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To investigate the influence of temperature and humidity variations on creep in high-performance concrete beams, beam tests were conducted in both natural and laboratory settings. The findings indicate that the variations in creep primarily stem from temperature changes, whereas humidity changes have little influence on fluctuations in both basic creep and total creep. The influence of humidity on creep is more strongly reflected in the magnitude of creep. Functions describing the influence of temperature and humidity on the creep behavior of high-performance concrete (HPC) subjected to fluctuating conditions are proposed. The findings were employed to examine creep deformation in engineering applications across four places. This study complements the correction method for the creep of members under fluctuating temperature and humidity. This research application can provide a basis for the calculation of the long-term deformation of HPC structures in natural environments. [ABSTRACT FROM AUTHOR]

As in many cities, utilitarian cycling is part of Toronto's climate strategy. For this tactic to work, cycling must occur throughout the city, yet despite most of the city's suitable short trips (60%) occurring in the suburbs, suburban residents cycle far less for transport than downtown residents where most cycling infrastructure is found. Nonetheless, some people in suburban areas cycle for transport, but little research focuses on suburban cycling. This has important implications for health, climate and equity. We used generalized structural equation modeling to analyze data from a survey of factors influencing utilitarian and recreational cycling among residents of a lower-income auto-oriented suburb lacking utilitarian cycling infrastructure (n = 215). Principal component analysis was used to develop latent attitudinal variables. The strongest predictors of utilitarian cycling were the frequency of recreational cycling, bike ownership, knowing people who bike, being male, and owning fewer cars. The strongest predictors of recreational cycling were bicycle ownership, knowing people who bike, knowing where to access repairs, and having attitudes strongly related to health and safety. Utilitarian cycling did not influence the frequency of recreational cycling. None of the latent attitudinal variables influenced utilitarian cycling. However, respondents scoring high in the expense and theft variable were more likely to live in lower income households. Those in higher income households scored higher on the health and safety variable. Results suggest group rides, access to bicycles and repairs, and ways to meet people who bike may be useful interventions to increase utilitarian cycling in suburban communities. [ABSTRACT FROM AUTHOR]

This work studies the creep characteristics of concrete sustaining initial damage by considering both the initial damage to concrete and the damage caused by crack growth in the creep process. The damage state of concrete is characterized by the characteristics of the amplitude of ultrasonic waves. Creep tests on concrete prisms with different degrees of initial damage were carried out at loads of 40%, 50%, and 60% compressive strength. The results show that the initial damage to concrete significantly impacts its creep behavior. The modified creep curve of concrete, including the initial damage variable, is consistent with the creep curve of undamaged concrete at different stress levels, proving the applicability of the damage variable. [ABSTRACT FROM AUTHOR]

• Millennials make their mode choices of shopping travel based on built-environment, socio-economic status, and preferences. • Completed shopping facilities around neighborhoods encourage active modes. • Millennials with different life stages and shopping habits have differentiated preferences on mode choice. • To encourage non-motorized travel modes, neighborhood design should consider socio-economic attributes of its residents. China's cities have witnessed rapid growth of the consumption economy in recent years. The millennials (defined in this study as those born between 1980 and 2000, also known as Generation Y) have become one of the main forces of domestic consumption. Thus, shopping trips of millennials significantly influence the transportation sector in the context of the consumption society. Previous studies intensively investigated the determinants of non-work travel. However, only a few empirical analyses were conducted on the shopping travel behavior of millennials in China's cities. In addition, few studies integrated the influence of life stages and shopping habits in their analysis of travel behavior. The purpose of the study is to fill these research gaps by taking Beijing as a case. By using travel survey data in Beijing, this study explores the characteristics and determinants of shopping travel by millennials. A multinomial logistic (MNL) model is applied to investigate the travel mode choice of millennials for shopping purposes. A latent class (LC) model is used to further specify segment preferences according to individual life stages and shopping habits. The impacts of several major factors are addressed. These factors include neighborhood built environments, individual subjective attitudes toward travel, and household attributes. Results show that the completed commercial facilities and public transportation connections surrounding the neighborhoods would encourage shopping by walking or cycling. The findings and conclusions could enhance the knowledge of millennials' travel behavior and contribute to policy-making to encourage sustainable transport by integrating land use and transportation planning strategies. [ABSTRACT FROM AUTHOR]

Wet flue gas desulfurization (WFGD) wastewater treatments used by most coal-fired power plants have difficulty in realizing completely zero emission. An atomizing and crystallization treatment of desulfurization wastewater using high-temperature gas from SCR (selective catalytic reduction) denitrification reactors was proposed. Using ANSYS software, 3D modeling of a crystallization tower and a numerical simulation of evaporation were conducted, and the crystallization process of wastewater droplets was studied. Based on the results of the simulation, effects of four main factors on evaporation efficiency were analyzed. The results indicate that droplet group with the same initial diameter of 10 μm can evaporate entirely within a time of 0.6 s and a height of 2.4 m when the mass flow rate of 620 K flue gas increases to 2.1 kg/s. In a practical process, fluctuations in the temperature and humidity should be avoided to guarantee complete evaporation. The results provide data support for technology design of crystallization towers applied in power plants. [ABSTRACT FROM AUTHOR]

Summary: Both cool roof and phase change thermal storage are promising technologies in decreasing building energy consumption. Combining these two technologies is likely to further enhance the thermal comfort of the building as well as reduce air condition loads. In this paper, the cooling performance and energy‐saving effects of four types of roof (normal roof, phase change material [PCM] roof, cool roof, and cool PCM roof [cool roof coupled with PCM]) were investigated under a simulated sunlight. Experimental results indicate that compared with normal roof, the other three roofs are able to narrow the indoor temperature fluctuation and decrease the heat flow entering into the room. Among them, cool PCM roof gave the best energy‐saving effect that can lower the indoor temperature and heat entering into rooms by 6.6°C and 52.9%, respectively. Besides, the PCM location, PCM thickness, and insulation thickness exerted great impacts on the cooling performance of the roof. Placing the PCM on the internal layer beneath the extruded polystyrene (XPS) insulation board can make the indoor temperature 1.2°C lower than that on the middle layer. Although thicker PCM panels or insulation boards can provide a better thermal insulation, 5 mm in PCM thickness and 20 mm in insulation thickness are enough to guarantee the indoor temperature of cool PCM roof system at a comfortable range (22°C‐28°C) for a whole day. These findings will give guidance in designing buildings with a light and compact roof structure to decrease energy consumption and improve comfort level. [ABSTRACT FROM AUTHOR]

Abstract Transit pricing is one of the major factors influencing transport-related equity. In particular, in developing countries with low car-dependency rates, public transit plays an important role in providing access for disadvantaged groups to desired destinations, such as jobs, education, and health care. Changes in public transit fares can significantly affect residents' travel expenditures and possibly transport-related social equity. However, cases from developed countries dominate the existing literature in the field, and the comparison of equity between flat fare and distance-based fare is scarce. This study aims to fill this gap by examining the case of Beijing. To relieve operators' financial pressures, the Beijing municipal government replaced its flat metro fare (CNY 2) by a distance-based fare in 2014. Using retrospective survey data, this study analysed the effects of the metro fare increase on transport equity. An index of affordability was established to measure transit equity, and the multivariable models showed that the introduction of a distance-based fare would significantly increase the cost burden of vulnerable residents on metro use with such groups as low-income earners and young workers, who pay more than their counterparts. Because of the unaffordable housing price in Beijing and the different patterns of residence by income, this study also investigated the interaction effects of housing tenure and residential location. The compelling results suggest that residents who owned housing in the suburbs experienced less increase of the transit burden. These findings are interpreted as supporting the construction of affordable housing in suburban areas and integrated transit-oriented as tools to enhance social equity under the circumstance of property-led urban growth. Highlights • An index of transit affordability was used to measure transit equity. • Distance-based fare adversely influences low income earners and young people. • Car ownership plays a limited role in reducing transit costs of the poor. • The construction of affordable housing in suburbs could enhance transit equity. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Thin polyacrylonitrile-based (PAN-based) carbon fiber felt as a porous medium structure for loop heat pipe is proposed firstly as its potential capillary and it is in favor of miniaturization of LHP. • Carbon fiber is processed by copper chemical-plating modification on its surface for promotion of its wettability, which means the wick becomes hydrophilic from a hydrophobic material. • The plating layer is closely bonded with fiber but not reduce the bore diameter and the potential porous structure is not changed after copper plating. • The IR camera and the electronic balance are used to qualify its capillary pressure, which meets the requirement as a capillary wick. • The LHP with carbon fiber capillary wicks starts and operates successfully and the risk of temperature fluctuation is decreased during the operation. Abstract This paper reports on the working characteristics of a flat plate loop heat pipe (LHP) with a thin polyacrylonitrile-based carbon fiber felt as a porous medium structure. To improve the hydrophilic properties of carbon fiber, a chemical-plating process is used to coat the carbon fiber surface with copper. The surface characteristics and pumping characteristics of modified capillary wicks are characterized using an electron microscope, scanning electron microscope, infrared radiation camera, and high-speed photography. The results show that the flat plate LHP with the modified thin carbon fiber felt as the capillary wick can start successfully and maintain stable operation in the range of 15–75 W (heat flux of 12 W/cm2). The total thermal resistance varies from 1.1 to 0.45 °C/W at heat loads ranging from 15 to 75 W. As a flexible and soft material, carbon fiber has the advantages of good matching with the evaporator, and resistance to mechanical damage. After it is modified by copper plating on its surface, it becomes a kind of hydrophilic material with an excellent capillary force. Furthermore, the copper plating layer increases the surface thermal conductivity and is beneficial to the uniform heating of the working fluid in the evaporating chamber. The fabrication of carbon fiber capillary wick is not limited to its volume. [ABSTRACT FROM AUTHOR]

Abstract The determinants of car use and car ownership are heatedly discussed in transportation planning research. However, little is known about the effects of life-course events, for instance, residential relocation and changes in household structure, on driving behaviour. In particular, in China's cities, massive urban renewal and residential relocation provide new contexts for transport. This paper aims to contribute to new evidences for the links between changes in car use and residential relocation by taking Beijing as a case. Structural Equation Modelling is applied to explore the effects of built environment, self-selection, and household status on car ownership and car use, and to highlight the mediating effect of changes in commuting distance on travel mode variation following residential relocation. The results show that residents make their travel choices based on their life stages, that is, the birth of kids, marriage, and a larger household size encourage car purchase and facilitate car use. The built environment variables play moderate roles in reshaping driving behaviour after residential relocation when controlling for other factors. Besides, commuting distance has marginal effects on car use and travel mode choice. More specifically, increasing commuting distance encourages the use of the metro and private cars. The present study has important implications for future research and policies aiming to discourage car dependence in growing metropolises. Highlights • Residents make their travel choices based on their life stages • A larger household size encourage car purchase and facilitate car use. • The built environment variables play moderate roles in reshaping driving behaviour after residential relocation. • Increasing commuting distance encourages the use of the metro and private cars. [ABSTRACT FROM AUTHOR]

A multifunctional theranostic nanoplatform based on nanosized graphene oxide (GO) and MnWO 4 has been developed by in situ growth of MnWO 4 nanoparticles onto GO surfaces in a hyperthermia polyol medium containing polyethylene glycol (PEG). In comparison with GO and MnWO 4 /PEG, the near infrared (NIR) absorbance of the produced GO/MnWO 4 /PEG nanocomposite is significantly improved, resulting in an enhanced photothermal conversion capability and a good photoacoustic (PA) imaging performance. It is worth to note that the longitudinal relaxivity r 1 of GO/MnWO 4 /PEG reaches impressively 11.34 mM −1  s −1 in a 0.5 T magnetic field, which is significantly higher than ordinary Mn(II)-based T 1 agents. In vivo magnetic resonance and PA imaging demonstrate that GO/MnWO 4 /PEG could serve as an efficient bimodal contrast agent to guide the cancer treatment. GO/MnWO 4 /PEG shows a high loading capacity for anticancer drug doxorubicin hydrochloride (DOX) by noncovalent forces, and the drug release could be triggered by lower pH value and external NIR light. Effective synergistic photothermo-chemotherapy has been performed in xenograft 4T1 tumor models after intravenous administration of GO/MnWO 4 /PEG/DOX. No obvious toxicity and side effect have been observed during in vivo treatment. These positive results suggest the promising application of GO/MnWO 4 /PEG as a versatile nanoplatform for multimodal imaging-guided cancer synergistic therapy. [ABSTRACT FROM AUTHOR]

• The present study conducted a 710-day creep experiment on high-performance concrete with a loading period of 45–260 days. • The influence function of loading ages on creep of ordinary portland concrete and high-performance concrete were developed respectively. • Compares the experimental results on the creep law of high-performance concrete with the results of codes calculations. • Mechanism how admixtures impact the influence regulation of loading ages on creep is explained. The present experimental and analytical study conducted a 710-day creep experiment on high-performance concrete(HPC) with a loading period of 45–260 days. The effects of the loading period on the shrinkage, elastic modulus, and creep of HPC, as well as the deviation from the prediction results of the ordinary concrete model, were examined. The results show that admixtures delay the hydration and hardening process of HPC compared with ordinary concrete. The influence of the loading period on the creep of the aged HPC is mainly reflected in the first day of creep development. The creep of concrete declines with the loading age following a hyperbolic function, f C (τ), so a creep model based on f C (τ) is established and validated by the test results. Moreover, we take f ψ ́(τ) to characterize the influence coefficient of the loading period for the creep coefficient. f ψ ́(τ) is first proposed based on the literature on the experiments with ordinary concrete with a loading age in the range of 1–5000 days and then modified based on the experimental results to predict the creep of HPC. Finally, the broad applicability of f ψ ́(τ) was confirmed by applying it to six studies. The present study can provide a basis for establishing the creep model for high-performance concrete. [ABSTRACT FROM AUTHOR]

Industrial applications using recycled fibres or resins are still rare due to inferior performance to cost ratio. In most cases, glass fibre reinforced polymer (GFRP) materials with thermoset matrices are considered unsuitable for reprocessing and reuse as a valuable reinforcement of composites. In this work, mechanical frictional grinding is utilized to recover the reinforcement fibres, which are still partially coated with the used epoxy resin. For the first time, the possibility and valorization potential of incorporating all the recycled GFRP waste into a Fe-rich silicate slag, a byproduct of non-ferrous metallurgy production, is evaluated. The results show that this double-recycling route does not only allow for a much greater level of GFRP waste incorporation (20 wt%) in the inorganic matrix but also achieves remarkable flexural strength enhancement (79%) when compared with other results from the literature on fiber-reinforced cementitious materials. • Frictional grinding was used to recycled the glass fibre thermoset composite. • All waste (with resin) was for the first time used into a Fe-rich inorganic polymer. • The recyclates notably increase inorganic polymer's flexural strength (up to 79%). • The resin residues play a dual-role in the system. • This study provides a promising and green solution for glass fibre thermoset waste. [ABSTRACT FROM AUTHOR]

l A flat loop heat pipe with carbon fiber wick as well as visible evaporator and condenser was designed and observed. l The start-up characteristics were studied by directly observing and temperature recording at the same time. l Various operate conditions such as different heating powers, filling ratios, tilt angles and working fluid materials were applied on LHP. A flat loop heat pipe (LHP) with visible evaporator and condenser was designed and observed during the start-up stages. A novel porous material, the carbon fiber felt, was used as the capillary wick. To enhance the heat conduction and the flow fluency, the wick was modified into comb shape and pin fins were fabricated in the evaporator. To directly observe the flow and the boiling condition inside LHP, silica glasses were fixed on the evaporator and condenser. During the slow evaporation stage, small working fluid droplets condensed on the inner surface of the silica glass and no boiling phenomenon can be observed inside the evaporator. During the boiling appearance stage, large amount of vapor generated in the evaporator chamber. Under different operating conditions, temperatures at six measure points were monitored and recorded. When the heating power changed from 30 W to 200 W, the stable temperature of the heating sheet linearly increased from 55.57 °C to 111.9 °C. A large filling ratio always results in a long start-up process and a large temperature fluctuation. Among LHP with three different working fluids, LHP with acetone-ethanol mixture has the quickest start-up, and LHP with the pure acetone has the lowest stable temperature. [ABSTRACT FROM AUTHOR]

• A new algorithm was proposed and applied to numerical simulations of the flow properties in the fibrous porous media. • Experiments of permeability measurements were conducted on carbon fiber felts with different porosities. • Comparison of the simulation results with plenty of correlations showed that the new method is convenient and accurate. • Lattice Boltzmann method was used based on its advantage in the simulations with narrow geometries. Three flow types and previous modeling methods for the fibrous porous media (FPM) are summarized. A novel algorithm for modeling FPM structures was proposed to overcome shortcomings of other modeling methods. Carbon fiber felts were observed by a scanning electron microscopy to obtain geometrical information. Lattice Boltzmann method (LBM) was used in simulations for predicting flow properties. Permeability measurements and other correlations validated the new simulation method. Compared with other two common algorithms, the new algorithm predicted the flow properties in FPM more precisely. Results indicate that tortuosity in FPM increases as the porosity decreases, and the general range of the tortuosity is larger than that in the granular porous media. The effect of fiber diameter on the dimensionless permeability and the tortuosity is less than that of the porosity. A slight decline in dimensionless permeability was observed as the fiber diameter increases from 0.5 to 300 µm. [ABSTRACT FROM AUTHOR]

Subterranean estuaries, the mixing zone between terrestrial groundwater and coastal seawater, are important biogeochemical hotspots. In the present study, organic carbon cycling and related drivers, including the characterization of different organic carbon pools and sediment microbial community, were investigated in a subterranean estuary seepage face. Within the first 20 cm depth seepage face sediments, both production and removal of dissolved organic carbon (DOC) were observed, mainly driven by heterotrophic microbes. From spring to autumn, active DOC production occurred on the seepage face at the 15–20 cm depth, likely via aerobic degradation of sediment organic carbon (SOC) with subsequent release of dissolved fractions into the porewater. During winter, DOC production moved to a shallower depth of the seepage face due to increasing SOC content in the surface layer. DOC production rate depended on heterotrophic microbial biomass (e.g. Proteobacteria) and was enhanced by high microbial activity and porewater advection. DOC removal frequently occurred at the 0–5 cm depth layer except in winter. The seasonal shift in carbon source utilization (SOC to DOC) in this layer likely resulted from the decrease in SOC pool, especially the labile portion of SOC and the increased availability of DOC due to production in the deeper sediment (15–20 cm). Given the similarity in microbial community structure along the sediment profile, this shift suggests SOC as the preferential carbon source for benthic microbes as well as adaptive flexibility in microbial carbon source utilization. DOC removal was also significantly tied to microbial activity and advection rate. Because DOC production rates were higher compared to DOC consumption the seepage face acted as a net source of DOC to the coastal ecosystem. Unlabelled Image • Production and removal of DOC in a seepage face in the Sanggou Bay were obtained. • DOC production was mainly driven by decomposition of SOC via heterotrophic microbes. • DOC removal was found in the surface layer, mainly linked to biological assimilation. • Changes of sediment microbial community structure may influence DOC turnover rates. • Porewater temperature and flow rates also impacted DOC reaction rates. [ABSTRACT FROM AUTHOR]

• Two inorganic composite phase change materials were introduced into the floor system. • A double-layer radiant floor system with two phase change layers was constructed. • The two composites based on expanded graphite exhibited different melting points. • The performance of test rooms with different systems in winter or summer was studied. • Two composites endow the test room better thermal comfort and lower power costs. Double-layer radiant floor systems that consist of two inorganic phase change layers placed at different positions, were first explored for regulating the indoor thermal comfort in winter and summer climates. Specifically, two hydrated salts having different melting points were respectively compounded with expanded graphite to obtain enhanced thermal conductivity. In the floor systems, Na 2 HPO 4 •12H 2 O-based composite (31.3°C) and CaCl 2 •6H 2 O-based composite (20.2°C) were used for the heat storage layer and the cold storage layer, respectively. It is found, in the winter climate, the room equipped with a radiant floor system consisting of an upper heat storage layer and a lower cold storage layer, realizes a thermal comfort duration of 2.2 times that of the reference room containing pebbles in the floor. Significantly, the radiant floor system constructed by just exchanging the positions of the two layers endows the room with a thermal comfort duration of 8.1 h in the summer climate, which is 1.7 times that of the reference room. Moreover, appropriately enhancing the thermal conductivity of the composites can promote energy savings by reducing the operating time of the active system. It is estimated that the double-layer radiant floor systems can save economic costs by shifting the peak load. Image, graphical abstract [ABSTRACT FROM AUTHOR]

In this paper, a loop heat pipe (LHP) with a carbon fiber capillary wick was taken as the research object to study the steady state inside the LHP and validate the effectiveness of proposed improvements through CFD numerical simulations. A 3D model of the LHP was built and numerical simulations of steady state operation were conducted by ANSYS software. Through comparison of experiment and simulation results, heat leakage from the heated surface to the compensation chamber (CC) was identified as the major cause of failure in the feasibility experiment. The addition of a heat insulation layer on the contact surface between shells of the evaporator and the compensator was validated as an improvement in reducing heat leaking through the metal shells. The substitute of the copper plating by an alumina-copper coating on surface of the carbon fiber capillary wick was proposed as an improvement to decrease the heat transferring through the capillary wick. The simulation shows that a silicon sheet with low thermal conductivity can increase the liquid volume fraction in the CC to 23%, while an yttria-stabilized zirconia (YSZ) heat insulation layer can raise the figure to 74%. According to simulation results, the combination of YSZ layer and alumina-copper coating can realize a temperature drop of 5.7 K comparing with the combination of silicon sheet and copper plating. The optimized experiment indicates that the use of the heat insulation layers improves stability of operation and increases bearing heat load of the LHP. The dependability of simulation results and the rationality of experimental error were proved by comparing results of experiment and simulation under the same operation conditions. • Heat leakage form shells and capillary wick causes the failure of startup and operation. • Silicon sheet is effective on reducing heat leakage as heat insulation material. • YSZ coating can obstruct most of the heat leakage, which makes it more effective than the silicon sheet. • Alumina-copper coating is an ideal substitute of copper plating of carbon fiber capillary wick. [ABSTRACT FROM AUTHOR]

• Prepares CPCM with g-C 3 N 4 as a novel porous matrix to composite with Mg(NO 3) 2 ·6H 2 O. • G-C 3 N 4 prevents liquid leakage and fully resolves the subcooling of Mg(NO 3) 2 ·6H 2 O. • Sealants covering the surface of the CPCM prevents dehydration of hydrated salt. • The coated CPCM have stable phase change characteristics after thermal cycling. Mg(NO 3) 2 ·6H 2 O is a promising thermal energy storage material owing to its suitable melting point and high latent heat; however, it suffers from poor thermal stability owing to dehydration. This paper presents a two-step encapsulation method to prepare a shape-stabilized Mg(NO 3) 2 ·6H 2 O composite phase change material (CPCM). First, Mg(NO 3) 2 ·6H 2 O is infiltrated into a novel porous matrix – the graphitic carbon nitride (g-C 3 N 4). The g-C 3 N 4 provides a microhousing for Mg(NO 3) 2 ·6H 2 O to prevent liquid from leaking out during the solid–liquid phase change. The g-C 3 N 4 also significantly reduces the sub-cooling degree of Mg(NO 3) 2 ·6H 2 O from 29.2 °C to 1.9 °C. The Mg(NO 3) 2 ·6H 2 O/g-C 3 N 4 composite with 80 wt% Mg(NO 3) 2 ·6H 2 O has a phase change temperature of 87.0 °C and a specific phase change enthalpy of 112.30 kJ kg−1. Second, the Mg(NO 3) 2 ·6H 2 O/g-C 3 N 4 composite is shaped into a cylinder and then macroencapsulated with commercial adhesive sealants (an epoxy resin structural adhesive and silicon sealant). The sealants provide a shell for the hydrated salt to prevent dehydration. After 100 thermal cycles, the composite phase change material only lost 0.84% and 6.25% in weight with coatings of epoxy resin and silicon sealant, respectively, which are much lower than the 22.92% for the uncoated composite phase change material. The specific phase change enthalpy of the composite phase change material barely changed after 100 cycles; however, the loss for the uncoated composite phase change material reached 22.47%. The joint effect of the g-C 3 N 4 matrix and the sealants improve the thermal stability and reliability of the Mg(NO 3) 2 ·6H 2 O. This sequential multi-scale encapsulation method is promising for solving the typical problems of hydrated salts. [ABSTRACT FROM AUTHOR]

The last mile between metro stations and commuters' homes or workplaces has become one of key topics in relation to metro ridership in megacities where more than 10 million people live. Although the public bicycle is widely believed to be one of new ways to solve the last-mile problem, the determinants of the use of public bicycles by commuters as a feeder mode have been scarcely discussed in the literature. This paper aims to contribute to this topic by using Beijing as a case study. Based on a travel survey among public bike users in Beijing, this study applied the binary logit model and cluster analysis to explore the determinants of public bike use around metro stations. The paper focused on three independent variables: route environment, socioeconomic factors, and travel distance. The results showed that middle-aged and medium-income commuters are more likely to use public bicycles as a feeder mode for metro transport. The built environment had significant effects on public bike use. Most of the cyclists preferred cycling routes with high directness, while high-income and high-education cyclists viewed comfort and safety of the trip as priority factors. Most trips were within 2 km, and a longer travel distance was significantly related to a higher possibility of public bicycle use. The findings and conclusions can enhance our existing understanding of public bike use as a feeder mode to solve the last mile problem and provide new evidence for policymaking on promoting public bikes in megacities. [ABSTRACT FROM AUTHOR]

In this paper, firstly, we introduced a second order non-linear recursive sequence, then we use this sequence and the combinatorial methods to perform a deep study on the computational problem concerning one kind sums, which includes the Chebyshev polynomials. This makes it possible to simplify a class of complex computations involving the second type Chebyshev polynomials into a very simple problem. Finally, we give a new and interesting identity for it. [ABSTRACT FROM AUTHOR]

• A solar water heating system using a new type of collector was designed. • SAT/GO/EG functioned as both solar-absorbing substance and thermal storage medium. • The solar-absorbing efficiency of SAT/GO/EG was as high as 63.7%. • The solar-to-thermal conversion efficiency of novel system was equal to 54.5%. Solar energy has been widely used in water heating systems. Latent thermal storage technology using phase change material (PCM) has also attracted great attention in energy storage field. In this study, two kinds of composite PCM- sodium acetate trihydrate/expanded graphite (SAT/EG) and sodium acetate trihydrate/graphene oxide/expanded graphite (SAT/GO/EG) were prepared using a physical hybrid method. The melting temperature and latent heat of SAT/EG were 57.9 °C and 218.1 J/g, respectively. GO showed a negligible influence on the thermal thermophysical characteristics of composite PCM. Exposed in solar radiation, two PCMs can experience phase change almost at same rate. The leakage tests were conducted on these PCMs with the purpose of confirming the density of PCMs. The highest densities at which the PCMs can keep good shape stabilities were 0.8 g/cm3 for SAT/EG and 1.0 g/cm3 for SAT/GO/EG, which indicates that traces of GO (less than 0.1 wt%) can improve the shape stability of compressed PCMs. A solar water heating system equipped with a new type of collector was constructed by employing SAT/GO/EG (1.0 g/cm3, 1628 g) as the solar-absorbing substance and thermal storage medium simultaneously. Under real solar radiation, the SAT/GO/EG can finish phase change and reach the temperature above 70 °C from 9:00 AM to 2:00 PM on a typical day in Zhuhai, China. The solar-to-thermal conversion efficiency of the system was calculated to be 54.5%. These results illustrate that SAT/GO/EG possesses excellent solar-absorbing performance and shows great promise in designing novel solar water heating system. [ABSTRACT FROM AUTHOR]

Cobalt phosphide (CoP) is a promising electrocatalyst due to its abundance and excellent stability in alkaline solution. However, its poor conductivity and intrinsic catalytic activity limit its potential in electrochemical water splitting. To address this, a heterogeneous atom doping strategy has been proposed to synthesize magnesium-doped cobalt phosphide nanoneedle arrays, or Mg-doped CoP. Our theoretical calculations show that transition metal Mg atoms doping into the CoP lattice can enhance the electronic structure and modulate the free energy of reacting species, resulting in a significant improvement in the intrinsic catalytic activities for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) process. The electrochemical tests reveal that the optimal 10% Mg-doped CoP nanoneedle arrays exhibit outstanding HER and OER electrocatalytic activities with overpotential values of 85 and 236 mV at 10 mA/cm2, respectively, outperforming previously reported CoP-based catalysts. This study not only presents a strategy to enhance the catalytic activity of CoP-based materials, but also offers a reference for achieving efficient electrochemical hydrogen production by hydrolysis. [Display omitted] • The charge compensation effect optimizes not only the electronic structure but also the free energy of H∗ and HOO∗ species. • The low-valent Mg2+ ions replace part of the Co3+ sites in the CoP lattice. • The creation of phosphorus vacancies in adjacent sites to maintain electroneutrality. [ABSTRACT FROM AUTHOR]

Wind turbines are important for clean electric energy, but the increasing number of end-of-life wind turbine blades has become a hazardous waste problem worldwide. A novel recycling approach based on mechanical grinding and combined with 3D printing techniques is a promising solution that will reduce waste at a low cost while retaining the excellent mechanical properties of recycled fabricated samples. Considering the material structure complexity of 3D printed samples, the Representative Volume Element (RVE) is a promising simulation model. This paper proposes a Modified Random Sequential Adsorption (MRSA) algorithm for the efficient generation of RVEs with hybrid and arbitrary-geometry reinforcements. Compared with the classical RSA algorithm, MRSA is advantageous in fiber intersection computational cost. The error between FEA and experiments is lower than results obtained from Mori-Tanaka and Halpin-Tsai. The effects of fiber content, fiber aspect ratio, fiber orientation and local fiber density are discussed. The model will be helpful for accurately predicting properties of 3D printing materials that use recycled wind turbine waste. [ABSTRACT FROM AUTHOR]

The external alternating magnetic field (AMF) strategy is the most promising research topic to solve the bottleneck of catalyst activity enhancement. However, the mechanism between the arrangement of the spin electrons under the AMF and the catalytic activity enhancement for water splitting is still unclear. Herein, we synthesize Fe 3 O 4 @CNTs heterostructure as a research model and resolve the mechanism by system theoretical analysis and in-situ Raman characterization. The multiple orbital interactions of σ(d z 2, p z , s) and π(d xz - p x , d yz - p y) promote the hexa-coordinated Fe oct for both the reductive HER and oxidative OER processes. The AMF excites the transition from low to high spin configurations of the Fe oct sites, which accelerates charge transfer of unpaired d electrons and optimizes adsorption and desorption interactions to intermediates during the reaction processes, resulting in a significant enhancement of the electrocatalytic activity (HER: 32 mV at 10 mA cm−2, OER: 179 mV at 100 mA cm−2). [Display omitted] • Density functional theory calculations reveal the high catalytic activity of hexa-coordinated iron sites. • Constructing heterostructures and applying external magnetic fields jointly influence material activity. • Mechanism for enhancing the activity of high-spin state electron orbitals through external magnetic field regulation. • In-situ Raman real-time monitoring of highly active FeOOH species during the reaction. [ABSTRACT FROM AUTHOR]

In recent years, the prevention and control of water pollution has received extensive attention. There is a need to develop simple and effective strategies for the rapid detection of metal ions and dissolved organic matter (DOM) in order to improve water quality. To this end, the first copper nanoclusters (CuNCs)-based fluorescent sensor array was done to identify 12 metal ions (Pb2+, Fe3+, Cu2+, Cd2+, Cr3+, Co2+, Ni2+, Zn2+, Ag+, Fe2+, Hg2+, and Al3+) and DOM (humic substances, lipids, fatty acids, amino acids, and lignans). The results revealed that CuNCs that were synthesized with polyethyleneimine (PEI), histidine (His), and glutathione (GSH) exhibited different binding abilities to metal ions and DOM. These unique fluorescence responses were analyzed using principal component analysis (PCA) and linear discriminant analysis (LDA) to identify metal ions and DOM in the buffer. The aforementioned 12 metal ions were classified at a limit concentration of 1.5 μM. Moreover, quantification of metal ions was achieved even at a low concentration of 0.83 μM (Zn2+). This array also worked well in the recognition of metal ions in tap water as well as distinguishing riverine and seawater samples of different regions, which was of great significance in environmental monitoring. [Display omitted] • The first copper nanoclusters-based fluorescent sensor array is constructed. • 12 metal ions are successfully identified even at a low concentration of 5 μM. • 6 dissolved organic matter (DOM) are successfully identified by the sensor array. • 6 water samples are identified based on fluorescence responses of ions and DOM. [ABSTRACT FROM AUTHOR]

Millions of North Americans stopped riding public transit in response to COVID-19. We treat this crisis as a natural experiment to illustrate the importance of public transit in riders' abilities to access essential destinations. We measured the impacts of riders forgoing transit through a survey of transportation barriers completed by more than 4,000 transit riders in Toronto and Vancouver (Canada). We used Heckman selection models to predict six dimensions of transport disadvantage and transport-related social exclusions captured in our survey. We then complemented model results with an analysis of survey comments describing barriers that individuals faced. Lack of access to alternative modes is the strongest predictor of a former rider experiencing transport disadvantage, particularly neighborhood walkability and vehicle ownership. Groups at risk of transport disadvantage before COVID-19, particularly women and people in poorer health, were also more likely to report difficulties while avoiding public transit. Barriers described by respondents included former supports no longer offering rides, gendered household car use dynamics, and lack of culturally specific or specialized amenities within walking distance. Policymakers should plan for a level of redundancy in transportation systems that enables residents to access essential destinations when unexpected service losses occur. Designing communities that enable residents to walk to those essential destinations will help reduce the burdens faced by transit riders during crises that render transit unfeasible. At the same time, planners championing active travel as an alternative to transit during such crises also need to devise solutions for former transit riders for whom active travel is ill suited, for example, due to physical challenges with carrying groceries or needing to chaperone children. [ABSTRACT FROM AUTHOR]

[Display omitted] • By optimizing the internal electronic structure and exposing more active sites. • The synergistic effect of heterogeneous atoms and oxygen defects. • The unique hexagonal morphology is more favorable to the exposure of active sites. • The highly active and stable bifunctional cobalt oxide-based catalysts. Undesirable conductivity and insufficient electrocatalytic activity are the current bottlenecks of cobalt tetroxide from achieving efficient water electrolysis. Herein, by optimizing the internal electronic structure and the controlled design of the morphology, we design a unique hexagonal Mn-Co 3 O 4 -200 nanostructure that exhibits superior water electrolysis performance with low overpotentials and excellent long-term durability under strongly alkaline conditions, outperforming many other previously reported cobalt oxide-based compounds. Theoretical combined with characterization analysis indicates that introduced Mn atoms induce an increase in the high spin-orbital occupancy of Co2+ to optimize free energy of the OOH*→O 2 step, which excites the catalytic activity of the Co sites, resulting in a substantial increase in the catalytic activity of the Mn-Co 3 O 4. Furthermore, we briefly summarize the catalytic activity variation pattern of several catalysts with different microscopy morphologies and innovatively propose a more intuitive means to evaluate their exposed active areas. Compared with other morphologies, the special hexagonal morphology with abundant pores and large effectively exposed catalytic surface area can promote the exposure rate of active centers, mass transfer of electrolytes and diffusion of hydrogen and oxygen in the electrocatalytic process, thus accelerating the rate of electrocatalytic reactions. [ABSTRACT FROM AUTHOR]

• Comprehensive comparison of multiple therapies in patients with ERBB2-altered NSCLC. • Chemotherapy plus immunotherapy or anti-angiogenesis therapy showed better mPFS than TKIs in the ERBB2-altered NSCLC. • In the same therapies, patients with ERBB2 mutation or ERBB2 amplification showed no statistical significance in PFS. Although the treatment of ERBB2-altered non-small cell lung cancer (NSCLC) has been studied for many years, there are no comprehensive studies to evaluate the benefits of various therapies as first-line treatment. Through the development of immunotherapy, more and more different combination treatments were applicated in clinical practice, therefore, we conducted a multicenter retrospective study to evaluate the efficacy of different treatments. We enrolled patients with ERBB2-altered NSCLC who had undergone at least one-line systemic anticancer treatment to evaluate the efficacy of first-line chemotherapy alone (Chemo), anti-ERBB2 tyrosine kinase inhibitor (TKI), chemotherapy plus immunotherapy (Chemo + Immuno), chemotherapy plus anti-angiogenesis therapy (Chemo + Antiangio) and chemotherapy combined with immunotherapy and anti-angiogenesis therapy (Chemo + Immuno + Antiangio). The clinical outcomes included objective response rate (ORR), disease control rate (DCR), median progression-free survival (mPFS), one-year and three-year survival rate. We enroll 36 patients harboring ERBB2 mutation and 29 with ERBB2 amplification. The overall ORR was 30.8%, DCR was 69.2% and mPFS was 5.7 months. Chemo + Immuno and Chemo + Antiangio both achieved longer mPFS than TKI (7.8 vs 3.6 months, HR: 0.24, 95 %CI: 0.09–0.64, P = 0.002; 5.9 vs 3.6 months, HR: 0.36, 95 %CI: 0.15–0.88, P = 0.019; respectively), while there was no significant difference in mPFS between Chemo + Immuno or Chemo + Antiangio and Chemo (both P > 0.05), the mPFS of the first two was longer. For ERBB2-mutant patients, the mPFS was 5.9 months, and Chemo + Immuno and Chemo + Antiangio both achieved longer mPFS than TKI (12.9 vs 2.9 months, HR: 0.15, 95 %CI: 0.03–0.68, P = 0.005; 7.1 vs 2.9 months, HR: 0.50, 95 %CI: 0.29–0.88, P = 0.009, respectively). In the same therapies, patients with ERBB2 mutation or ERBB2 amplification showed no statistical significance in PFS (both P > 0.05). In the first-line treatment of ERBB2-altered NSCLC, chemotherapy combined with immunotherapy or anti-angiogenesis therapy may have greater survival benefits than ERBB2-target therapy, but the efficacy may not be better than that of chemotherapy. [ABSTRACT FROM AUTHOR]

We present an electrodeposition strategy to construct heterostructures nickel selenide (NiSe) and carbon nanotubes (CNTs), namely NiSe@CNTs, to tune the electronic structure of the Ni sites, thus stimulating the hidden catalytic potential of the Ni sites. As expected, the optimized NiSe@CNTs exhibits unprecedentedly ultra-high activity for HER (27 mV at 10 mA cm−2) and OER (145 mV at 100 mA cm−2) and outstanding long-term durability (730 h). Based on the systematic characterization and DFT results, the Ni sites with increased electron density induced by π-electron off-domain of CNTs not only greatly optimize the H* adsorption kinetics but also reduce the energy barrier of the *O→*OOH step, demonstrating the enhanced intrinsic catalytic activity. Furthermore, the introduced CNTs not only avoid aggregation of nanoparticles but also reduce particle size, thus increasing the number of exposed Ni active sites. This study provides guidance for the exploration of catalysts with ultra-high activity and durability. [Display omitted] • The ultra-high activity for HER (27 mV at 10 mA cm-2) and OER (145 mV at 100 mA cm-2) and outstanding long-term durability (730 h). • Internal and external means to enhance catalytic activity. • The interfacial effect between NiSe and CNTs in the heterostructure exacerbates the further π-electrons delocalization of CNTs. [ABSTRACT FROM AUTHOR]

Sarcoidosis is a multisystem inflammatory disease characterized by the development of Th1/Th17/regulatory T cells (Tregs)-related non-caseating granulomas. Phosphoinositide-3 kinases δ/γ (PI3Kδ/γ) play an important role in the maintenance of effective immunity, especially for Tregs homeostasis and stability. In the present study, superoxide dismutase A (SodA) stimulation was used to establish the sarcoidosis mouse model. The second immune stimulus was accompanied by CAL-101 (PI3Kδ inhibitor) or AS-605240 (PI3Kδ/γ inhibitor) treatment. To detect the effect of the PI3Kδ/γ inhibitor on the morphology of pulmonary granuloma and the activation of the PI3K signaling pathway, hematoxylin and eosin staining and immunofluorescence and western blotting was used, respectively. Fluorescence-activated cell sorting analysis and reverse transcription-quantitative PCR were adopted to detect the effect of the PI3Kδ/γ inhibitor on the SodA-induced sarcoidosis mouse model in respect to immune cell disorder and the function of Treg cells, with CD4+CD25- T cells and CD4+CD25+ T cells sorted by magnetic cell sorting. The results demonstrated that the inhibition of PI3Kδ/γ by transtracheal CAL-101/AS-605240 administration facilitated pulmonary granuloma formation. These therapeutic effects were associated with certain mechanisms, including suppressing the aberrantly activated PI3K/Akt signaling in both pulmonary granuloma and Tregs, particularly rescuing the suppressive function of Tregs. Notably, CAL-101 was more effective in immune modulation compared with AS-605240 and could overcome the aberrantly activated Akt in the lung and Tregs. These results suggest that PI3K/Akt signaling, especially the PI3Kδ subunit, can play a key role in optimal Tregs-mediated protection against pulmonary sarcoidosis. Therefore, transtracheal usage of PI3Kδ/γ inhibitors is an attractive therapy that may be developed into a new immune-therapeutic principle for sarcoidosis in the future. [ABSTRACT FROM AUTHOR]

Dendrimers capped with amino groups (DEN) are grafted to graphene oxide (GO) nanosheets for subsequent functionalization of GO with gadolinium diethylene triamine pentaacetate (Gd-DTPA) and prostate stem cell antigen (PSCA) monoclonal antibody (mAb). The as-prepared GO-DEN(Gd-DTPA)-mAb exhibits very low cytotoxicity, negligible hemolytic activity, and no perceptible toxic effects in mice. GO-DEN(Gd-DTPA)-mAb can specifically target PSCA over-expressed cancer cells to give a significant T 1 -weighted contrast enhancement effect. The in vivo magnetic resonance imaging results indicate that GO-DEN(Gd-DTPA)-mAb can be used as a targeted contrast agent for prostate tumor imaging. GO-DEN(Gd-DTPA)-mAb can be efficiently loaded with doxorubicin hydrochloride (DOX), and the resulting GO-DEN(Gd-DTPA)-mAb/DOX exhibits enhanced cytotoxicity to PC-3 cells due to good targeting performance. By following the PC-3 tumor growth in mouse model after intravenous administration of GO-DEN(Gd-DTPA)-mAb/DOX, it is demonstrated that GO-DEN(Gd-DTPA)-mAb can targetedly deliver anticancer drugs to malignant prostate tumors and inhibit tumor growth. [ABSTRACT FROM AUTHOR]

Water-soluble nanoparticles (Ir/PGlc-NP, Ir/β-1,3-glucan-NP) based on water-soluble glycopolymers (PGlc), β-1,3-glucan polysaccharide, and conjugated phosphorescent Ir (III) complexes were successfully synthesized by self-assembly. The obtained nanoparticles have good spherical morphological characterization with a mean diameter of 50 nm measured by TEM. Ir/PGlc-NP and Ir/β-1,3-glucan-NP showed the same emission maxima at 565 nm in aqueous solution and both caused effective apoptosis and death of HepG2 and Hela cells after being irradiated at 445 nm for 30 min in vitro. Fluorescence cellular imaging was conducted by confocal laser scanning microscopy (CLSM) using HepG2 cells as the model cell in which the nanoparticles had successfully entered into the cytoplasm with high brightness. Furthermore, after injecting the nanoparticles into live mice in vivo, the real-time fluorescence imaging as well as the nanoparticles distribution in organs at 24 hours after administration indicated that these nanoparticles can serve as fluorescent imaging contrast for further biological applications. [ABSTRACT FROM AUTHOR]