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Deprotection of amides is a virtually universal transformation in organic synthesis, often employing traditional active reductants such as SmI2, hydrosilanes, hydroboranes or H2 under high-pressure. Herein, we describe a green and sustainable electrocatalytic hydrolysis of amides utilizing water as the hydrogen source, thereby ideally avoiding the use of high-pressure and flammable hydrogen gas or other toxic and costly hydrogen donors. Our methodology utilized green electrons as reductants, facilitating highly selective and efficient electrocatalytic C–N hydrolysis of amides. This environmentally friendly electrochemical approach can also be successfully applied to the C–N hydrolysis of carbamates, formamides, and thioamides. Furthermore, this method extends to the dissociation of O–N and N–N bonds, exhibiting a wide scope and high functional group tolerance. Preliminary mechanistic studies support a proposed mechanism involving the electroreductive conversion of the carbonyl group into a hemiaminal intermediate, which subsequently collapses to yield free amines. [ABSTRACT FROM AUTHOR]

In this paper, we propose a new hybrid stress quadrilateral finite element method AGQ-LQg for the two-dimensional linear elasticity problems by using the area coordinates. In this method, a 4-node generalized conforming element with internal displacements for the displacement approximation and a 9-parameter linear stress mode for the stress approximation are adopted based on the generalized Hell- inger-Reissner variational principle. Numerical experiments show that the method is insensitive to mesh distortion. Meanwhile, it is also shown that this method can keep high precision even under coarse mesh and avoid the so-called Poisson-locking phenomenon effectively. [ABSTRACT FROM AUTHOR]

Catalyst-free, direct electrooxidative phenol derivatives C(sp3)–H mono- and di-alkylation reaction have been developed. In contrast to previous typical oxidative and electrochemical coupling, this electrosynthetic approach enables selective mono- and di-alkylations through metal- and external oxidant-free mild conditions via easily available electrodes. Advances of this strategy were proven by an unparalleled broad substrate scope for efficient C–C, C–N, C–O bond formation as well as excellent site- and regioselectivity. The electrochemical selective alkylations were devoid of additional electrolytes, could be conducted on a gram scale, and provided the enone products by cascade electrooxidative dehydrogenation, which highlight a notable potential for further late-stage diversification. Detailed mechanistic studies allowed to delineate the exact profile of the generation of the mono- and di-alkylation events. [ABSTRACT FROM AUTHOR]

Herein, we describe an innovative approach to the asymmetric electrochemical α-alkylation of aldehydes facilitated by a newly designed bifunctional chiral electrocatalyst. The highly efficient bifunctional chiral electrocatalyst combines a chiral aminocatalyst with a redox mediator. It plays a dual role as a redox mediator for electrooxidation, while simultaneously providing remarkable asymmetric induction for the stereoselective α-alkylation of aldehydes. Additionally, this novel catalyst exhibits enhanced catalytic activity and excellent stereoselective control comparable to conventional catalytic systems. As a result, this strategy provides a new avenue for versatile asymmetric electrochemistry. The electrooxidation of diverse phenols enables the C-H/C-H oxidative α-alkylation of aldehydes in a highly chemo- and stereoselective fashion. Detailed mechanistic studies by control experiments and cyclic voltammetry analysis demonstrate possible reaction pathways and the origin of enantio-induction., (© 2024 Wiley‐VCH GmbH.)

It is of great practical significance to identify service blind area, scientifically select park construction areas, and clarify the priority of parks' construction based on the co-ordination of supply-demand evaluation. With the urban parks within the Taiyuan Ring Expressway as the research subjects, we estimated the accessibility range and the service pressure of each park by using the application programming interface of Gaode map route planning and point of interest data to characterize their supply and demand levels. We identified the service blind areas of parks by overlay analysis, and used the location-allocation (LA) model to purposefully supply park green space. Results showed that the accessibility coverage rates of the parks by walking and bicycling within 15 minutes were 35.6% and 71.7%, respectively, indicating insufficient supply capacity of parks. The areas with large potential demand for park green space in Taiyuan were mainly concentrated in the business district of Qinxian-Changfeng Street and the Shuangta business district within Dongzhong ring road, which existed the obviously invisible blind areas. Finally, we proposed new park green space site selection proposal based on LA model. Optimization results indicated that the coverage rates of walking and bicycling within 15 minutes increased to 46.7% and 81.0%, respectively, and that the service pressure of parks was relieved. We combined the leisure demands of urban residents and the distribution of urban parks by utilizing network big data, which could promote the scientific nature and accuracy of the optimizing site selection and provide scientific method and theory basis for urban park construction.

PM 2.5 and ozone co-pollution, which are harmful to not only human health but also the social economy, has become the pivotal issue in air pollution prevention and synergistic control, especially in Beijing-Tianjin-Hebei and its surrounding areas and "2+26" cities. It is necessary to analyze the correlation between PM 2.5 and ozone concentration and explore the mechanism of PM 2.5 and ozone co-pollution. In order to study the characteristics of PM 2.5 and ozone co-pollution in Beijing-Tianjin-Hebei with its surrounding area, ArcGIS and SPSS software were used to analyze the correlation between air quality data and meteorological data of the "2+26" cities in Beijing-Tianjin-Hebei and its surrounding areas from 2015 to 2021. The results indicated:① PM 2.5 pollution constantly decreased from 2015 to 2021, and the pollution was concentrated in the central and southern parts of the region; ozone pollution showed a trend of fluctuation and presented a pattern of "low in the southwest and high in the northeast" spatially. In terms of seasonal variation, PM 2.5 concentration was mainly in the order of winter>spring ≈ autumn>summer, and O 3 -8h concentration was in the order of summer>spring>autumn>winter. ② In the research area, days with PM 2.5 exceeding the standard continued to decline, whereas days with ozone exceeding the standard fluctuated, and days with co-pollution decreased significantly; there was a strong positive correlation between PM 2.5 and ozone concentration in summer, with the highest correlation coefficient of 0.52, and a strong negative correlation in winter. ③ Comparing the meteorological conditions of typical cities during the ozone pollution period with that of the co-pollution period, the co-pollution occurred under the temperature range of 23.7-26.5℃, humidity of 48%-65%, and S-SE wind direction.

Reports of decreasing PM 2.5 concentrations in some developed countries and regions, as well as the trends of annual average concentrations of PM 2.5 in the 74 key cities of China from 2013 to 2016 were analyzed. The cities were categorized based on PM 2.5 concentration ranges and the regions where they are located. The average annual declining rates of PM 2.5 concentration were calculated for these categories. Based on previous PM 2.5 rates, we proposed different scenarios of decreasing PM 2.5 concentration in Chinese cities for the future decades. Future PM 2.5 concentration was calculated for each of the Chinese cities, and the milestones for 31 provinces and key areas were analyzed. The results showed that the annual average concentration of PM 2.5 in China could meet the national air quality standard by 2025 and drop below 30 μg·m -3 in 2030 under both scenarios. The PM 2.5 concentration in Beijing-Tianjin-Hebei and surrounding areas could meet the standards in 2030, and the Yangtze River Delta area in 2025. It will be difficult for Beijing, Tianjin, Hebei, and Henan to meet the standard in 2030. Even in the scenario where measures were intensified in the key areas, the cities failed to meet the PM 2.5 concentration standards. In Beijing-Tianjin-Hebei and surrounding areas, the values were close to 40% of the target by 2030. To accelerate the reduction of PM 2.5 concentration, extreme efforts will be needed in the highly polluted areas.

To investigate the characteristics of PM 2.5 emissions in Anyang, the PM 2.5 emission inventory from industrial sources of Anyang in 2016 was established based on reasonable estimation method and emission factor. The spatial distribution analysis was carried out using Geographic Information System (GIS) technology. Based on the industry's typical ultra-low emission transformation and coal pressure reduction requirements, three scenarios were set to estimate the PM 2.5 emission reduction potential of industrial sources from Anyang in 2020. The results show that the total PM 2.5 emissions from industrial sources in Anyang was 81071.13 t in 2016. Non-ferrous metallurgy, iron and steel, and building materials industries were the main contributing sources, accounting for 45.43%, 25.74%, and 18.00% of the total emissions, respectively. The emission differences between towns and within Anyang were outstanding. The PM 2.5 emissions were mainly concentrated in urban areas, Linzhou City, and Anyang County. The emissions in Anyang City were most prominent, while the emission intensity differences between the four jurisdictions of Anyang City were even greater. In the three different control scenarios, the potential for PM 2.5 emission reduction in Anyang in 2020 was estimated to be 398.72, 11623.87, and 14072.27 t, accounting for 0.49%, 14.34%, and 17.22% of the total industrial source emissions in 2016, respectively. It can be concluded that Anyang has a great potential for PM 2.5 emission reduction. In addition, ultra-low emission reform and coal pressure reduction can be of great significance for PM 2.5 emission reduction in Anyang.

Objective: To observe the effects of navel-warming therapy on clinical efficacy in patients with yang-deficiency tympanites based on regular treatment of western medication., Methods: One hundred and twenty cases of yang-deficiency tympanites were randomly divided into a navel-warming therapy group and a western medication group, sixty cases in each one. The regular treatment of western medicine was applied in the western medication group, including oral administration of antiviral drug and diuretics as well as intravenous drip of hepatic protector. Based on western medicine treatment, the navel-warming therapy was applied in the navel-warming group. A medical cake was laid on Shenque (CV 8), and then a medical cylinder was placed above the medical cake and ignited. The treatment was given once daily. One month was considered as a treatment session in both groups and totally one session was required. The TCM symptom score, B-ultrasound ascites and temporary use of diuretics before and after treatment were observed in both groups; also the efficacy was evaluated., Results: The total effective rate was 81.7% (49/60) in the navel-warming therapy group, which was superior to 56.7% (34/60) in the western medication group (P < 0.05). After the treatment, the TCM symptom score and ascites were improved in both groups (all P < 0.05), which was more significant in the navel-warming therapy group (all P < 0.05). The temporary use of diuretics was statistically different between the two groups (P < 0.05), indicating the navel-warming therapy group could obviously reduce or stop the use of diuretics., Conclusion: Based on regular treatment of western medication, the navel-warming therapy could significantly improve therapeutic efficacy, effectively relieve clinical symptoms and ease ascites.

To develop a new pattern of air pollution control that is based on the integration of "concentration control, total amount control, and quality control", and in the context of developing national (2011-2015 air pollution control plan for key areas) and (Environmental protection plan of Zibo municipality for the "12th Five-Year Plan" period), a simulation of atmospheric dispersion of air pollutants in Zibo City and its peripheral areas is carried out by employing CALPUFF model, and the atmospheric environmental capacity of SO2, NO(x) and PM10 is estimated based on the results of model simulation and using multi-objective linear programming optimization. The results indicates that the air pollution in Zibo City is significantly related to the pollution sources outside of Zibo City, which contributes to the annual average concentration of SO2, NO2 and PM10 in Zibo City by 26.34%, 21.23%, and 14.58% respectively. There is a notable interaction between districts and counties of Zibo municipality, in which the contribution of SO2, NO(x) and PM10 emissions in surrounding counties and districts to the annual average concentrations of SO2, NO2 and PM10 in downtown area are 35.96%, 43.17%, and 17.69% respectively. There is a great variation in spatial sensitivity of air pollutant emission, and the environmental impact of unit pollutant emissions from Zhoucun, Huantai, Zhangdian and Zichuan is greater than that released from other districts/counties. To meet the requirement of (Ambient air quality standard) (GB 3095-2012), the environmental capacities of SO2, NO(x) and PM10 of Zibo City are only 8.03 x 10(4) t, 19.16 x 10(4) t and 3.21 x 10(4) t, respectively. Therefore, it is imperative to implement regional air pollution joint control in Shandong peninsula in order to ensure the achievement of air quality standard in Zibo City.

This study selected 90 samples from different brands of red wine. In order to eliminate the impact of spectral curve's baseline, the first derivatives of all of spectral curves were calculated and the principal component analysis was carried out on the first derivative spectra. The result showed that the contribution rate of the first two principal components was over 80 percent. By the first two principal components, all the red wine samples were obviously divided into two classes. Furthermore a 3-layer artificial neural network predictive model was built with the first four principal components as input variables and 100 percent correct prediction rate was gained. The research showed that the visible-near infrared spectroscopy combined with principal component analysis provides an accurate and reliable new method to rapidly and nondestructively recognize the true or false red wines.