) system with iron plate cathode and graphite felt anode (ECO-Fe-cathode), which was free from added chemical reagents. Unlike the iron plate as a sacrificial anode in the ECO (ECO-Fe-anode) system, this delicately designed system shows a much higher degradation rate of ibuprofen (kobs = 1.490 min−1) than that of the ECO-Fe-anode system (kobs = 0.345 min−1). Simultaneously, the effluent was totally limpid without the corrosion of iron plates and the formation of iron sludge in the ECO-Fe-cathode system. Unexpectedly, the generation of singlet oxygen (1O2) which is indirectly generated by the single-electron transfer derived from superoxide ion (O2•-) is the primary reactive oxygen species (ROS) in the ECO-Fe-cathode system, which is different from the ECO-Fe-anode system with hydroxyl radicals (•OH). Moreover, linear sweep voltammetry (LSV) was applied to reveal the oxygen evolution reaction (OER) performance of the iron plate and graphite felt, and the results showed that graphite felt as anode has better electrocatalytic performance. The electrochemical analysis and density functional theory (DFT) calculation revealed that ozone adsorbed on the iron plate surface is more conducive to facilitating and triggering subsequent reactions. Finally, the different degradation pathways of ibuprofen in both systems were proposed. This work represents a fundamental breakthrough toward the design of an efficient and harmless ECO system for wastewater treatment.
Rationally regulating reaction mechanisms in Fenton-like reactions by tuning the properties of catalysts is of great significance, but still challenging. Herein, we synthesized various active center size-dependent catalysts to realize the switching of reaction mechanisms and pollutant degradation routes in peroxymonosulfate (PMS) activation systems. The results illustrated that the reaction mechanism transformed from radical oxidation (51.64%) to nonradical oxidation (89.92%) with the decrease of active center size from nanoparticle (CoNP-NC) to single atom (CoSA-NC). The evolution of reactive species switched the degradation intermediates and pathway of sulfisoxazole (SIZ). The generation of singlet oxygen (1O2) in CoSA-NC/PMS tends to selectively attack electron-rich site of SIZ, while reaction between radicals and SIZ prefers non-selective oxidation in CoNP-NC/PMS system. Besides, the toxicity tests indicated that the conversion from non-selective to selective oxidation resulted in lower toxicity of effluent after reaction, which can further reduce environmental risks of effluent.
Abstract Complementary metal-oxide-semiconductor (CMOS) field-effect transistors (FETs) are the key component of a chip. Bulk indium arsenide (InAs) owns nearly 30 times higher electron mobility µe than silicon but suffers from a much lower hole mobility µh (µe/µh = 80), thus unsuited to CMOS application with a single material. Through the accurate ab initio quantum-transport simulations, the performance gap between the NMOS and PMOS is significantly narrowed is predicted and even vanished in the sub-2-nm-diameter gate-all-around (GAA) InAs nanowires (NW) FETs because the inversion of the light and heavy hole bands occurs when the diameter is shorter than 3 nm. It is further proposed several feasible strategies for further improving the performance symmetry in the GAA InAs NWFETs. Short-channel effects are effectively depressed in the symmetric n- and p-type GAA InAs NWFETs till the gate length is scaled down to 2 nm according to the standards of the International Technology Roadmap for Semiconductors. Therefore, the ultrasmall GAA InAs NWFETs possess tremendous prospects in CMOS integrated circuits.