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Filters in heating, ventilation, and air-conditioning (HVAC) systems are the most prevalent air cleaning method in residential environments in North America. This study evaluated the long-term impact of residential filtration systems on indoor particle concentrations by examining concentration measurements from low-cost monitors over one year in twenty homes in Toronto, Ontario, Canada. These concentration results suggested that in general, indoor concentration had a similar seasonal trend as the ambient concentration, and indoor activities (e.g., cooking) elevated indoor particle levels for 40-50% of the time. Further, the impacts of electret filters were examined using a non-electret filter with a minimum efficiency reporting value (MERV) of 8 as the reference point at each home. The mean effectiveness of the filters (MERV 8E=-4.19%, MERV 11E=-0.51%, and MERV 14E=14.5%) were lower than values found in the literature, most likely due to lower HVAC system runtime in our sample of homes (median=9.6%). Overall, this filter effectiveness analysis reveals that the real-life filter performance was strongly influenced by system and house characteristics (e.g., system runtime, in-situ efficiency, air change rate, and particle source strength), and thus can be different from modeling and laboratory test results. [ABSTRACT FROM AUTHOR]

Aiming at the problem of high‐speed motors being limited by multiple physical fields, which makes it difficult to achieve ultra‐high‐speed stable operation and develop towards higher speeds and higher power, an ultra‐high‐speed bearingless permanent magnet synchronous motor (UBPMSM) is proposed. Based on the mathematical model of suspension force for the bearingless permanent magnet motor considering the rotor eccentricity and load condition, the electromagnetic design method for UBPMSM is proposed. According to this method, the topology, torque system and suspension force system of a 10 kw 100k r/min UBPMSM are theoretically designed. The finite element method (FEM) is used to analyse the electromagnetic performance, which verifies the correctness of the proposed design method for UBPMSM. Further analysis and selection of winding span combinations are conducted to obtain better torque and suspension performance. [ABSTRACT FROM AUTHOR]

Flood event consists of peak discharge and flood volume that are mutually correlated and can be described by a copula function. For a given bivariate joint distribution, a choice of design return period will lead to infinite combinations of peak discharge and flood volume. A boundary identification method is developed to define the feasible ranges of flood peak and volume suitable for combination, and two combination methods, i.e., equivalent frequency combination (EFC) method and conditional expectation combination method for estimating unique bivariate flood quantiles are also proposed. Monte Carlo simulation method is used to evaluate the performance of these combination methods. The Geheyan reservoir in China was selected as case study. It is shown that the joint design values estimated by the two proposed combination methods are both within the feasible range, which means that the methods could be selected for designing unique flood quantiles. The proposed bivariate combination methods are also compared with univariate method, and the reservoir water level estimated by EFC method is higher than the other methods, which means the EFC method is safer for reservoir design. The developed approach provides an applicable way for the identification of feasible range and flood quantile estimation. [ABSTRACT FROM AUTHOR]

Indole is one of the utmost important heterocycles as it is an essential nucleus of many pharmaceutical compounds. Its aza-Michael reaction, however, is underdeveloped because of the moiety's inherent characteristics. Here, a potassium hydroxide catalysed intermolecular aza-Michael reaction of 3-cyanoindole with aromatic enones is described. A variety of chalcone derivatives are well tolerated and afford the corresponding N-adducts in moderate to high yields. The use of a cheap catalyst, low catalyst loading, mild reaction temperature, and good substrate tolerance make this procedure a direct and facile method for the preparation of N1-functionalized indoles. [ABSTRACT FROM AUTHOR]

Selenium deficiency in crops has become a subject of growing concern where soil Se concentration is low. The mechanisms of Se translocation in the soil-rice system is very complex and the influence of heavy metal elements and nutrient concentrations on Se translocation in the soil-rice system is unknown. Our study investigated concentrations of Se, heavy metals like Hg, Cd, and Pb, and nutrient elements like Ca, K, P, and S in soils and rice tissues (roots, stems, and grains) in different industrial regions in Jiangsu Province, China. The transfer of Se in the soil-rice system was calculated by transfer coefficients (TC Se) in this study. The results showed that Se transfer from soil to roots and from stems to grain were key steps for controlled Se concentration in rice grains. The multiple linear regression analysis makes an implication that some elements influence the Se transfer significantly: soil K and Hg may suppress Se entering rice roots; B, Cu, and Mo in rice root may restrain Se transfer from root to stem; and S, Cr, P, and Mg in rice stem had negative effects on Se accumulation in rice grain. Therefore, reducing heavy metal pollution and managing fertilizer amounts may elevate Se concentration in rice grain, especially when Se concentration in soils is low. [ABSTRACT FROM AUTHOR]

Objectives. The literature on "image of aging" suggests that exposure to positive portrayals of old age has positive downstream consequences for older adults. This study examined whether these positive consequences might have limits, such that they occurred for portrayals of old age that were positive, but not those that were extremely positive. Method. Younger and older adults were allowed to selectively view (Study 1) or were experimentally exposed to (Studies 2 and 3) portrayals of old age of different levels of positivity. Their attention (Study 1) and physiological responses (Study 2) toward the portrayals, as well as perception of personal aging (Study 1) and memory performance (Study 3) after the exposure, were assessed. Results. Findings from 3 studies suggested that older adults have a less negative perception of personal aging (Study 1) and a stronger calming physiological response (Study 2) when being exposed to portrayals of old age that were positive, but not extremely positive. Moreover, extremely positive portrayals lowered downstream memory performance (Study 3) and attracted less attention from older adults when they found these portrayals unrealistic (Study 1). Discussion. These findings pinpoint the conditions under which positive portrayals of old age may benefit older adults. [ABSTRACT FROM AUTHOR]

The Changjiang Delta Region is a rapidly urbanizing area in China. But this area still reveals different anthropogenic activities and urbanization levels. River sediments from urban, suburban, and rural areas were studied to characterize potentially harmful elements (PHEs) and their ecological risks. Chemical compositions of sediments were analyzed, which revealed pronounced differences in three areas. Al2O3, Fe2O3, CaO, and MgO were elevated in the urban sediments. Sediments from the rural area showed high organic matter. CaO and TOC of sediments fluctuated significantly in the suburban area. They are associated with the local geological provenance and sediment circumstance. The enrichments of PHEs in sediments of urban rivers were prevalent, among which Cd and As were prominent. Concentrations of PHEs in the suburban area fluctuated significantly. Lead and Cu were obviously enriched in this area. Rural sediments had relatively low concentrations of PHEs, which were also stable in the regional distribution, although As showed a slight enrichment. Based on RI values from Hakanson, the urban sediments showed moderate to considerable ecological risk. And the suburban sediments were in moderate ecological risk, except some high-risk samples. The majority of rural sediments revealed low ecological risk. Of these hazardous elements, Cd, Hg, and Pb contribute the largest proportion of the total ecological risk. It is evident that the urbanization level influences the distributions and contamination grades of PHEs for river sediments of the Changjiang Delta Region. [ABSTRACT FROM AUTHOR]

The axial flux permanent magnet (AFPM) machines with the parallel magnetic circuit (PMC) rotor can effectively improve its torque density. The PMC rotor consists of two sub‐rotors, radial Halbach array permanent magnet (PM) and tangential PM. The magnetic fields generated by two sub‐rotors are not in the same 2‐D analytical planes. In this paper, an equivalent analytical model of PMC‐AFPM machines is proposed to solve this problem. The radial Halbach array PM rotor is equated to the axial Halbach array PM rotor based on the equivalent transformation principle. The exact subdomain models of equivalent axial Halbach array PM rotor and tangential PM rotor are built respectively and then superimposed to obtain the magnetic field distribution. The electromagnetic characteristics of the PMC‐AFPM machine under no‐load and load conditions are calculated by the proposed analytical model and compared with calculations of the finite element model (FEM). The results verify the accuracy of the equivalent analytical model. The comparative analysis of the AFPM machines with PMC rotor and tangential PM rotor verifies the advantage of PMC rotor configuration to improve the torque density. © 2024 Institute of Electrical Engineer of Japan and Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

Future climate change can cause more days with poor air quality. This could trigger more alerts telling people to stay inside to protect themselves, with potential consequences for health and health equity. Here, we study the change in US air quality alerts over this century due to fine particulate matter (PM2.5), who they may affect, and how they may respond. We find air quality alerts increase by over 1 mo per year in the eastern United States by 2100 and quadruple on average. They predominantly affect areas with high Black populations and leakier homes, exacerbating existing inequalities and impacting those less able to adapt. Reducing emissions can offer significant annual health benefits ($5,400 per person) by mitigating the effect of climate change on air pollution and its associated risks of early death. Relying on people to adapt, instead, would require them to stay inside, with doors and windows closed, for an extra 142 d per year, at an average cost of $11,000 per person. It appears likelier, however, that people will achieve minimal protection without policy to increase adaptation rates. Boosting adaptation can offer net benefits, even alongside deep emission cuts. New adaptation policies could, for example: reduce adaptation costs; reduce infiltration and improve indoor air quality; increase awareness of alerts and adaptation; and provide measures for those working or living outdoors. Reducing emissions, conversely, lowers everyone's need to adapt, and protects those who cannot adapt. Equitably protecting human health from air pollution under climate change requires both mitigation and adaptation. [ABSTRACT FROM AUTHOR]

The electromagnetic vibration and noise level of ultra‐high‐speed bearingless permanent magnet synchronous motor (UBPMSM) for air compressors used in the fuel‐cell vehicle (FCV) is an important evaluation. A 10 kW, 100 k r/min UBPMSM is adopted as the object of study in this research. The expression of radial electromagnetic force of UBPMSM is derived through theoretical analysis, and the order and frequency characteristics of radial electromagnetic force harmonics are summarized. Through the two‐dimensional (2D) Fourier decomposition of radial electromagnetic force by finite element analysis (FEA), the main sources of radial electromagnetic force causing the electromagnetic vibration and noise are studied. The correctness of the mathematical model is verified by FEA. In addition, the three‐dimensional (3D) finite element model of the motor is established to calculate the radial modal, natural frequency, and electromagnetic vibration and noise of UBPMSM. The research shows that the spatial order of radial electromagnetic force of UBPMSM is kN and kN ± 1 (N = GCD [2p, Z], k = 1, 2, 3, ...), and the noise change of UBPMSM caused by the addition of suspension windings could be ignored compared with ordinary motor. It provides reference values for the design and optimization of UBPMSM. © 2022 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

Biochar and inorganic fertilizer when co‐applied have been reported to increase crop yield and enhance soil fertility. However, studies on this complementary effect on soil properties and noodle rice performance in China are still scanty. To investigate the effects of biochar application coupled with inorganic fertilizers on soil sustainability and yield and yield attributes of noodle rice, outdoor pot experiments were conducted in the early and late growing seasons in 2018. The treatment combinations were T1 (B0 t/ha + N270 kg/ha), T2 (B20 t/ha + N270 kg/ha), T3 (B40 t/ha + N270 kg/ha), T4 (B60 t/ha + N270 kg/ha), T5 (B0 t/ha + N360 kg/ha), T6 (B20 t/ha + N360 kg/ha), T7 (B40 t/ha + N360 kg/ha), and T8 (B60 t/ha + N360 kg/ha). The results compiled across the seasons showed an increase in Pn (net photosynthetic rate), grain yield, N uptake, gel consistency, amylose content (AC), and protein content in biochar‐treated pots as compared to T1. Average increases of 63.24, 63.66, 14.85, 58.0, 59.0, 22.39, and 2.9% were observed in soil porosity, moisture content, pH, organic carbon, total nitrogen, available phosphorus, and available potassium in T4 over T1 across the seasons, respectively. Root morphological characteristics such as total root length, surface area, volume, and average root diameter were significantly improved in T3, T4, T7, and T8. Starch‐related enzymes such as starch branching enzyme (SBE), starch debranching enzyme (DBE), and soluble starch synthase (SSS) were not affected significantly; however, granule‐bound starch synthase (GBSS), ADP‐glucose pyrophosphorylase (ADPG), and starch synthesis (SS) enzyme showed higher activity in 40 and 60 t B/ha across N rates. Conclusively, biochar application of 60 t/ha along with 270 kg N/ha is a promising option for improving soil quality and increasing photosynthesis, yield, and yield attributes of noodle rice. [ABSTRACT FROM AUTHOR]

1H-Indazoles are important heterocycles as they are a substantial part in many drugs. Here, a DBU-catalyzed aza-Michael reaction of indazole with enones is described. A variety of aromatic and aliphatic enones are well tolerated and afford the corresponding N1-substituted 1H-indazoles in high to excellent yields with exclusive N1-regioselectivity. The use of a metal-free catalyst, good substrate tolerance, mild reaction conditions, and high atom economy make this procedure a direct and facile method for the preparation of N1-substituted 1Hindazoles. [ABSTRACT FROM AUTHOR]

Optimal utilization of available water resources has become more urgent due to the rapid growth of the economy and population. The joint operation of the Three Gorges cascade and Qingjiang cascade reservoirs in China was studied in this paper. Choosing maximization of hydropower generation and hydropower revenue as objective functions respectively, optimal models were established for individual and joint operation of the cascade reservoirs. The models were solved by the progressive optimality algorithm. The storage and electric compensation benefits among cascade reservoirs were analyzed. The daily inflow data of consecutive hydrological years of 1982-1987 were selected for a case study. Compared with the design operation rule, the joint operation of the multi-reservoir system can generate 5.992 billion kWh of extra power or an increase of 5.70% by the objective function of maximum hydropower generation. Through reservoir storage compensation, the spilled water of the Three Gorges and Qingjiang cascade reservoirs was decreased by 78.741 and 5.384 billion m³, respectively. [ABSTRACT FROM AUTHOR]

Optimal utilization of available water resources has become more urgent due to the rapid growth of the economy and population. The joint operation of the Three Gorges cascade and Qingjiang cascade reservoirs in China was studied in this paper. Choosing maximization of hydropower generation and hydropower revenue as objective functions respectively, optimal models were established for individual and joint operation of the cascade reservoirs. The models were solved by the progressive optimality algorithm. The storage and electric compensation benefits among cascade reservoirs were analyzed. The daily inflow data of consecutive hydrological years of 1982-1987 were selected for a case study. Compared with the design operation rule, the joint operation of the multi-reservoir system can generate 5.992 billion kWh of extra power or an increase of 5.70% by the objective function of maximum hydropower generation. Through reservoir storage compensation, the spilled water of the Three Gorges and Qingjiang cascade reservoirs was decreased by 78.741 and 5.384 billion m3, respectively. [ABSTRACT FROM AUTHOR]

Abstract: Recent applications of 3D virtual imaging techniques in human palaeontology have increased the possibilities and the accuracy of anthropological analysis. Two examples are given for the reconsideration of fossils discovered more than 20years ago, thanks to this new technology. The Lower and Middle Pleistocene skulls from Yunxian and Nankin in China, which were damaged in the process of fossilization, have been virtually reconstructed. A detailed reinvestigation has been conducted by considering those reconstructed skulls and their unpublished characters (i.e., inner anatomical features inaccessible until now). The results of this analysis provide new information about the early hominids of China and contribute to the discussion of variability in Homo erectus. [ABSTRACT FROM AUTHOR]

There is some debate concerning whether people selectively attend to and remember less negative relative to positive or neutral information with age. We argue that such an age-related negativity reduction effect may be attenuated among individuals who are more interdependent, as they are likely to perceive negative information as equally useful and important as positive information. In 2 studies, we tested this hypothesis by examining memory for (Study I) and visual attention to (Study 2) emotional (positive vs. negative) stimuli among younger, middle-aged, and older Chinese participants. Findings revealed that the age-related negativity reduction effect was found to a lesser extent among older Chinese individuals who were more interdependent than among those who were less interdependent. [ABSTRACT FROM AUTHOR]