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Anchoring of NiCoxalloy nanoparticles (NPs) onto nitrogen vacancy-rich carbon nitride nanotubes (NiCox/VN-CNNTs) with porous structure was well designed toward promoting efficiently photocatalytic conversion of CO2into solar fuels in the presence of water vapor. NiCox/VN-CNNTs exhibit not only highly efficient generation of CO, but also a significant amount of CH4, compared to only CO and a trace amount of CH4on pristine VN-CNNTs and single metal-loading VN-CNNTs. The photoexcited dynamics show that the synergy modulation of the NiCoxalloy site and vacancy leverage of CNNT is beneficial for efficient separation of photoinduced electron–hole pairs, in favor of the multiple electron-involving reduction pathways for CH4formation. Density functional theory simulations validate that the loaded NiCoxalloy NPs also provide the driving force for accelerating the absorption of CO2, reducing the free energy of CO2-to-CH4photoreduction, and decreasing desorption energy of the forming CH4. This work presents a viewpoint to engineer the composition of nanoalloy-based photocatalysts for improved CO2-to-CH4photoreduction.

Using the electrochemical CO2reduction reaction (CO2RR) with Cu-based electrocatalysts to achieve carbon-neutral cycles remains a significant challenge because of its low selectivity and poor stability. Modulating the surface electron distribution by defects engineering or doping can effectively improve CO2RR performance. Herein, we synthesize the electrocatalyst of Vo-CuO(Sn) nanosheets containing oxygen vacancies and Sn dopants for application in CO2RR-to-CO. Density functional theory calculations confirm that the incorporation of oxygen vacancies and Sn atoms substantially reduces the energy barrier for *COOH and *CO intermediate formation, which results in the high efficiency, low overpotential, and superior stability of the CO2RR to CO conversion. This electrocatalyst possesses a high Faraday efficiency (FE) of 99.9% for CO at a low overpotential of 420 mV and a partial current density of up to 35.22 mA cm–2at −1.03 V versus reversible hydrogen electrode (RHE). The FECOof Vo-CuO(Sn) could retain over 95% within a wide potential area from −0.48 to −0.93 V versus RHE. Moreover, we obtain long-term stability for more than 180 h with only a slight decay in its activity. Therefore, this work provides an effective route for designing environmentally friendly electrocatalysts to improve the selectivity and stability of the CO2RR to CO conversion.

Suppressing the recombination of light-induced carriers in semiconductor photocatalysts is crucial but challenging for high-activity photocatalysis. In addition to the current substantially developed strategies, such as the built-in field of catalytic heterostructures, other promising alternatives need to be explored. Herein, a mangosteen peel waste-derived 3D graphene hybrid material with a magnetic interfacial junction was constructed to obtain insights into its highly efficient photocatalytic performance by boosting carrier transfer efficiency with the assistance of a magnetic field. The spin-related behavior of the ferromagnetic alignment of the magnetic interfacial junction of the designed 3D graphene/Cd0.5Zn0.5S hybrids plays an essential role in improving the photocatalytic performance, with ciprofloxacin degradation efficiency reaching 95% removal in 15 min, which is a 67% reduction in photocatalytic degradation time. This photocatalytic performance is outstanding in comparison to previous research without an applied external magnetic field. With low energy consumption, this magnetic field strategy provides a new perspective for water treatment as well as various catalytic fields.

The electrochemical CO2reduction reaction (CO2RR) to HCOOH offers a promising strategy for a carbon-neutral cycle. Sn-Based materials have been demonstrated as applicable in extensive studies of CO2RR to HCOOH, but great challenges still remain, including the weak CO2adsorption and narrow potential window as well as low stability. Herein, we developed ultrasmall Sn nanoparticles inlaid on N/P-doped carbon (Sn@NPC) composites by an upcycling design using Sn electroplating sludge. The obtained Sn@NPC electrode exhibited a higher Faradaic efficiency of 87.93% for HCOOH at 1.05 V vs.RHE and an FE over 80% within a 500 mV broad potential window. Moreover, the Sn@NPC electrode achieved excellent long-term stability up to 105 h, which was superior to that of most Sn-based catalysts in similar systems. Density functional theory calculations demonstrated that Sn@NPC could enhance CO2adsorption, which led to stronger *OCHO adsorption, weaker *HCOOH adsorption and faster electron/mass transport. This work may provide a promising lead for recycling metal from electroplating sludge and for the design of efficient and stable catalysts for the CO2RR.

Online ride-hailing services play a crucial role in daily transportation, However, challenges persist in certain regions with limited access, and drivers encounter difficulties in receiving orders. Accurate prediction of short-term origin-destination (OD) demand is crucial for addressing these issues. This study leverages recent advancements in artificial intelligence and big data to introduce a spatiotemporal encoder-decoder network with a residual feature extractor (RF-STED) for short-term OD demand prediction in online ride-hailing services. The RF-STED model, built on deep learning models such as graph convolutional networks and convolutional long short-term memory (Conv-LSTM), includes spatiotemporal networks, encoding layers, and a residual feature extractor. The spatiotemporal network has two branches: branch one processes multi-pattern OD data using a multi-pattern temporal feature extraction module, utilizing a multi-channel Conv-LSTM to capture temporal correlations. Branch two utilizes a multi-spatial feature extraction module to convert OD pair associations into a spatial topology, extracting multi-spatial correlations. The encoding layer captures spatiotemporal dependencies, while the residual feature extractor decodes compressed vectors back into an OD graph for forecasting future demand. Experiments with a Manhattan taxi dataset in the U.S. show the RF-STED model outperforms 10 baseline models and four ablation models. The results emphasize the model’s strength and robustness in short-term OD flow prediction.

While the issues of childlessness and social support in old age have received considerable attention in more developed countries, the phenomenon of aging without children in China has been relatively underexplored. The existing, albeit limited, literature highlights the vulnerability of the childless elderly in China and the inadequacy of social care services, which is predominantly directed toward most impoverished groups. This study examines the care arrangements and social support mechanisms for childless older people in urban China, emphasizing the role of community-level officers in this context. Drawing on in-depth interviews conducted in 2019 with 27 childless elderly individuals and 10 community-level officers in Shanghai, the study reveals the formation of community-based substitute families. These substitute families, comprising neighbors, extended family members, and friends, provide daily assistance, emotional support, and sometimes intensive care. The establishment of these substitute families hinges on the childless individuals’ ability to navigate public and social resources, as well as the institutionalized mobilization and informal work strategies of community-level officers. We argue that the care arrangements for childless older people are significantly shaped by the state's aging-in-place elder care policy. However, the effectiveness of this policy is mediated by the informal work strategies of community-level officers and the proactive care planning by the childless elderly themselves. Our findings offer important insights for improving the current family-based elder care policies and enrich our understanding of aging without children in urban China.

The cobalt-based spinel oxides MCo2O4(M = Ni, Mn, Cu, Fe, etc.) have garnered significant attention due to their potential applications in energy storage. In this study, ultra-thin FeCo2O4nanosheets have been synthesized through a facile electrodeposition method and used as binder-free electrodes for high-performance supercapacitors. The results indicate that the FeCo2O4nanosheet (FCS) electrode obtained through 5 min of electrodeposition using ferrous salt (FeSO4) as the precursor has a more abundant pore structure and exhibits the best electrochemical performance. The specific capacitance of the FeCo2O4nanosheets electrode reaches 679 F g−1at a current density of 1 A g−1, and it retains 92.9 % of its initial capacitance after undergoing 5000 cycles. In addition, the assembled FeCo2O4nanosheet (FCS)//activated carbon (AC) asymmetric supercapacitor shows a high energy density of 62.5 Wh kg−1at 750 W kg−1and with a capacitance retention of 91.3 % after 5000 cycles. Furthermore, the electrodeposition method utilized in the synthesis of the FeCo2O4nanosheets is cost-effective, environmentally friendly, and can be employed to fabricate other MCo2O4materials with superior electrochemical properties.

A new-type multiple-source heat pump cycle with two-stage compression was established on the basis of the problems of similarly existing heat pumps. The equivalent temperature levels of typical evaporators are applied to the different heat sources of the proposed cycle, and the high-temperature heat sources are shown to enhance vapor injection. Then, the mathematical model and prototype are developed, and the results from experimental simulation and validation showed that the solar collector can improve the heating performance of the proposed heat pump system. In the middle-temperature heating period, the outdoor temperature is less than −25°C, and the average coefficient of performance (COP) value of the proposed heat pump was 4.2, which was greater than the COPs of conventional ground source heat pumps.

N-type BiVO4 films coupled with p-type copper oxide nanoparticles were investigated as photoanodes for water oxidation. Compared with the BiVO4 film, the Cu2O/BiVO4, CuO/BiVO4 and CuxO/BiVO4 films all showed significantly improved photoelectrochemical water oxidation activity and stability. As expected, the radiative recombination of charge on the three kinds of copper oxide/BiVO4 films was decreased due to the p-n junction effect between copper oxide and BiVO4. However, our investigations indicated that the electrocatalytic water oxidation on the copper oxide could be initiated when the copper oxide/BiVO4 photoanodes were irradiated by solar light; therefore, the copper oxide-coupling resulted in a more obvious improvement in the water oxidation kinetics of BiVO4 than the thermodynamic improvement in the charge separation of BiVO4. Of the three kinds of copper oxide/BiVO4 films, the CuxO/BiVO4 film comprising BiVO4 film coupled with a combination of Cu2O/CuO nanoparticles showed the best solar water oxidation performance due to the better electrocatalytic activity for water oxidation of CuxO compared with Cu2O or CuO alone. The kinetic investigations and analyses in the present work provide comprehensive insight into the mechanism of the copper oxide/BiVO4 photoanodes for solar water oxidation.

Manipulation of interfacial charge separation and transfer is one of the primary breakthroughs to improve the water oxidation activity and stability of BiVO4photoanode. In the present work, a CoMoO4-coupled BiVO4(BiVO4/CoMoO4) film was designed and prepared as the photoanode for photoelectrochemical (PEC) water oxidation. Compared with the bare BiVO4film, obviously improved PEC water oxidation performance was observed on the BiVO4/CoMoO4film. Specifically, a higher water oxidation photocurrent density of 3.04 mA/cm2at 1.23 V versus RHE was achieved on the BiVO4/CoMoO4photoanode, which is of about 220% improvement over bare BiVO4photoanode (1.34 mA/cm2at 1.23 V vs RHE). In addition, the BiVO4/CoMoO4film photoanode was of better stability and faster hole-to-oxygen kinetics for water oxidation, without significant activity attenuation for 6 h of reaction at 0.65 V versus RHE. The enhanced water oxidation performance on the BiVO4/CoMoO4film photoanode can be ascribed to the synergistic effect of the following factors: (i) thermodynamically, the photogenerated holes of BiVO4are directionally transferred to CoMoO4through their physical coupling interface and valance band potential matching; and (ii) kinetically, the transferred holes induce the formation of Co3+-active sites on CoMoO4that could synergistically oxidize H2O to molecular O2with stable activity.

Photoreduction of diluted CO2is an effective strategy for the sustainable and environmentally friendly development of energy. In this study, lattice strain in NiSe is modulated through the control of the Ni concentration for the photoreduction of diluted CO2. Refined XRD data and the results of the Williamson–Hall analysis indicate that the lattice strain is induced by lattice distortion caused by an absence of Ni atoms in the crystal lattice. In pure CO2, the cumulative CO yield and selectivity of Ni1−xSe nanoflowers reached approximately 19.39 µmol and 90.7 % in 3 h, respectively. For lower CO2concentrations of 0.1 and 0.05 atm, the CO selectivity of Ni1−xSe was approximately 72.7 % and 61.7 %, respectively. On characterization of the synthesized nanoflowers, we deduced that the lattice-strained Ni1−xSe exhibited a favorable electronic band structure that improved the separation efficiency of the photogenerated carriers. DFT calculations results revealed that the lattice strain significantly facilitated the adsorption and activation of CO2, which resulted in highly efficient CO2photoreduction. This study provides an effective strategy for the design and synthesis of high-performance catalysts based on the modification of their crystal structures.

A polymerase chain reaction (PCR) targeted to the central portion of the bovine herpesvirus 1 (BHV1) genome, and overlapping the 3' untranslated end of the gI glycoprotein, was used to amplify BHV1 genomic sequences. PCR products generated from cell cultures infected with BHV1.1 were consistently smaller than the corresponding products from cells infected with BHV1.2. The nature of the sequence differences between these isolates within the target region was found to be a consequence of variable numbers of small GC rich repeats, particularly the sequence 5'-G(A/T)CC-3', present in the region downstream of the gI coding region. Based on these differences a modified PCR protocol which readily discriminated between several BHV1.1 and BHV1.2 strains was devised.

N-type BiVO4films coupled with p-type copper oxide nanoparticles were investigated as photoanodes for water oxidation. Compared with the BiVO4film, the Cu2O/BiVO4, CuO/BiVO4and CuxO/BiVO4films all showed significantly improved photoelectrochemical water oxidation activity and stability. As expected, the radiative recombination of charge on the three kinds of copper oxide/BiVO4films was decreased due to the p-n junction effect between copper oxide and BiVO4. However, our investigations indicated that the electrocatalytic water oxidation on the copper oxide could be initiated when the copper oxide/BiVO4photoanodes were irradiated by solar light; therefore, the copper oxide-coupling resulted in a more obvious improvement in the water oxidation kinetics of BiVO4than the thermodynamic improvement in the charge separation of BiVO4. Of the three kinds of copper oxide/BiVO4films, the CuxO/BiVO4film comprising BiVO4film coupled with a combination of Cu2O/CuO nanoparticles showed the best solar water oxidation performance due to the better electrocatalytic activity for water oxidation of CuxO compared with Cu2O or CuO alone. The kinetic investigations and analyses in the present work provide comprehensive insight into the mechanism of the copper oxide/BiVO4photoanodes for solar water oxidation.