Hospitals are important sources of pollutants resulted from diagnostic, laboratory and research activities as well as medicine excretion by patients, which include active component of drugs and ...metabolite, chemicals, residues of pharmaceuticals, radioactive markers, iodinated contrast media, etc. The discharge of hospital wastes and wastewater, especially those without appropriate treatment would expose the public in danger of infection. In particular, under the Coronavirus Disease 2019 (COVID-19) pandemic context in China, it is of great significance to reduce the health risks to the public and environment. In this study, technologies of different types of hospital wastes and wastewater disinfection have been summarized. Liquid chlorine, sodium hypochlorite, chlorine dioxide, ozone, and ultraviolet irradiation disinfection are commonly used for hospital wastewater disinfection. While incineration, chemical disinfection, and physical disinfection are commonly used for hospital wastes disinfection. In addition, considering the characteristics of various hospital wastes, the classification and selection of corresponding disinfection technologies are discussed. On this basis, this study provides scientific suggestions for management, technology selection, and operation of hospital wastes and wastewater disinfection in China, which is of great significance for development of national disinfection strategy for hospital wastes and wastewater during COVID-19 pandemic.
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•O3, UV, chlorine disinfectants are used for hospital wastewater disinfection.•Incineration, chemical and physical techniques are used to disinfect hospital wastes.•Providing suggestions for hospital wastes and wastewater disinfection during COVID-19.•The chlorine disinfection and incineration are primarily recommended.
•The concentration and yield of VFAs were highest at pH 6.0.•A more efficient and economical temperature for VFAs production is 35°C.•An OLR of 11g/Ld is suitable for VFAs production.•Ammonia ...nitrogen was released during the anaerobic acidification.
The effects of pH, temperature, and organic loading rate (OLR) on the acidogenesis of food waste have been determined. The present study investigated their effects on soluble chemical oxygen demand (SCOD), volatile fatty acids (VFAs), volatile solids (VS), and ammonia nitrogen (NH4+–N). Both the concentration and yield of VFAs were highest at pH 6.0, acetate and butyrate accounted for 77% of total VFAs. VFAs concentration and the VFA/SCOD ratio were highest, and VS levels were lowest, at 45°C, but the differences compared to the values at 35°C were slight. The concentrations of VFAs, SCOD, and NH4+–N increased as OLR increased, whereas the yield of VFAs decreased from 0.504 at 5g/Ld to 0.306 at 16g/Ld. Acetate and butyrate accounted for 60% of total VFAs. The percentage of acetate and valerate increased as OLR increased, whereas a high OLR produced a lower percentage of propionate and butyrate.
Due to global climate change as well as economic concern of network operators, energy consumption of the infrastructure of cellular networks, or "Green Cellular Networking," has become a popular ...research topic. While energy saving can be achieved by adopting renewable energy resources or improving design of certain hardware (e.g., power amplifier) to make it more energy-efficient, the cost of purchasing, replacing, and installing new equipment (including manpower, transportation, disruption to normal operation, as well as associated energy and direct cost) is often prohibitive. By comparison, approaches that work on the operating protocols of the system do not require changes to current network architecture, making them far less costly and easier for testing and implementation. In this survey, we first present facts and figures that highlight the importance of green mobile networking and then review existing green cellular networking research with particular focus on techniques that incorporate the concept of the "sleep mode" in base stations. It takes advantage of changing traffic patterns on daily or weekly basis and selectively switches some lightly loaded base stations to low energy consumption modes. As base stations are responsible for the large amount of energy consumed in cellular networks, these approaches have the potential to save a significant amount of energy, as shown in various studies. However, it is noticed that certain simplifying assumptions made in the published papers introduce inaccuracies. This review will discuss these assumptions, particularly, an assumption that ignores the effect of traffic-load-dependent factors on energy consumption. We show here that considering this effect may lead to noticeably lower benefit than in models that ignore this effect. Finally, potential future research directions are discussed.
Ce substitution level in Nd-Fe-B magnets has been significantly increased via the binary main phase (BMP) approach, i.e. sintering the mixture of Ce-free and Ce-containing RE2Fe14B (RE, rare earth) ...powders. REFe2 phase that forms in the high Ce-containing Nd-Ce-Fe-B magnets has been considered to be harmful to magnetic performance due to its soft magnetism. In this work, we found that REFe2 phase with lower melting point than the 2:14:1 phase plays positive role on optimizing the microstructure and retaining magnetic performance of the Nd-Ce-Fe-B BMP magnets. The wettability of 2:14:1 phase can be improved by sintering above the melting point of REFe2 phase, which promotes densification of the magnet and the formation of continuous and smooth grain boundary (GB) phases. This contributes to the weakened short-range exchange coupling between adjacent grains, hence ensures superior magnetic performance of BMP magnets to the single main phase (SMP) ones with the same average composition. As a result, magnetic properties of Br = 12.4 kG, Hcj = 9.0 kOe and (BH)max = 36.7 MGOe can be obtained even when 45 wt % Ce substitutes for Nd in the BMP magnets.
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Sleep deprivation (SD) correlates with exacerbated systemic inflammation after sepsis. However, the underlying mechanisms remain unclear. This study aimed to evaluate the roles and mechanisms of SD ...in inflammatory organ injury after lipopolysaccharide (LPS) administration.
Mice were intraperitoneally injected with LPS followed by 3 consecutive days of SD. The pseudo germ-free (PGF) mice received fecal microbiota transplant by being gavaged with supernatant from fecal suspension of septic mice with or without SD. The subdiaphragmatic vagotomy (SDV) or splenectomy was performed 14 days prior to LPS injection or antibiotics administration.
Post-septic SD increased the plasma levels of interleukin (IL)-6 and tumor necrosis factor-α (TNF-α), reduced IL-10 plasma level, increased spleen weight, and promoted inflammatory injury of the lung, liver and kidney. The relative abundance of Proteobacteria and its subgroups were increased after post-septic SD. PGF mice transplanted with fecal bacteria from septic mice subjected to SD developed splenomegaly, systemic inflammation, organ inflammation and damage as their donors did. Intriguingly, SDV abolished the aggravated effects of SD on splenomegaly and inflammatory organ injury in septic mice received SD or in PGF mice transplanted with fecal bacteria from septic mice subjected to SD. Furthermore, splenectomy also abrogated the increase in IL-6 and TNF-α plasma levels and the decrease in IL-10 plasma level in PGF mice transplanted with fecal bacteria from septic mice subjected to SD.
Gut microbiota-vagus nerve axis and gut microbiota-spleen axis play key roles in modulating systemic inflammation induced by SD after LPS administration.
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Electrochemical reduction of CO2 to ethanol, a clean and renewable liquid fuel with high heating value, is an attractive strategy for global warming mitigation and resource utilization. However, ...converting CO2 to ethanol remains great challenge due to the low activity, poor product selectivity and stability of electrocatalysts. Here, the B‐ and N‐co‐doped nanodiamond (BND) was reported as an efficient and stable electrode for selective reduction of CO2 to ethanol. Good ethanol selectivity was achieved on the BND with high Faradaic efficiency of 93.2 % (−1.0 V vs. RHE), which overcame the limitation of low selectivity for multicarbon or high heating value fuels. Its superior performance was mainly originated from the synergistic effect of B and N co‐doping, high N content and overpotential for hydrogen evolution. The possible pathway for CO2 reduction revealed by DFT computation was CO2→*COOH→*CO→*COCO→*COCH2OH→*CH2OCH2OH→CH3CH2OH.
Efficient and selective electrochemical reduction of CO2 to ethanol was achieved on a nonmetallic B‐ and N‐co‐doped nanodiamond used as an electrocatalyst. The synergistic effect of co‐doping, N content, and H2 evolution potential were used as key factors for tailoring ethanol selectivity.
Dysregulated expression of microRNAs (miRNAs) in various tissues has been associated with a variety of diseases, including cancers. Here we demonstrate that miRNAs are present in the serum and plasma ...of humans and other animals such as mice, rats, bovine fetuses, calves, and horses. The levels of miRNAs in serum are stable, reproducible, and consistent among individuals of the same species. Employing Solexa, we sequenced all serum miRNAs of healthy Chinese subjects and found over 100 and 91 serum miRNAs in male and female subjects, respectively. We also identified specific expression patterns of serum miRNAs for lung cancer, colorectal cancer, and diabetes, providing evidence that serum miRNAs contain fingerprints for various diseases. Two non-small cell lung cancer-specific serum miRNAs obtained by Solexa were further validated in an independent trial of 75 healthy donors and 152 cancer patients, using quantitative reverse transcription polymerase chain reaction assays. Through these analyses, we conclude that serum miRNAs can serve as potential biomarkers for the detection of various cancers and other diseases.
Compared to single coatings, multiple-layer coatings or composite coatings could provide better and more durable corrosion protection to magnesium alloys. In this paper, a MgAl-LDH/Ni composite ...coating was successfully prepared on magnesium alloy AZ31B via preparation of a LDH primer, an electroless-deposited Ni-B (ENB) intermediate layer, and an electroless-deposited Ni-P(ENP) top layer. The surface morphologies, chemical compositions, and corrosion resistance of the composite coating were characterized and discussed. The results showed that nano-scale Ag particles acting as the activation sites were introduced onto the surface of the LDH layer after the activation process. Ni particles were deposited in the areas where Ag particles exist, and an intact Ni-B layer formed after 15 min of ENB plating. The total thickness of the composite coating is about 38 µm, in which the LDH layer is ~13 µm, and the EN coating is ~25 µm. The composite coating does not show any perforation after exposure to a 3.5 wt% NaCl solution for 210 h or 0.1 mol·dm−3 HCl solution for 30 h, attributed to the amorphous structure of the electroless-deposited nickel layer and the P-rich layer formed at the surface to hamper nickel oxidation. In comparison, obvious corrosion holes appeared on the LDH coating after immersion in a 3.5 wt% NaCl solution for 20 h or in a 0.1 mol·dm−3 HCl solution for 30 min. Furthermore, the EIS test results confirmed the durable corrosion protection of the composite coating to the magnesium alloy substrate.
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To improve the thermal stability of the Nd-Ce-Fe-B sintered magnets, Y was incorporated via the binary main phase (BMP) approach. At the same substitution level for Nd (9wt%), the absolute value of ...the coercivity temperature coefficient from 293 to 393K for the Nd-Ce-Y-Fe-B magnet is 16.2% lower than that for the Nd-Ce-Fe-B one. This is attributed to the weakened temperature dependence of the magnetocrystalline anisotropy field and the magnetization as Y preferably enters into the 2:14:1 phase. It suggests that Y and Ce co-substitution for Nd is appealing to prepare low-cost RE-Fe-B permanent magnets with improved thermal stability.
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Highly efficient photocatalytic hydrogen evolution (PHE) is highly desirable for addressing the global energy crisis and environmental problems. Although much attention has been given to ...electron–hole separation, ridding photocatalysts of poor efficiency remains challenging. Here, a two‐electron catalytic reaction is developed by utilizing the distinct trion behavior of ReS2 and the efficient reduction of two H+ (2H+ + 2e− → H2) is realized. Due to the monolayer‐like structure of the catalyst, the free electrons in ReS2 can be captured by the tightly bound excitons to form trions consisting of two electrons and one hole. These trions can migrate to the surface and participate in the two‐electron reaction at the abundant active sites. As expected, such a two‐electron catalytic reaction endows ReS2 with a PHE rate of 13 mmol g−1 h−1 under visible light irradiation. Meanwhile, this reaction allows the typically poor PHE efficiency of pure transition metal dichalcogenides to be overcome. The proposed two‐electron catalytic reaction provides a new approach to the design of photocatalysts for PHE.
A two‐electron catalytic reaction is first demonstrated by utilizing the trions in ReS2 and a superior photocatalytic hydrogen evolution rate of 13 mmol g−1 h−1 is achieved, which surpasses the rates of most reported transition metal dichalcogenide composite photocatalysts. This work sheds light on the two‐electron catalytic reaction of photogenerated excitons in semiconductors, providing a new approach to the design of highly efficient photocatalysts.
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