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Electrocatalytic methods are valuable tools for addressing water pollution and scarcity, offering effective pollutant removal and resource recovery. To investigate the current status and future trends of electrocatalysis in wastewater treatment, a detailed analysis of 9417 papers and 4061 patents was conducted using scientometric methods. China emerged as the leading contributor to publications, and collaborations between China and the USA have emerged as the most frequent partnerships. Primary article co-citation clusters focused on oxygen evolution reaction and electrochemical oxidation, transitioning towards advanced oxidation processes ("persulfate activation"), and electrocatalytic reduction processes ("nitrate reduction"). Bifunctional catalysts, theoretical calculations, electrocatalytic combination technologies, and emerging contaminants were identified as current research hotspots. Patent analysis revealed seven types of electrochemical technologies, which were compared using SWOT analysis, highlighting electrochemical oxidation as prominent. The technological evolution presented the pathway of electro-Fenton to combined electrocatalytic technologies with biochemical processes, and finally to coupling with electrocoagulation. Standardized evaluation systems, waste resource utilization, and energy conservation were important directions of innovation in electrocatalytic technologies. Overall, this study provided a reference for researchers to understand the framework of electrocatalysis in wastewater treatment and also shed light on potential avenues for further innovation in the field. [ABSTRACT FROM AUTHOR]

Dust events frequently occur in Tarim Basin (TB), China. However, research is scarce on the variation characteristics of sand-dust, floating-dust, sand-blowing, and sandstorms in the mountains, oases, and deserts in TB. Therefore, we conducted in-depth studies on the distributions and variations of dust events in TB. The results indicate that dust events tend to increase from south to north. The yearly sand-dust event occurrence rate trend is deserts > oases > mountainous regions. Spring events of sand-dust, floating-dust, sand-blowing, and sandstorms account for 35.9%, 36.0%, 38.5%, and 47.1% and summer events for 33.6%, 33.5%, 43.8%, and 60.3% of the total annual average sand-dust, floating-dust, sand-blowing, and sandstorm days, respectively. From 1961 to 2015, most stations (annual average > 30 stations) showed a downward linear trend in sand-dust, floating-dust, sand-blowing, and sandstorms in TB. All types of sand-dust events in mountains and oases decreased substantially after 1975–1978. In spring and summer, the downward dust trends are the most obvious, which the largest annual average downward linear trend rates of floating-dust, sand-blowing, and sandstorms are − 0.33 d/yr (QM station), − 0.21 d/yr (TGLK station), and − 11 d/yr (KP station), respectively, in spring, and − 0.28 d/yr (QM station), − 0.17 d/yr (TGLK station), and − 0.14 d/yr (KP station), respectively, in summer. It is found that the decreasing and increasing trends of floating-dust are the most frequent among sand-dust events. There are a significant positive correlation between wind speed and relative humidity in mountains and a significant positive correlation between wind speed in oases. [ABSTRACT FROM AUTHOR]

The composition of air pollutants and features of the near–ground layer were investigated from four 100 m high towers during a heavy pollution event in 2013 in Urumqi, northwest China. The PM2.5, PM10, SO2, NO2, and CO concentrations increased rapidly during the heavy pollution event, with the exact amounts dependent on air pollutant emissions and meteorological conditions. Ozone concentrations increased in northern rural areas, and were affected by the emission and conversion of primary pollutants from urban areas. The maximal mixing layer was slightly lower than 1000 m. A strong temperature inversion intensity of 6.8, 2.5, 4.2, and 4.7 °C/100 m in suburban, urban, northern suburban, and rural sites, respectively, occurred during the heavy pollution event. A significant mountain–valley wind in the urban and northern suburbs was an important factor affecting the heavy pollution. During heavy pollution days, the wind was almost always from the south and east, and the wind speed was mostly over 7 m·s−1 in the southern suburbs. Conversely, it was lower than 2 m s−1 in the urban and northern rural sites, where the wind directions were variable. There was a positive correlation between pollutant concentrations and air temperature, but pollutant concentrations were negatively correlated with relatively humidity. Dynamic and thermal turbulence (friction velocity and vertical kinematic eddy heat flux) favored the diffusion and accumulation of heavy pollution in Urumqi. The friction velocity was strong in the southern suburbs (0.5 m s−1), but was weak at the northern rural (0.11 m s−1) site, which were located on high and low terrain, respectively. The turbulent thermal effect was the main atmospheric condition associated with the formation of heavy pollution events, which had little relationship with the turbulent dynamic effect. A backward trajectory analysis of the atmospheric motion showed that heavy pollution events were more likely to be caused by local pollutant transport. [ABSTRACT FROM AUTHOR]

The leaf area index (LAI) is a crucial parameter for analyzing terrestrial ecosystem carbon cycles and global climate change. Obtaining high spatiotemporal resolution forest stand vegetation LAI products over large areas is essential for an accurate understanding of forest ecosystems. This study takes the northwestern part of the Inner Mongolia Autonomous Region (the northern section of the Greater Khingan Mountains) in northern China as the research area. It also generates the LAI time series product of the 8-day and 30 m forest stand vegetation growth period from 2013 to 2017 (from the 121st to the 305th day of each year). The Simulated Annealing-Back Propagation Neural Network (SA-BPNN) model was used to estimate LAI from Landsat8 OLI, and the multi-period GaoFen-1 WideField-View satellite images (GF-1 WFV) and the spatiotemporal adaptive reflectance fusion mode (STARFM) was used to predict high spatiotemporal resolution LAI by combining inversion LAI and Global LAnd Surface Satellite-derived vegetation LAI (GLASS LAI) products. The results showed the following: (1) The SA-BPNN estimation model has relatively high accuracy, with R2 = 0.75 and RMSE = 0.38 for the 2013 LAI estimation model, and R2 = 0.74 and RMSE = 0.17 for the 2016 LAI estimation model. (2) The fused 30 m LAI product has a good correlation with the LAI verification of the measured sample site (R2 = 0.8775) and a high similarity with the GLASS LAI product. (3) The fused 30 m LAI product has a high similarity with the GLASS LAI product, and compared with the GLASS LAI interannual trend line, it accords with the growth trend of plants in the seasons. This study provides a theoretical and technical reference for forest stand vegetation growth period LAI spatiotemporal fusion research based on high-score data, and has an important role in exploring vegetation primary productivity and carbon cycle changes in the future. [ABSTRACT FROM AUTHOR]

The frequent detection of persistent per- and polyfluoroalkyl substances (PFAS) in organisms and environment coupled with surging evidence for potential detrimental impacts, have attracted widespread attention throughout the world. In order to reveal research hotspots and trends of technologies for PFAS removal, herein, we performed a data-driven analysis of 3975 papers and 436 patents from Web of Science Core Collection and Derwent Innovation Index databases up to 2023. The results showed that China and the USA led the way in the research of PFAS removal with outstanding contributions to publications. The progression generally transitioned from accidental discovery of decomposition, to experimentation with removal effects and mechanisms of existing methods, and finally to enhanced defluorination and mechanism-driven design approaches. The keywords co-occurrence network and technology classification together revealed the main knowledge framework, which was constructed and correlated through contaminants, substrates, materials, processes and properties. Moreover, adsorption was demonstrated to be the dominant removal process among the current studies. Subsequently, we concluded the principles, advances and drawbacks of enrichment and separation, biological methods, advanced oxidation and reduction processes. Further exploration indicated the hotspots such as alternatives and precursors for PFAS ("genx": 1.258, "f-53b": 0.337), degradable mineralization technologies ("photocatalytic degrad": 0.529, "hydrated electron": 0.374), environment-friendly remediation technologies ("phytoremedi": 0.939, "constructed wetland": 0.462) and combination with novel materials ("metal-organic framework": 1.115, "layered double hydroxid": 0.559) as well as computer science ("molecular dynamics simul": 0.559, "machine learn"). Furthermore, the future direction of technological innovation might lie in high-performance processes that minimize secondary pollution, the development of recyclable and renewable treatment agents, and collaborative control strategies for multiple pollutants. Overall, this study offers comprehensive and objective review for researchers and industry professionals in this field, enabling rapid access to knowledge guidance and insights into research frontiers. [Display omitted] [ABSTRACT FROM AUTHOR]

As the largest fixed and semi‐fixed desert in China, the Gurbantünggüt Desert undergoes a long period of snow cover in the winter and the rapid growth of ephemeral plants in the spring, presenting obvious seasonal changes in the underlying desert surface type, which can lead to variation in the turbulence of the near‐surface boundary layer turbulence over the desert. In this study, gradient tower data and eddy covariance data from 2017 were analysed to investigate the turbulence characteristics of the different surface boundary layers in the hinterland of the Gurbantünggüt Desert. The results indicate that stable atmospheric conditions in the desert occur exclusively during the early morning and at night in the desert, and the onset and duration of this stable state varies seasonally. Two regimes of intermittent turbulence occur during the night, a weak turbulent regime that occurs when the wind speed is less than the threshold and a strong turbulent regime when the wind speed exceeds the threshold, and different wind speed thresholds were observed at each level. These parameters follow a seasonal pattern of summer (July) > spring (April) > autumn (October) > winter (January) in terms of magnitude. The mean turbulence intensities of the along‐wind, cross‐wind and vertical wind are 0.5, 0.47 and 0.14, respectively, with Iu > Iv > Iw. The normalized standard deviation of the wind velocity components (σu, σv and σw) generally satisfies a 1/3 power‐law relation. Our results show that the night‐time turbulence regime classification for the Gurbantünggüt Desert strongly depends on meteorological and orographic features, and the intermittent turbulent events have the non‐stationarity of the flow in common. The results can contribute to the study of land surface processes, climate change and desertification in inland arid desert areas. [ABSTRACT FROM AUTHOR]

The nocturnal oasis cold island (OCI) effect is an important phenomenon seen over the heterogeneous surfaces of oases and deserts in northwest China and is influenced by many unknown complex factors. Using field observations and wind profile radar data over oases and deserts in Zhangye city, China, we analyze the relationship between the OCI effect and the low-level jet (LLJ). Vertical mixing induced by the LLJ has a profound impact on the intensity of the OCI effect during the night. The mean nocturnal intensity of the OCI effect and the strength of the nocturnal LLJ are significantly correlated. We investigate two examples in detail—one with a strong OCI effect and one with a weak OCI effect—using observational data and simulations by the Weather Research and Forecasting model. During a weak LLJ, when the wind speed decreases and vertical mixing is weakened, the increase in evaporation over the oasis causes the temperature to decrease dramatically and results in a strong OCI effect. During a strong LLJ, the strong shear induced below the nose of the LLJ enhances turbulent mixing, heat is transported downward, and the temperature over the oasis decreases slightly. The near-surface wind speed over the desert increases, and the decrease in temperature is larger than that during a weak LLJ. Therefore, the intensity of the OCI effect decreases during a strong LLJ. [ABSTRACT FROM AUTHOR]

Over the hinterland of the Taklimakan Desert (TD), the diurnal and seasonal cycles of the air temperature (AT) and horizontal sand-dust flux (HSDF) were investigated, based on in situ data including sand saltation counts and meteorological parameters in the period 2008–2010. In particular, the relationship between AT and HSDF was determined. It was found that 74.7% of HSDF was observed between 10:00 and 20:00, and HSDF in spring and summer accounted for 92.3% of the annual flux. Further, the diurnal and annual cycles of HSDF and AT presented an exponential distribution, with correlation coefficients (R) of 0.97 and 0.93, respectively. Additionally, when AT was 0 °C or lower, the frequency of sand saltation was only 4.3%. The maximum sand saltation frequency was 70.1%, which occurred at 33–34 °C, while 67.6% of the total HSDF occurred at 24–34 °C. Finally, a Gauss equation was established over the TD: Q = 250.2 + 1368.5e−2 × [(T−30.8)/7.3]^2, with R = 0.90. Results revealed a strong correlation between HSDF and AT, indicating that AT should be noticeable in HSDF parameterization schemes. [ABSTRACT FROM AUTHOR]

Sulfur-containing organic pollutants and their derivatives are ubiquitously present in aquatic ecosystems. Their elevated environmental risk profiles have increasingly brought them to the forefront of scholarly attention. In light of this, the present study offered a comprehensive review of the developmental trajectory, current status, and future prospects of sulfur-containing organic wastewater treatment, as deduced from bibliometric and patent analyses. Post-2005 witnessed a marked surge in research publications, with China and the US spearheading this academic thrust, boasting the highest publication counts. Furthermore, collaborations saw a significant tilt towards partnerships involving China, the US, and Germany with international counterparts. The most prevalent 100 keywords, discerned from publications, coalesced around four pivotal domains: pollutants, technological advancements, chemical constituents, and detection methodologies. An emergent trend identified an uptick in the frequencies of terms such as "Sulfur-Oxidizing-Bacteria" and "Electrochemical Oxidation". From the technology innovation perspective, China's patent submissions constituted approximately two-thirds of the global filings. Technologies anchored in Advanced Oxidation Processes (AOPs) and biodegradation held prominence, while membrane separation techniques, high-efficacy and recyclable catalysts, and cost-efficient procedures for addressing sulfur-containing wastewater were spotlighted as promising avenues, as inferred from the patent-based knowledge gap analysis. [Display omitted] • Swift progression in studies on sulfur-based organic contaminants. • A critical assessment of 5079 articles and 5763 patents. • Knowledge cartography illuminated sulfuric organic wastewater treatments. • AOPs and biodegradation emerge as quintessential technologies. • Membrane separation and recyclable catalysts exhibit vast potentialities. [ABSTRACT FROM AUTHOR]

In order to reveal the status and trends of chemical treatment for wastewater, the patents analysis from both structured and unstructured data was performed in this study. 35,838 patents recorded in the Derwent Innovation Index database were adopted. The results showed that China was the country with the largest number of patents in the field, and the United States was the main exporter of international technology flows. Chemical processes combined with biological and physical processes was the mainstream, and ozonation and electrochemical treatment were the major single technologies. Technology evolution path generally showed the transition from biological process-combined chemical treatment to electrochemical treatment and finally to physical process-combined chemical treatment. Furthermore, future trends were revealed from both patents and papers. It demonstrated that efficient removal of ammonia nitrogen, green water treatment agents and resourcezation of wastewater were the key innovation directions, and technologies with regard to efficient use of energy (including photocatalytic technology and microbial fuel cell) were the main research hotspots. Overall, this study provided a comprehensive understanding for the research and application of chemical treatment for wastewater technologies. [Display omitted] • 35,838 patents on chemical treatment for wastewater were analyzed. • Patent analysis from both structured and unstructured data. • Chemical process combined with biological and physical processes was the mainstream. • Technology evolution path was elucidated in three stages. • Future trends were revealed from both patents and papers. [ABSTRACT FROM AUTHOR]

Field observations made with unmanned aerial vehicles of the particulate matter (PM) concentration from the ground to a height of 500 m were conducted at Xiaotang and Tazhong in the Taklimakan Desert (TD), China, from 7 to 15 November 2019. The vertical structures of the PM concentrations were studied. Pulsed lidar observations showed that dust aerosols in the TD can reach heights of 4 km. Within 500 m above the ground, the PM1.0, PM2.5, and PM10 concentrations were <100, <201, and <764 µg∙m−3, respectively, in the TD. On days containing sand-blowing periods (e.g., at 18:00 on 11 November), the PM1.0, PM2.5, and PM10 concentrations were 10–17.7 times higher than on clear days. The northern margin of the TD (Xiaotang) was dominated by fine particles, while the hinterland (Tazhong) was dominated by coarse particles, because there was sparse vegetation around Xiaotang and the surface was sand and clay, while there was no vegetation around Tazhong and the surface was sand. During floating dust periods, the boundary layer was dominated by fine particles. The average PM1.0/PM2.5 ratios were 0.25–0.65 and 0.40–0.80 at Tazhong and Xiaotang, respectively, while, during sand blowing periods, these ratios were 0.40–0.55 and 0.40–0.45, respectively. The critical condition in the atmospheric boundary layer for PM concentration was revealed with the enhanced momentum flux and sensible heat flux up to 0.52 kg∙m−1∙s−2, 0.69 m∙s−1, and 6.7 W∙m2, respectively, and the low mixed layer was high in the lower atmosphere. [ABSTRACT FROM AUTHOR]

Ethnopharmacological relevance Shenmai injection (SMI) is a traditional Chinese herbal medicine extracted from Panax ginseng ( Panax ginseng C.A. Mey, steamed and dry) and Ophiopogon japonicus ( Ophiopogon japonicus (L.f.) Ker-Gawl, root). It has been widely used for the treatment of chronic heart failure (CHF) in China. However, the evidence supporting its effects remains unclear due to lack of high quality trials. The aim of this study was to investigate the efficacy and safety of SMI in CHF patients with coronary artery disease (CAD). Materials and methods This double-blind, multicenter study randomized 240 eligible patients equally to receive SMI or placebo (100 ml/day) in addition to standard medicines for the treatment of CHF. The primary endpoint was the New York Heart Association (NYHA) functional classification. The secondary endpoints were 6-min walking distance (6MWD), short-form 36 (SF-36) hearth survey score, traditional Chinese medicines (TCM) syndrome score, left ventricular ejection fractions (LVEF) and B-type natriuretic peptide (BNP) level. Results During treatment of 1 week, the NYHA functional classification was gradually improved in both groups, but the SMI group demonstrated a significantly greater improvement compared with the placebo group ( p =0.001). Moreover, the improvement in patients received SMI was superior to those in control group with respect to 6MWD, SF-36 score and TCM syndrome score. Treatment with SMI within 1 week was well tolerated with no apparent safety concerns. Conclusions The integrative treatment with standard medicines plus SMI can further improve NYHA functional classification for patients with CHF and CAD. Therefore, SMI could be recommended in the combination therapy for CHF accompanied with CAD. [ABSTRACT FROM AUTHOR]