[Characteristics and Source Apportionment of Carbonaceous Aerosols in the Typical Urban Areas in Chongqing During Winter].

To investigate the characteristics, source apportionment, and potential source areas of carbonaceous aerosols in Chongqing during winter, PM2.5 samples were collected from January 2021 to February 2021 in the urban areas of Wanzhou (WZ), Yubei (YB), and Shuangqiao (SQ). The results showed that the average mass concentrations of PM2.5, OC, and EC in SQ were (72.6 ±33.3), (18.2 ±8.2), and (4.4 ±1.7) µg·m-3, respectively, higher than those in WZ[(67.2 ±30.3), (17.2 ±7.4), and (5.1 ±2.4) µg·m-3] and YB[(63.4 ±25.7), (15.4 ±6.3), and (4.2 ±1.9) µg·m-3]. Compared with that during the clear period, the concentration and fraction of EC in total carbon increased by 103.0% and 8.1%, respectively, in WZ compared to that in other areas during pollution period, whereas the OC/EC ratio was decreased significantly (-10.5%), indicating that the primary emission of carbonaceous aerosols increased significantly during the pollution period. The average mass concentrations of secondary organic carbon (SOC) in SQ and YB were (7.7 ±4.8) µg·m-3 and (6.9 ±2.8) µg·m-3 significantly higher, respectively, than that in WZ[(4.5 ±1.9) µg·m-3] during the campaign. This indicated that the secondary transformation had a greater influence on the carbonaceous aerosols in SQ and YB than that in WZ. Furthermore, in contrast to that in WZ, the ratios of SOC/OC were increased with the increase in PM2.5 concentrations, and significant correlations between SOC concentration and aerosol water content, NO2 concentration, and the value of NOR were observed in SQ and YB (P < 0.01), indicating that the increasing of carbonaceous aerosol concentrations might be mainly driven by the SOC with -NO2 groups produced by aqueous chemical reactions during winter in SQ and YB. The positive definite matrix factor (PMF) results in these urban areas showed that the contribution of biomass/coal combustion source in WZ (47.4%) was significantly higher than that in YB (34.2%) and SQ (38.1%), whereas the gasoline motor vehicle emission and secondary transformation impacts were more significant in YB. The results of the concentration weighted trajectory (CWT) showed that the potential sources of carbonaceous aerosols were mainly the local and northeastern parts of these urban areas (such as Changshou).

Patient satisfaction with humanistic nursing in Chinese secondary and tertiary public hospitals: a cross-sectional survey.

Background: Humanistic care pertains to the abilities, attitudes, and behaviors central to patient-centered care, contributing to patients' sense of safety and wellbeing. This study aimed to assess the satisfaction of patients with humanistic nursing care in Chinese secondary and tertiary public hospitals. Methods: A national cross-sectional survey was conducted across 30 provinces and 83 hospitals in China. Patient satisfaction with humanistic care was assessed using the Methodist Health Care System Nurse Caring Instrument (NCI), which encompasses 20 items across 12 dimensions. Each item was rated on a 7-point Likert scale, yielding a total score of 140. Multiple linear regression analysis was employed to identify factors associated with patients' satisfaction. Results: Moderate satisfaction (mean score 91.26 ± 13.14) with humanistic nursing care was observed among the 17,593 participants. Factors significantly associated with patient satisfaction included age, hospital type, presence of children, educational attainment, place of residence, family monthly income, and medical insurance type. Conclusion: The study findings highlight the importance of tailored interventions, evidence-based practice guidelines, and patient-centered care in improving patients' satisfaction with humanistic nursing care. Continuous emphasis on nursing education and professional development is crucial for enhancing humanistic care and patient satisfaction.

[Sources Apportionment of Oxygenated Volatile Organic Compounds (OVOCs) in a Typical Southwestern Region in China During Summer].

Oxygenated volatile organic compounds (OVOCs) are important intermediates in the troposphere and the most important sources of ozone. Proton-transfer-reaction time-of-flight mass spectrometry (PTR-TOF-MS) was used to measure VOCs in the Chengdu Plain, Southwestern China. The diurnal variations, photochemical reactivity, O3 formation potential, and sources were also investigated. The mixing ratios of ten kinds of VOCs (acetaldehyde, acetone, isoprene, Methyl ethyl ketone, Methyl vinyl ketone and Methacrolein, benzene, toluene, styrene, C8 aromatics, and C9 aromatics) were (10.97±4.69)×10-9. The concentrations of OVOCs, aromatic hydrocarbons, and biogenic VOCs were (8.54±3.44)×10-9, (1.53±0.93)×10-9, and (0.90±0.32)×10-9, respectively. Isoprene, acetaldehyde, and m-xylene were the top three photochemically active species with the greatest O3 formation potentials. The dominant three OVOCs species (acetaldehyde, acetone, and MEK) were mainly derived from local biogenic sources and anthropogenic secondary sources, and acetone had a strong regional background level, indicating that pollution in this area is significantly affected by regional transmission. This study deepens the understanding of regional O3 formation mechanisms in southwest China and provides a basis for the scientifically informed control of O3 pollution.

[Characteristics of Atmospheric Dry and Wet Deposition of Trace Metals in the Hinterland of the Three Gorges Reservoir, China].

In order to investigate the characteristics of atmospheric trace metals deposition in the hinterland of the Three Gorges Reservoir, the wet and dry deposition samples were collected at an urban area sampling site in Wanzhou during January to June 2014. Besides, the samples were collected at five other sampling sites in April 2014 for comparative analysis, including factory region, town suburb, nature reserve, county suburb, and rural area. pH, conductivity, and trace metals (Al, As, B, Ba, Bi, Cd, Co, Cr, Cu, Fe, Li, Mn, Pb, Ni, Sb, Sr, Sn, Ti, Zn, V) were analyzed. In urban area, the acid rain frequency was 48.44% , and the acid rain occurred mainly in the period of January to April. The order of acid rain frequency in various functional areas was factory region > urban area > county suburb > town suburb > nature reserve > county rural area. All of the trace metals in wet deposition during the sampling period were lower than the National Environmental Quality Standard for Surface Water Standard of Class III. Cd, Cu, Ph and Zn were found exceeding the standard of class I , and the pollution in factory region was more serious compared to other functional areas. The extract pH of dry deposition in urban area was in the range of 4.91-6.74, with an average value of 5.79. The order of dry deposition in various functional areas was factory region > county suburb > urban area > county rural area > town suburb > nature reserve, which was exactly the same as that of the wet deposition, indicating the similar sources of dry and wet deposition. In urban area, the contents of Ba, Co, Cu, Cr, Li, Mn, Ni, Sr, Zn in dry deposition were greater than those in wet deposition, but the contents of Al, As, B, Bi, Cd, Fe, Ph, Sb, Sn, Ti, V showed the opposite trend. Analysis of the enrichment factors showed that Al was in moderate enrichment, while Bi and Cd were significantly enriched.

[Seasonal Variation and Source Analysis of the Water-soluble Inorganic Ions in Fine Particulate Matter in Suzhou].

A total of 87 daily PM2.5 samples were collected in the urban area of Suzhou city during 2015, representing spring, summer, autumn, winter, respectively. Mass concentration of PM2.5 was analyzed gravimetrically. Water-soluble inorganic ions, including F-, Cl-, NO3-, SO42-, Na+, NH4+, K+, Mg2+and Ca2+, were determined by ion chromatography. The average mass concentration of PM2.5 was (74.26±38.01) µg·m-3. The seasonal variations of PM2.5 concentrations decreased in the order of winter > spring > autumn > summer. The average total mass concentrations of 9 ions was (43.95±23.60) µg·m-3, and the order of concentration of ions was NO3- > SO42- > NH4+ > Na+ > Cl- > K+ > Ca2+ > F- > Mg2+. Seasonal variation of ion concentrations was significant, with the highest concentration observed in winter and the lowest in summer. The secondary inorganic species, including SO42-, NO3- and NH4+ (SNA) were the major components of the water-soluble ions in PM2.5. SNA's correlations with each other were significant. SO42-, NO3- and NH4+ were probably in the form of NH4NO3 and (NH4)2SO4. The [NO3-]/[SO42-] ratio approaching to 1 implied that mobile sources were as important as stationary sources. Ion balance calculations indicated strong correlations between anion and cation equivalents. The PM2.5 was acidic. Industrial emission, combustion process, secondary formation and fugitive dust were the major sources of the water-soluble ions in PM2.5..

Source of atmospheric heavy metals in winter in Foshan, China.

Foshan is a ceramics manufacturing center in the world and the most polluted city in the Pearl River Delta (PRD) in southern China measured by the levels of atmospheric heavy metals. PM2.5 samples were collected in Foshan in winter 2008. Among the 22 elements and ions analyzed, 7 heavy metals (Zn, V, Mn, Cu, As, Cd and Pb) were studied in depth for their levels, spatiotemporal variations and sources. The ambient concentrations of the heavy metals were much higher than the reported average concentrations in China. The levels of Pb (675.7 ± 378.5 ng/m(3)), As (76.6 ± 49.1 ng/m(3)) and Cd (42.6 ± 45.2 ng/m(3)) exceeded the reference values of NAAQS (GB3095-2012) and the health guidelines of the World Health Organization. Generally, the levels of atmospheric heavy metals showed spatial distribution as: downtown site (CC, Chancheng District)>urban sites (NH and SD, Nanhai and Shunde Districts)>rural site (SS, Shanshui District). Two sources of heavy metals, the ceramic and aluminum industries, were identified during the sampling period. The large number of ceramic manufactures was responsible for the high levels of atmospheric Zn, Pb and As in Chancheng District. Transport from an aluminum industry park under light north-west winds contributed high levels of Cd to the SS site (Shanshui District). The average concentration of Cd under north-west wind was 220 ng/m(3), 20.5 times higher than those under other wind directions. The high daily maximum enrichment factors (EFs) of Cd, Pb, Zn, As and Cu at all four sites indicated extremely high contamination by local emissions. Back trajectory analysis showed that the heavy metals were also closely associated with the pathway of air mass. A positive matrix factorization (PMF) method was applied to determine the source apportionment of these heavy metals. Five factors (industry including the ceramic industry and coal combustion, vehicle emissions, dust, transportation and sea salt) were identified and industry was the most important source of atmospheric heavy metals. The present paper suggests a control policy on the four heavy metals Cd, Pb, Zn, and Cu, and suggests the inclusion of As in the ceramic industry emission standard in the future.

[Determination of metal elements in PM2. 5 by ICP-OES with microwave digestion].

In the present work, a method was developed for determining lead, zinc, copper, cadmium, znd chromium in PM2. 5 by inductively coupled plasma-optical emission spectrometry (ICP-OES) analysis with microwave digestion and glass fibre filter collection of samples. The microwave digestion systems were investigated and the experimental conditions were optimized. The results show that (1) HNO3-H2O02 digestion system is more stable and complete than HNO3-HCl and HNO3-H2 SO4 digestion systems; (2) The most sensitive emission wave length of lead, zinc, copper, cadmium, and chromium are 220.353, 213.857, 327.393, 228.802, and 267.716 nm, respectively; (3) The highest signal-to-noise ratios were observed under the conditions: RF power of 1 300 W, peristaltic pump flow rate of 1.5 mL x min(-1), cooling gas flow rate of 15 L x min(-1), and carrier gas flow rate of 0.8 L x min(-1). In addition, the detection limit for these elements ranged between 2.02 x 10(-3) and 8.20 x 10(-3(µg x mL(-1), the relative standard deviations (RSD, n = 6) for the samples were in the range of 1.86%-2.82%, and the recovery for the elements determined was from 91.6% to 103.7%. The proposed method was used for determination of the above five elements in atmospheric fine particulate matter at Wanzhou Monitoring Site of Chongqing Institute of Green and Intelligent Technology. The results revealed that the atmospheric fine particulate matter at this monitoring site was not polluted by cadmium and chromium, lead was at the level of potential contamination, while zinc and copper were at the level of slight pollution.

[Pollution characteristics of organic acids in atmospheric particles during haze periods in autumn in Guangzhou].

Total suspended particles (TSP), collected during a typical haze period in Guangzhou, were analyzed for the fatty acids (C12-C30) and low molecular weight dicarboxylic acids (C3-C9) using gas chromatography/mass spectrometry (GC/MS). The results showed that the concentration of total fatty and carboxylic acids was pretty high during the haze episode. The ratios of fatty acids and carboxylic acids in haze to those in normal days were 1.9 and 2.5, respectively. During the episode of the increasing pollution, the fatty acids and carboxylic acids at night (653 ng x m(-3)) was higher than that (487 ng x m(-3)) in days. After that, the level of fatty acids and carboxylic acids in days (412 ng x m(-3)) was higher than that (336 ng x m(-3)) at night. In general, the time-series of fatty acids and carboxylic acids was similar to that of the air particle and carbonaceous species, however, the trend of the ratio of fatty acids and carboxylic acids to organic carbon was opposite to that of air particle and carbonaceous species. This ratio decreased with the increase of the concentration of air particle and after the night of 27th, the ratio increased with the decrease in the concentration of air particle. The results showed that haze pollution had a significant inhibitory effect on the enrichment of fatty and carboxylic acids. Based on the ratio of malonate to succinate (C3/C4), it could be found that primary sources contribute more to the atmospheric fatty and carboxylic acids during the autumn haze pollution periods in Guangzhou.

Increased levels of lead in the blood and frequencies of lymphocytic micronucleated binucleated cells among workers from an electronic-waste recycling site.

In recent years, adverse health effects of chemicals from electronic waste (e-waste) have been reported. However, little is known about the genotoxic effects of chemicals in e-waste. In the present study, air concentrations of the toxic metals at e-waste and control sites were analyzed using inductively-coupled plasma mass spectrometry. Levels of toxic metals (lead, copper and cadmium) in blood and urine were detected using atomic absorption spectrophotometry in 48 exposed individuals and 56 age- and sex-matched controls. The frequencies of lymphocytic micronucleated binucleated cells (MNBNCs) were determined using a cytokinesis-block micronucleus assay. Results indicated that blood lead levels were significantly higher in the exposed group (median: 11.449 µg/dL, 1st/3rd quartiles: 9.351-14.410 µg/dL) than in the control group (median: 9.104 µg/dL, 1st/3rd quartiles: 7.275-11.389 µg/dL). The exposed group had higher MNBNCs frequencies (median: 4.0 per thousand, 1st/3rd quartiles: 2.0-7.0 per thousand) compared with the controls (median: 1.0 per thousand, 1st/3rd quartiles: 0.0-2.0 per thousand). Additionally, MNBNCs frequencies and blood lead levels were positively correlated (r = 0.254, p<0.01). Further analysis suggested that a history of working with e-waste was a predictor for increased blood lead levels and MNBNCs frequencies in the subjects. The results suggest that both the living and occupational environments at the e-waste site may be risk factors for increased MNBNCs frequencies among those who are exposed.

[Characteristics of volatile organic compounds during haze episode in Foshan city].

Volatile Organic Compounds (VOCs) in Foshan City were investigated in December 6 to 30 2008. The concentrations of VOCs in haze days were significantly higher than those in no-haze days. Toluene (68.93 microg x m(-3) +/- 37.78 microg x m(-3)) was the most abundant compound of VOCs in haze days and i-pentane (20.59 microg x m(-3) +/- 14.28 microg x m(-3)) was the most abundant compound in no-haze days, respectively. During haze episodes, the diurnal variations of alkanes and alkynes were not significantly; however, alkenes and aromatic hydrocarbon decreased significantly at noon. During no-haze episodes, the diurnal variations patterns of VOCs were stable. Propylene-equivalent concentrations in haze days were significantly higher than those in no-haze days, toluene was the most abundant compound of Propylene-equivalent concentration in haze days, followed by propene and ethene; propene was the most abundant compound in no-haze days, followed by ethene and 1-butene. High concentration of benzene (18.1 microg x m(-3)) in haze days posed a great health threat to public in Foshan city. Both diurnal variation of VOCs and measured ratios indicated vehicular emissions acted as the main sources of most VOCs and other sources like solvent application also contributed to VOCs (benzene and toluene).

[Influence of fog processes on characteristics of individual particles in the urban atmosphere of Beijing].

The purpose of this study is to investigate the effect of fog processes on the physical and chemical properties of aerosol particles in an urban atmosphere. Atmospheric particles were collected in the urban atmosphere of Beijing during fog and non-fog episodes. The morphology, size and elemental composition of individual particles were characterized using a scanning electron microscope (SEM) equipped with an energy dispersive X-ray spectrometer (EDX). EDX analysis showed that elongated particles were composed of Ca-K-S or Ca-S, and most sub-round particles contained sulfur. Large amounts of elongated and sub-round particles were identified in the samples collected during fog episodes, and they were rarely detected in the samples collected during non-fog episodes. This suggests that the high relative humidity in the fogs facilitated the formation of elongated and sub-round particles. Number concentrations of particles larger than 0.2 microm were about 5 to 8 times higher during the fog episodes. In addition, a new mode around 0.4 microm appeared in number size distribution of particles during the fog episodes. These results indicate that heterogeneous reactions in the fogs could greatly change the chemical and physical properties of particles.

Diurnal variation of number concentration and size distribution of ultrafine particles in the urban atmosphere of Beijing in winter.

Number concentration and distribution of airborne particles in the size range 5.6 to 560 nm diameter were measured in Beijing for a 15-d period in winter 2005. Daily average number concentrations of nucleation mode (5.6-20 nm), Aitken mode (20-100 nm), and accumulation mode (100-560 nm) particles, and total particles were 17500, 32000, 4000, and 53500 cm(-3), respectively. Average particle size distribution was monomodal with a mode diameter of about 40 nm at night and bimodal with mode diameters of about 10 and about 40 nm during the daytime. New particle formation events, which were connected to diurnal variation of nucleation mode particles, were observed in more than half of the observation days. The events often started around 10:00-11:00 Chinese Standard Time (CST) and ended up after 3-4 h. Concentrations of Aitken and accumulation mode particles increased from midnight and reached their maxima at about 10:00 CST, and then decreased and became the lowest in the afternoon. Analysis of diurnal cycles in traffic volume and meteorological parameters revealed that the accumulation of the particles in Aitken and accumulation modes in the morning was influenced by formation of an inversion and increase in vehicle emission, and dispersion of such particles in the afternoon was associated with more effective vertical mixing and higher wind speed.

[Characteristics of mineral component in ambient PM2.5 in Beijing].

To understand the concentration levels and temporal variations of the mineral component of PM2.5 in the ambient air of Beijing, weeklong samples were simultaneously collected for one year at Qinghuayuan and Chegongzhuang. The concentrations of five major crustal elements Al, Si, Ca, Mg, and Fe exhibited similar significant weekly variations, with their maximum values in the week of a serious dust event in the spring of 2000. Obvious seasonal pattern was also found for these elements, indicating different influences on fine mineral particles from the source emissions and meteorology in different seasons. Soil dust concentration increased from a low level in summer to the peak value (21.1 microg x m(-3)) in spring, suggesting that frequent dust events made a significant contribution to fine soil dust. A large number of construction activities in Beijing substantially increased the loading of fine calcium-bearing particles, and their emissions thus need to be further controlled.

Application of ion chromatography to the determination of water-soluble inorganic and organic ions in atmospheric aerosols.

A simple, sensitive and convenient ion chromatography(IC) method was established for the simultaneous determination of twelve water-soluble inorganic anions(F- , Cl- , NO2(-), NO3(-), SO3(2-), SO4(2-) , PO4(3-)), and fifteen water-soluble organic ions(formate, acetate, MSA, oxalate, malonate, succinate, phthalates, etc.) in atmospheric aerosols. The linear concentrations ranged from 0.005 microg/m3 to 500 microg/m3 ( r = 0.999-0.9999). The relative standard deviation (RSD) were 0.43%-2.00% and the detection limits were from 2.7 ng/m3 to 88 ng/m3. The proposed method was successfully applied to the simultaneous determination of those inorganic ions and organic ions in PM2.5 of Beijing.