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Carbon trading is an important market instrument and policy tool to promote China's practice of low-carbon energy conservation and strive to achieve carbon peaking by 2030 and carbon neutrality by 2060. To improve market flow and respond to the national strategy to support the development of carbon trading in China, a smart carbon trading process optimization framework based on blockchain technology is developed in this article. First, the paper analyzes the current state of carbon trading in China's power sector and identifies the future development trend and barriers to carbon trading in China. Second, a framework for a smart carbon trading system based on the structure and traits of blockchain technology is created to optimize the carbon trading process. Third, the smart contract for the smart carbon trading system is built (including execution logic, transaction matching, contract fulfillment, and other elements). This mechanism measures the reputation of trading users. Finally, policy suggestions are provided to solve the current issues and challenges. According to the research conducted for this paper on "blockchain + carbon trading in China," carbon trading supported by blockchain technology can guarantee transaction security and efficiency, accurately preserve transaction records, and offer a high level of automated settlement. [ABSTRACT FROM AUTHOR]

Among CCUS methods, carbon dioxide-enhanced coalbed methane (CO2-ECBM) is one of the most important applications. The CO 2 migration range in the reservoir and impact on the fractures are the keys to safe storage. Multiple geophysical methods of time-lapse DAS-VSP, passive microseismic, and InSAR have been taken to monitor the CO 2 -ECBM project in Shizhuang Town, Shanxi Province, China. The time-lapse DAS-VSP technology captures the changes of seismic amplitude due to CO 2 injection. Three phases of passive microseismic monitoring detected 217 microseismic events and 48 earthquakes. Based on the distribution of the microseismic events, the CO 2 migration direction was inferred to be northeast of the injection well. A quantitative calculation method for the impact of natural earthquakes on the storage site was proposed. Studies on the relationship between microseismicity and earthquakes suggest that natural earthquakes do not significantly affect CO 2 storage in the study area. InSAR combined unmanned aerial vehicle (UAV) photography measurement technology obtained the surface deformation results with a maximum displacement of 21 mm. The surface deformation also shows CO 2 migration in a northeast direction, consistent with microseismic results. Finally, in order to verify the monitoring results of the above methods, the gas detection in the production well around the injection site was analyzed. The analysis results show that the primary direction of CO 2 migration in the study area is the northeast direction, followed by the east direction. These geophysical techniques validate the accuracy of the monitoring results and provide new technical support for future CCUS projects. [ABSTRACT FROM AUTHOR]

Accurate assessments of spatial–temporal variations in water use efficiency (WUE) are important for evaluation of carbon and water balances. In this study, the spatial and temporal patterns of WUE and associated climate controls in China's Loess Plateau are investigated over 2000–2010 by utilizing remote sensing data and multiple statistical methods; which provides a greater understanding about how WUE changed after the Grain to Green Program (GTGP) launched. Carbon sequestration (i.e., net primary productivity, NPP) is estimated with the CASA model and water consumption (i.e., evapotranspiration, ET) is obtained from the MODIS product (i.e., MOD16). Our results identify an increasing trend in the regional mean NPP that amounted to 7.593 g C/m 2 ·yr with an average value of 310.035 g C/m 2 ·yr. Changes in ET are segmented into three stages, the growth (2000 − 2003), decline (2004–2006) and stable (2007–2010) stages. Regional WUE is measured at 0.915 g C/mm·m 2 and shows an upward trend at a rate of 0.027 g C/mm·m 2 ·yr. Spatially, significant regional heterogeneity is found in both NPP and WUE with gradients decreasing from the southeast to the northwest, but sharp rises detected in northern Shaanxi. At the biome level, the annual average WUE of the four groups decrease in the order of grasslands > woodlands > shrublands > croplands. Moreover, all biomes in the grassland ecosystems exhibit a growth in WUE as does the arid desert zone in the northwestern region, suggesting that vegetation in moderately water-deficient areas may have a higher tolerance to drought. Among different meteorological factors, precipitation and drought severity index (DSI) in the Loess Plateau show a latitudinal zonality and influences the WUE, which indicated that the moisture rather than temperature would be the major control factor of the regional WUE. Finally, significant variation in vegetation WUE sensitivity in response to meteorological factors is noted. Temperature is found to be the dominant driving factor of shrublands WUE, whereas precipitation primarily influenced the WUE of grasslands, croplands, and woodlands. [ABSTRACT FROM AUTHOR]

Residential coal combustion is a prominent source of brown carbon (BrC) aerosols, but knowledge of their molecular structures and optical absorption were limited, which have notable used in ambient BrC source identification and radiative forcing calculation. In this study, the Fourier transform–ion cyclotron resonance mass spectrometry combined with partial least squares regression analysis as well as Fourier transform infrared spectroscopy analysis were used to insight the molecular compounds and structures of BrC from anthracite and bituminous coal combustions between traditional and improved stoves. The absorption Ångström exponents (AAE) and mass absorption efficiency (MAE) values for the BrC emitted from the combinations of bituminous were both 1.2–2.5 times lower than those of anthracite, interpreting that the BrC from the anthracite emissions had greater light-absorbing capacity. In contrast, the emission factor of light absorption (EF Abs) at 365 nm for the bituminous coal combusted in the traditional stove was the highest among all the tested scenarios, which revealed that the incomplete combustion of bituminous coal could emit more BrC. It was noted that primary BrC emitted from the coal combustion with traditional stoves contains higher aromaticity groups of C–C and C＝O and higher S containing organics, whereas more aliphatic groups were found in BrC using the improved stoves. N-containing (CHON and CHONS) compounds were dominated in the total molecular formula of BrC, whereas the sum of CHON and CHO groups had high double-bond equivalent (DBE) values contributed 53.5%–87.1% to the total BrC absorption. Moreover, for CHOS, the lowest of estimated molecular absorption, DBE, and DBE/C should attribute to the non-chromophoric or weak absorptive S-containing compounds. This study supplied an effective evaluation method to compare BrC emissions and their absorption for coal combustion on regional scale. [Display omitted] • The BrC emitted from anthracite coal presented high light-absorbing capacity. • Calculated CHON and CHO compounds showed dominated light absorptions in BrC. • S-containing compounds present the less absorption of BrC. [ABSTRACT FROM AUTHOR]

Abstract: Lessons learnt from accidents are essential sources for updating state-of-the-art requirements in pollution accident prevention. To improve this input in the People''s Republic of China in a systematic way, a database for collecting and evaluating major pollution accidents is being established. This is being done in co-operation with Chinese Society for Environment Sciences and other national Institutions. At the time of writing over 80 major events from 2002–2006 have been collected. In this paper, a summary evaluation on the major polluting events in China from 2002 to 2006 is presented and some basic lessons drawn shown. There is no a systematic pollution accident notification system currently in China. The results from root cause analysis underline the importance of emergency measures, maintenance, human factor issues and the role of safety organization. Chronic pollution, especially water pollution and air pollution should be paid the same attention as the sudden pollution. It is important to keep in mind that collecting information from major accidents represents a small percentage of the actual number of events taking place. [Copyright &y& Elsevier]

Humic-like substances (HULIS) in particulate matter (PM) play critical roles in the atmospheric changes in our environment. In this study, high time resolution PM 2.5 samples were collected to insight the abundances, spectroscopic characters, chemical groups, and oxidative potential of HULIS in Xi'an, China. The average mass concentrations of HULIS in term of carbon (HULIS-C) was 11.55 ± 5.85 and 8.28 ± 2.23 μg C m−3 in winter and summer, respectively. The diurnal variations of HULIS displayed three peaks (03:00–07:00, 10:00–14:00, and 18:00–21:00 LT) in winter, but a single peak (08:00–12:00 LT) in summer. The optical parameters show obvious difference between winter and summer. Fourier Transform infrared (FT-IR) spectra revealed that the HULIS mainly consisted of aliphatic chains, aromatic rings, and carboxylic groups. The FT-IR spectra proved that the aromatic compounds and carboxylic acids dominated the diurnal variation in winter, while carboxylic acids were responsible for that in summer. The normalized oxidative potential of HULIS exhibited an inverse trend with the HULIS-C concentration measured by the DCFH assay. The diurnal reactive oxygen species (ROS) productions from HULIS presents three valleys (03:00–07:00, 10:00–14:00, and 18:00–21:00 LT) in winter but only a single valley (08:00–12:00 LT) in summer. In addition, a positive correlation (R2 ≈ 0.6, p ＜0.01) between the oxidative potential and specific ultraviolet absorbance at a wavelength of 254 nm (SUVA 254) in winter suggested that the oxidative power of HULIS could be more related to the compounds with high light absorbance, high aromaticity, and molecular weight. The results of this study offer more solid knowledge on the spectral and chemical characteristics and oxidative potential of the HULIS in PM 2.5 of the typical city in northwest China. [Display omitted] • Oxidative potential of HULIS decreased with the increase of HULIS-C concentration. • Aromatic compounds and carboxylic acids dominated the diurnal variation in winter. • Carboxylic acids were responsible for the diurnal variation in summer. • The oxidative power of winter HULIS was related to high light-absorbance and high-aromaticity compounds. [ABSTRACT FROM AUTHOR]

The willingness of migrating due to air pollution is widespread in China. However, there is a lack of direct evidence and discussion regarding whether this willingness has been translated into action. In this study, PM2.5 concentrations were used to represent air pollution in each city and were compared with individual migration data from the China Labor-force Dynamics Survey (CLDS) to examine population migration effects caused by air pollution. This study showed that (1) Population migration between Chinese cities shows sensitivity to air pollution, and air pollution increases the probability of moving away for local population. This finding is held under multiple robustness and endogeneity tests. (2) Population migration effects caused by air pollution were more pronounced among women, middle-aged people, those with lower educational levels, from agricultural households, Han Chinese groups, and populations in southern cities. (3) The use of individual self-rated health data verified that physical health is an important channel through which individual migration decisions are influenced by air pollution, the older an individual, the more his or her health was affected. In light of these findings, this study led to conclusions regarding targeted policy recommendations in terms of talent clustering, social equity, and demographic balance. [ABSTRACT FROM AUTHOR]

Abstract: An ethnicity- and gender-specific normal reference database is necessary for the clinical dual-energy X-ray absorptiometry (DXA) assessment of skeletal status in Chinese children. We used a Lunar Prodigy DXA densitometer to measure bone mineral density (BMD), bone mineral content (BMC), and bone area (BA) at total body and subcranial skeleton for 877 healthy Chinese children (505 boys, 372 girls) aged 5–13yr. The height-for-age, BA-for-height, and BMC-for-BA percentile curves were developed using the LMS method (L, power in Box-Cox transformation; M, median; S, coefficient of variation). We found that total body BMD and subcranial skeleton BMD were highly correlated (r =0.701–0.949), and that total body BMD was significantly higher than subcranial skeleton BMD for each gender and age group (p <0.001). No gender differences in total body and subcranial skeleton BMD were found. Total body lean mass correlated highly with total body BMC and subcranial skeleton BMD and BMC (boys: r =0.888–0.953, girls: r =0.917–0.967) and moderately with total body BMD (boys: r =0.684, girls: r =0.777). The head region accounted for 16–52% and 16–49% of the total body BMC in boys and girls, respectively, and the percentages were negatively correlated with age (boys: r =−0.824, girls: r =−0.864) and height (boys: r =−0.911, girls: r =−0.922). Regression analyses showed that age explained more variance in subcranial skeleton BMD (boys: R 2 =0.641, girls: R 2 =0.685) than in total body BMD (boys: R 2 =0.387, girls: R 2 =0.472). In summary, we have presented an ethnicity- and gender-specific densitometric normal reference database for Chinese children aged 5–13yr. It should allow for an appropriate clinical assessment of total body bone density in Chinese children as measured by the Lunar Prodigy DXA densitometer. [Copyright &y& Elsevier]

Abstract: This study was aimed at assessing the correlations between the bone mineral density (BMD) of the hand and other skeletal sites in Chinese women and men. We measured the BMD of the total body, the anteroposterior lumbar spine (L2–L4), bilateral proximal femurs (i.e., total hip, femoral neck, and trochanter), and bilateral total hands in 363 Chinese adults (96 males, 267 females) using dual-energy X-ray absorptiometry (DXA). Data were analyzed by descriptive statistics, Student''s t tests, and Pearson''s correlation coefficients (r). We found that bilateral hand measurements reduced precision error by 36% as compared with a single hand measurement. Dominant hand BMD was significantly higher than nondominant hand BMD. For both the dominant and nondominant sides, hand BMD was significantly higher in males than in females. Hand BMD correlated significantly (p <0.001) with the BMD of all skeletal sites for all subjects (r =0.681–0.848), the male group (r =0.568–0.857), and the female group (r =0.687–0.859). After normal references for the Chinese population have been established, further investigations may determine the clinical usefulness of hand BMD measurement in the diagnosis of osteoporosis and the prediction of fracture risk. [Copyright &y& Elsevier]

China's traditional automobile industry lags behind that of the developed countries, but the development of New Energy Vehicles (NEVs) is an opportunity to catch up with the global automobile industry. In China, there has been a widespread attempt to "overtake on the curve" by developing cleaner technology for NEVs. To help with this transition, the Chinese government has introduced a large number of policies to promote the development of the NEV industry. In this study, we examined whether these policies have been effective by analyzing data about policies for China's NEV industry from 2006 to 2018, as well as the NEV patents filed in the United States, Japan, Germany, France, Korea, and China from 1988 to 2018. This paper uses quantitative analysis of policies and factor analysis. The results of the policy quantification regression analysis show that China's industrial policy has a significant influence on the number of patents. For example, China's aim to promote technological progress has been effective in developing an indigenous NEV industry, but whether China will succeed in "overtaking on the curve" is still unclear. The current state of development of NEV patents does not show China have a leading edge in NEV technology. China's NEV industry policies should be further strengthened, especially the core policies on technological innovation. • China's policy of encouraging new energy vehicles is effective. • China's "overtaking on the curve" strategy has not yet meet the expectations. • This study provides a reference for the policy making of the new energy automobile industry. [ABSTRACT FROM AUTHOR]

Agricultural drought seriously threatens the food and ecological security of most of the world's developing countries. Data-driven integrated agricultural drought index with remote sensing provides an effective tool to monitor, evaluate, and predict the agricultural drought. However, there is still a lack of comprehensive analytical work on taking the most effective machine learning (ML) and deep learning (DL) methods to construct such integrated drought index. In other words, it is still unclear whether the recent DL methods can improve integrated drought monitoring as compared with the currently widely used ML methods. Therefore, we critically evaluated the performances of four representative DL methods (represents the four currently popular DL network types) i.e., Entity Embedding Deep Neural Network (EEDNN), One-dimensional Convolutional Neural Network (1D-CNN), Gated Recurrent Unit (GRU), and Self-Attention Mechanism (SAM) and three widely used tree-based ML methods i.e., Cubist, Random Forest (RF), and Light Gradient Boosting Machine (LGBM), through constructing a QuickDRI like integrated drought index (abbreviated as QuickDRI-China). About 30 years of meteorological data, 14 years of remote sensing data, and various biophysical variables in China such as land use/land cover, available water capacity, irrigated agriculture, elevation, and ecoregion were employed in this study. Results showed that the EEDNN performed best, followed by the RF and LGBM, and then the other methods including the currently wide used Cubist, according to the station accuracy evaluations, spatial description evaluations, and responses to specific drought event. The tree-based ML methods such as RF and LGBM are still competitive in constructing the integrated agricultural drought index at the current stage. However, the higher accuracy, the smoother spatial description, and the more responsive ability of the EEDNN demonstrate great potential of DL methods. The future integrated agricultural drought monitoring with remote sensing should develop a specialized DL network for heterogeneous agricultural drought features. • Various deep learning approaches were examined for integrated drought monitoring. • Tree-based ensemble learning methods were effective. • Deep learning has unique advantages for assessing spatial description of agricultural drought. • Deep learning has great potential to improve integrated drought monitoring. [ABSTRACT FROM AUTHOR]

[Display omitted] • Yudongzi BIFs were formed at ca. 2.8 Ga, and suffered two-stage metamorphism. • Yudongzi BIFs were formed on the back–arc basin setting. • Yudongzi complex combined to Yangtze Block later than Paleoproterozoic. The Yudongzi banded iron formations (BIFs) are widely spread in the Neoarchean Yudongzi Group of the Bikou Terrane, Central China. Their sedimentary and metamorphic ages, however, remain controversial, either their forming or reworking processes. In this contribution, we conducted an integrated study of zircon U-Pb-Hf isotope geochemistry, as well as mineral and bulk-rock geochemistry on the Heishan'gou iron deposit, the largest iron deposit of the Yudongzi BIFs, to constrain their formation and metamorphism ages, source of ore-forming material and tectonic setting. Mineral chemistry analysis indicates that the amphibolite, host-rock of the Heishan'gou deposit suffered amphibolite facies metamorphism. LA-ICP-MS U-Pb dating of zircon grains from orthometamorphic host-rocks suggests that the Heishan'gou deposit was formed at the early Neoarchean (2781 ± 43 Ma for amphibolite and 2776 ± 43 Ma for plagioclase-hornblende schist), and metamorphosed at ca. 2480 ± 26 Ma and 1818 ± 44 Ma, respectively. The low contents of aluminum, titanium and high field strength elements in BIFs suggest that they are detritus-free marine chemical precipitates. The rare earth elements (REE) and Y patterns of BIFs display seawater-like signatures with light REE depletion, and positive La and Y anomalies. Meanwhile, their positive Eu anomalies suggest that submarine hydrothermal fluid might also be involved in the precipitation of BIFs. Combined with zircon Hf isotope data and geochemical compositions of amphibolites, it is proposed that the Yudongzi BIFs should be formed at back-arc basin setting. Compared with the representative Archean continent nucleus of the Yangtze Block (Kongling Complex), the Yudongzi Complex experienced distinct crustal evolutionary history. It indicates that the Yudongzi Complex might represent the accretionary block combined to the Yangtze continental nucleus later than the Paleoproterozoic. [ABSTRACT FROM AUTHOR]

Abstract: The concentrations and depositional fluxes of polycyclic aromatic hydrocarbons (PAHs) were investigated in a dated sediment core collected from a tidal flat in Haizhou Bay, China. The USEPA''s 16 priority PAH concentrations ranged from 72.51ngg−1 dw in 1969 to 805.21ngg−1 dw in 2010, while the deposition fluxes were in the range of 102.36–861.02ngcm−2 yr−1. The PAH concentrations and fluxes changed dramatically with depth, suggesting changes in energy usage and corresponding closely with the historical economic development of eastern China. The levels of PAHs slightly increased from the late 1970s, following China''s “Reform and Open” policy of 1978; however, a drastic increase in the concentration of PAHs observed in 1990 was indicative of the rapid growth in coal and petroleum incomplete combustion byproducts, which was associated with the increase in economic development in this area. Furthermore, isomer ratio analysis and principle component analysis revealed the main anthropogenic pyrolytic source that causes PAH contamination in the coastal sediment. [Copyright &y& Elsevier]

In recent years, ultraviolet (UV) irradiation coupled with chlor(am)ination process is ubiquitous in secondary water supply systems in many cities of China. However, the disinfection by-products (DBPs) formation in a UV-activated mixed chlorine/chloramine system (MCCS) still remains unclear. In this study, the DBPs formation in a UV-activated MCCS was systematically investigated, considering influencing factors including the mass ratios of free chlorine to NH 2 Cl, UV irradiation, pH values, NOM types, Br− concentration and toxicity of the DBPs. Results indicated that DBPs formation decreased remarkably as mass ratio of free chlorine to NH 2 Cl changed from 5:0 to 0:5. The DBPs formation in humic acid (HA)-containing water was the highest, followed by those in fulvic acid (FA) and algal organic matter (AOM). Besides, better control of the DBP-related calculated toxicity can be achieved in acidic conditions regardless of the UV irradiation. Furthermore, in the presence of Br−, a significant reduction of DBPs formation could be achieved in a UV-activated MCCS. The findings also demonstrated that DBPs formation in real water can be effectively reduced at high UV fluence in a MCCS. ga1 • Mass ratio of HOCl/NH 2 Cl and UV irradiation significantly affected DBPs formation. • UV-activated MCC process reduced DBPs formation in alkaline conditions. • UV irradiation could control DBPs formation in Br−-containing water during MCC process. • MCC process achieved DBPs control in real water at high UV fluence. [ABSTRACT FROM AUTHOR]

There is growing evidence suggesting the enhancement of brown carbon (BrC) in severe haze episodes. In this study, hourly measurements of BrC in PM 2.5 were conducted in Xi'an, a typical city in northwestern China during winter and summer. The absorption coefficient for methanol exacts at 365 nm (b abs365, methanol , which is typically used as a proxy of methanol-soluble BrC) in the winter sampling period was over 7 times than that in summer. The mass absorption cross-section for methanol extracts (MAC 365, methanol , normalized by b abs365, methanol to organic carbon, OC) in winter sampling period was nearly 1.5 times of that in the summer. During the winter haze days, the average b abs 365, methanol peaked at midnight and the lowest values in the morning, in contrast to high levels in afternoon and low levels at night in non haze days. Unlike the diurnal patterns in winter, summer b abs365, methanol diurnal variation presented high midday and low afternoon levels in haze days. However, in non haze days, the pattern showed high morning levels and night low levels. Haze and non haze variations of chemical species levels, b abs365, methanol , and MAC 365, methanol during winter and summer sampling time showed that the effects of atmospheric aging were complex and could either enhance or reduce light absorption of BrC. Source apportionment based on positive matrix factorization receptor model and multiple linear regressions showed that primary emission was an important contributor to BrC emissions during the winter sampling period, whereas secondary formation played an important role in summer. Daily variations of b abs365,methanol , MAC 365,methanol , OC, OC/EC during winter and summer. Image 1 • High time-resolved BrC observation during winter and summer was conducted. • Atmospheric aging can either enhance or reduce light absorption by BrC. • Primary emission and secondary formation were important contributors to BrC during winter and summer, respectively. [ABSTRACT FROM AUTHOR]

Newborn ear deformity can be performed through Earwell infant ear correction system as a non-surgical treatment to avoid plastic surgery. In the newborn period, the auricle is soft and the cartilage is plastic, the deformed auricle shape can be treated by mechanical action. From April 2016 to December 2018, we selected the patients who underwent Earwell non-invasive correction system in Eye & ENT Hospital of Fudan University for newborn ear deformities, and analyze the treatment age, treatment time, efficiency and complication of these patients. There were 105 patients with 141 ears underwent Earwell non-invasive correction system for newborn ear deformities. The average age for treatment is 2.16 ± 2.28 months (0.23–12.0 months). The average treatment time is 1.14 ± 0.57 months (0.33–4.0 months). The treatment outcomes show 109 ears get excellent results, 27 ears good results and 5 ears poor results. For complications, there were 6 patients had localized skin rash and 5 had skin lesion which were cured after 3–5 days. Nine patients had different degree of recurrence. The treatment age less than 6 weeks had a better results than treatment age old than 6 weeks (χ2 = 4.48, p < 0.05). Except 5 poor results patients, the treatment efficiency is 96.4% (136/141) in this study. The Earwell infant ear correction system is proven to be a simple, non-invasive, high-efficiency, low-cost treatment method, which is more effective than traditional plastic surgery, and treatment efficiency of different types ear deformities can reach more than 95% in China. It is important to ensure the early treatment during the first 6 weeks. [ABSTRACT FROM AUTHOR]

Domestic solid fuels combustion produces a mass of fine particulate matter (PM 2.5). PM 2.5 -bound organics, including polycyclic aromatic hydrocarbons (PAHs), oxygenated-PAHs (OPAHs), phthalate esters (PAEs) and hopanes, were quantified in indoor, outdoor and personal exposure samples collected in rural Guanzhong Basin, China. The average concentration of total quantified PAHs in personal exposure samples was 310 ± 443 ng m−3, 1.5 times of those of indoor (211 ± 120 ng m−3) and outdoor (189 ± 115 ng m−3). Similar observations were found for the OPAHs and PAEs, i.e., much higher concentrations were seen in personal exposure samples. Hopanes average personal exposure concentration (13 ± 9.7 ng m−3) was comparable to indoors (15 ± 9.7 ng m−3) and outdoors (13 ± 9.6 ng m−3). Among four common heating ways applied in Chinese dwelling, the highest exposure levels to PAHs, OPAHs and PAEs were found for indoor coal chunks stoves. Concentration under electric power was 1.2–4.5 folds lower than those with solid fuels in this study, proved to be the cleanest energy for the household heating. The exposures to PM 2.5 on cell viabilities were also investigated. The largest reduction of 70% on cell viabilities was seen for indoor coal chunks stove housewives, indicating that the emissions from coal combustion had the greatest cytotoxic effects. The results evidenced that the heating ways in rural area could greatly impact on the housewife health in northwestern China. Advanced heating technology and protection should be conducted to reduce the personal exposures to PM 2.5 from domestic solid fuel combustions. Image 1 • Domestic solid fuels emit toxic particulate-bound organics in rural northern China. • Personal exposures to PAHs, OPAHs, PAEs were ∼1.5 times of indoors and outdoors. • PM 2.5 from coal chuck stove had the maximum decline in cell viability. • Use of electricity reduced personal exposure levels to organics by 1.2–10 times. [ABSTRACT FROM AUTHOR]

[Display omitted] • Characteristics of four biorefinery methods were compared shoulder by shoulder. • Photo-fermentation biohydrogen production exhibited the greatest economy. • Biomethane presented a maximum yield of 196.0 mL and gross thermal of 6468.4 J/gDM. • Target product of biomethane had the highest CO 2 emissions of 196.01 mL/g DM. Biorefinery technology promotes the realization of the Paris Agreement, China's achievement of its carbon peak, and carbon neutralization. Photo-fermentation biohydrogen production, dark fermentation biohydrogen production, biomethane production, and bioethanol production are several promising biorefinery methods. In this study, corn stover was used as the raw material, and the gas, liquid, and kinetic characteristics of four biorefinery methods were investigated. The production yield, gross thermal energy, economy, and greenhouse gas emissions of the target product per gram of corn stover were studied. The maximum yields of photo-fermentation biohydrogen production, dark fermentation biohydrogen production, biomethane production, and bioethanol production were 68.4 mL/g dry matter (DM), 47.4 mL/g DM, 196.0 mL/g DM, and 2.7 g/L, respectively. The maximum gross thermal energy obtained from biomethane production was 7017.3 J/g DM. The maximum economy of 1.4 RMB/g DM was observed in photo-fermentation biohydrogen production. The highest greenhouse gas emission of the target product from biomethane production was 196.0 mL/g DM. The results provide a reference for the efficient utilization of biomass resources and a comprehensive evaluation of biorefinery technology. [ABSTRACT FROM AUTHOR]

Comprehensive treatment of municipal solid waste (MSW) is an important issue facing current research. On the basis of MSW composition analysis, this paper investigates the sorting methods of MSW and the utilization of waste in northeastern China by combining theory, experimentation and practice. According to the physical and chemical properties of waste, manual sorting must first be completed followed by magnetic separation, pneumatic separation and water concentration. A green brick can later be made by mixing the crushed construction waste, which is selected manually, with other waste that is selected by machine. Select organic compounds can also be used to make methane by fermentation at temperatures of 35±3 °C at a inoculation rate about 25% and a PH value of near 7.0; the resulting solid rate would need to be controlled within 9–21%. The methane could be used to generate electricity after removing sulfur and CO 2 and drying. An organic–inorganic fertilizer could be made by adding 20–30% of crushed plant stalks into the biogas fermenter and mixing it evenly with added N, P and K after dehydration, secondary fermentation and granulation drying. Both the electricity and exhaust heat could be utilized to improve the utilization of energy. When applied to a model city, the comprehensive treatment system proposed is shown to improve resource utilization by approximately about 40% compared with conventional methods; thus, the goals of waste reduction and recycling have been achieved. [ABSTRACT FROM AUTHOR]

The Chinese walnut ( Juglans hopeiensis Hu) is an endemic temperate tree species and narrowly distributed in China. However, there are still few specific molecular markers for understanding genetic diversity of this walnut. In this study, more than 44 million sequencing reads were generated using Illumina sequencing technology. De novo assembly yielded 93,822 unigenes with an average length of 731 bp. Based on sequence similarity search with known proteins, a total of 39,708 (42.3%) genes were identified. Searching against the Kyoto Encyclopedia of Genes and Genomes Pathway database (KEGG) indicated that 15,903 (17.0%) unigenes. To contribute to its conservation and management, twenty five microsatellite markers were identified in J. hopeiensis were screened for polymorphism across 27 Chinese walnut tree individuals from two locations. The number of alleles ranged from two to nine, observed heterozygosity ranged from 0.016 to 0.933 (mean 0.468), and expected heterozygosity from 0.022 to 0.823 (mean 0.462). The polymorphic information content (PIC) ranged from 0.012 to 0.831 (mean 0.437). The development of these new microsatellite markers will be useful for studying population genetic structure, evolutionary ecology, conservation, and genetic breeding of this endemic walnut tree or other Juglans species. [ABSTRACT FROM AUTHOR]

Ecosystem net primary production (NPP) represents vegetation biomass increment after accounting for autotrophic respiration and is recognized as an important component of the terrestrial carbon cycle. In this study, the spatial and temporal patterns of NPP and their climate controls in China’s ecosystems for the period of 1982–2010 were analyzed by using a remote sensing-based carbon model (i.e., the Carnegie–Ames–Stanford Approach, CASA) and multiple statistical methods. Validation against NPP observations from 335 forests sites showed good performance of CASA over the study region, with an overall coefficient of determination ( R 2 ) of 0.73 and root mean square error (RMSE) of 132.9 g C m −2 yr −1 . Spatially, we found that the spatial pattern of China’s NPP showed gradients decreasing from the southeast toward northwest, which could be mainly explained by the spatial variability in annual precipitation. Temporally, China’s NPP showed a significant increasing trend at both the national and biome levels during 1982–2010, with an annual increase of 0.011 Pg C or 0.42%. However, the increasing trends in NPP were not continuous throughout the 29-year period at the national scale. On the other hand, it showed three periods where the trends changed, which was likely being caused by a shift in climate conditions and extensive drought. Air temperature was found to be the dominant climatic factor that controlled the interannual variability in NPP throughout the country except for arid and semi-arid regions in the middle-north and northwest parts of China, where the interannual variations in NPP were mainly explained by changes in precipitation. Similar results were also obtained at the seasonal scale that changes in NPP were generally controlled by that in air temperature except for summertime, in which higher NPP were favored by higher summer precipitation, whereas summer temperature was negatively correlated with NPP. At the monthly scale, NPP responded to change in temperature more rapidly than that in precipitation. However, temperature appeared to control NPP only in humid and semi-humid regions. For monthly NPP–precipitation relationship, the strongest positive relations were observed when NPP lagged behind precipitation by 1–3 months. However, deviating from the common hypothesis that plant in drier areas should respond to water availability more rapidly than in other regions, our analysis revealed a relative large time lag between monthly NPP and precipitation in arid ecosystems (i.e., 3 months). This result suggests that there may be a more complex mechanism of local water redistribution that controls vegetation water use (e.g., use of water from previous year precipitation) in extremely arid ecosystems. [ABSTRACT FROM AUTHOR]

Objective Although congenital microtia has been reported in various studies, little is known about the etiology of isolated and sporadic cases. The aim was to analyze potential risk factors for isolated and sporadic microtia using case–control study in East China. Methods The study analyzed data from the hospital-based recruitment for deliveries between 2007 and 2013. Nine hundred eleven patients with microtia enrolled in the phenotypic characterization analysis, and then were adjusted by sex, age, region, syndrome and family history to compare with 562 random normal controls for potential risk factors. Results Microtia is observed more often in males (69.7%), and the cases were typically unilateral (74.0%), right-sided (57.2%), sporadic (92.0%) and isolated (69.5%). Mothers of children with microtia were more likely to have suffered a periconceptional cold-like syndrome as well as to have had a history of previous spontaneous abortion. Inflammatory infection (aOR, 3.56; 95% CI, 2.07–6.13) and chemical exposure (aOR, 2.77; 95% CI, 1.78–4.32) was associated with a higher risk of microtia. However, threatened abortion was not the risk factor (aOR, 1.14; 95% CI, 0.78–1.67), using progesterone may increase the risk (aOR, 1.92; 95% CI, 1.03–3.59). Conclusion The results of phenotypic characterization analysis were similar to other studies. By controlling the effects of potential confounders, some risk factors could be teratogens of isolated and sporadic microtia in East China. [ABSTRACT FROM AUTHOR]

Eutrophication in agricultural drainage ditches by over-fertilization with nitrogen and phosphorus is a serious environmental concern. Various management practices have been proposed to help to alleviate nutrient quantity transported to Tai lake. The current study was carried out to compare the nutrient mitigation capacity of a constructed ecological ditch (C) and a traditional soil ditch (T) of the similar size and landform in Taihu basin. Results show that there was a very slight difference existed in nitrate nitrogen (C: 7.7%; T: 6.2%) percent reductions between the two ditches, but significant differences existed for ammonium nitrogen (C: 31%; T: 7.6%), total nitrogen (C: 27%; T: 5%), and total phosphorus (C: 26%; T: 9.2%) after the ditches run under stable conditions. However, both of the agricultural drainage ditches were able to mitigate nutrients and reduce the quantity reaching to downstream aquatic receiving systems. In order to provide a higher and more stable pollutants degradation effect, further studies are needed to optimize the ditch structure design and examine ecosystem dynamics. [ABSTRACT FROM AUTHOR]

Abstract: High levels of organochlorine pesticides (OCPs) such as hexachlorocyclohexanes (HCHs) and dichlorodiphenyltrichloroethanes (DDTs) have been found in soil of the Pearl River Delta (PRD), attributable to high pesticide application in this area. Consequently, the occurrence and environmental effect of HCHs and DDTs in the PRD have attracted considerable attention. However, study focusing on the influence of potential factors such as soil property on the environmental fate of HCHs and DDTs in the PRD has been rare. The present study aimed to investigate the impact of soil physiochemical properties on the distribution patterns and fate of soil HCHs and DDTs on a large spatial scale. Levels of HCHs (sum of α-, β-, γ- and δ-HCH) and DDTs (sum of 1,1,1-trichloro-2,2-bis-(p-chlorophenyl)ethane (p,p′-DDT), 1,1-dichloro-2,2-bis-(p-chlorophenyl)ethane (p,p′-DDD), and 1,1-dichloro-2,2-bis-(p-chlorophenyl)ethylene (p,p′-DDE)) in 151 soil samples covering all areas of the PRD and physiochemical parameters related to soil properties including pH, total organic carbon (TOC), total Fe (TFe), DCB-Fe (DFe), amorphous-Fe (AFe), complexed-Fe (CFe), total Mn (TMn), DCB-Mn (DMn), amorphous-Mn (AMn), complexed-Mn (CMn) and cation exchange capacity (CEC) were determined. The residual levels of HCHs and DDTs in soils of the present study, which are mainly controlled by soil TOC and CFe content and varying spatially with land use types, may potentially pose ecological risk to plants and animals. On the other hand, transformation of soil HCHs may be affected by pH and DDT transformation correlated significantly with AFe and CFe. Currently, soil has become an important secondary source of OCPs and the re-emission potential of OCPs in soil was mainly affected by soil OCP concentrations and land use types. [Copyright &y& Elsevier]

The aim of this study was to examine the seasonal distribution in clinical onset of autoimmune encephalitis (AE) in a multi-center cohort in China. This retrospective study consecutively recruited patients with new-onset definite neuronal surface antibody-associated AE between January 2015 and December 2020 from 3 tertiary hospitals. Demographic and clinical characteristics of the participants were comprehensively collected. Statistical analyses were performed using R. Of the 184 patients of AE in our database, 149 (81.0%) were included in the final analysis. The median age of onset was 40.0 years, and 66 (44.3%) patients were female. AE predominantly started in autumn (47, 31.5%) and summer (43, 28.9%) months. Summer-autumn predominance of the clinical onsets was also present in the anti- N -methyl- d -aspartate receptor (NMDAR) encephalitis group (54, 60.0%) and anti-leucine-rich glioma inactivated 1 (LGI1) encephalitis group (20, 76.9%). No obvious seasonal variations were observed among gender, onset age, disease duration, prodromal symptoms, clinical type of initial symptoms, and disease severity by the time of admission. This study suggested summer-autumn predominance of the clinical onsets in patients with AE, especially anti-NMDAR and anti-LGI1 encephalitis. Therefore, clinicians should have a high index of suspicion for AE in encephalopathy patients in summer and autumn period. [Display omitted] • We aimed to clarify the seasonal distribution in clinical onset of AE in a multi-center cohort. • Seasonal predominance of the clinical onset in patients with AE was summer and autumn periods. • Summer and autumn predominance of clinical onset was present in anti-NMDAR and anti-LGI1 encephalitis. • No obvious seasonal variations were observed among demographic and clinical features. [ABSTRACT FROM AUTHOR]

Household solid fuel combustion for heating in winter is a substantial source of air pollution in rural areas of northwest China. The present study investigated the concentration characteristics and health risks of particulate matter (PM) and its organic compounds, including polycyclic aromatic hydrocarbons (PAHs), oxygenated PAHs (OPAHs), and phthalate esters (PAEs). Indoor air and housewives' personal exposure (PE) samples were collected in Guanzhong Basin, among rural households relying on various solid fuels for heating in winter. Indoor PM primarily comprised fine PM (PM 2.5 , 76%), and its organic compounds were identified in particular abundance in households that used coal as the only domestic fuel (Group C, 96% in PM 2.5). The mean concentration of PE to PM 2.5 was 307 ± 120 μg·m−3, which was 2.4-times higher than the indoor concentration (130 ± 103 μg·m−3) because of the housewives' short-term exposure to high-concentration pollution emitted by solid fuel combustion. Organic compounds exhibited the same pattern, with PE samples having a 44% higher concentration than indoor samples. The correlation of PM 2.5 -bound organics between indoor and PE samples in Group C (R2 = 0.9) was higher than that in the group using coal and biomass (Group M, R2 = 0.6), indicating the stronger correlation of single-fuel heating method. The PE/indoor ratio of high molecular weight (HMW) PAHs in Group C (2.5) was higher than that of the other organic compounds (1.3) because HMW PAHs emitted through coal combustion had a larger effect on PE. This further led to higher incremental lifetime cancer risks (ICLRs) via inhalation pathway among housewives in Group C (2.4- and 1.2-times higher risk for PAHs and PAEs, respectively) than among those in Group M. However, inhalational ILCR values of Group M were still 2.1–340-times higher than the international safety standard (10−6). Therefore, the upgradation of domestic fuels and heating ways is urgently needed in rural area of northwest China to reduce indoor air pollution and health risks. Unlabelled Image • ~78% TSP was observed to be PM 2.5 in rural households using solid fuels in winter. • PM 2.5 -bound PAHs, OPAHs and PAEs accounted for an average of 95% of those in TSP. • Personal exposure (PE)/indoor PM 2.5 ratios were 2.1 in Group M and 2.9 in Group C. • Elevated PAH concentrations in PE PM 2.5 were mainly observed in HMW PAHs in Group C. • The organics in Group C showed higher carcinogenicity and oxidability than Group M. [ABSTRACT FROM AUTHOR]

Subaqueous volcanic-hydrothermal field is a complex hybrid geological system, where sediments originated from volcanic, hydrothermal, lacustrine, terrestrial, and biotic sources are mixed. Recent petrological studies on such sediments have indicated a potential relationship between volcanic-hydrothermal activities and oil generation and accumulation. Here, we explore the mechanisms of sedimentation and oil accumulation in well-laminated organic-rich fine-grained sedimentary rocks in Permian Lucaogou Formation deposited in the lacustrine Santanghu rift basin, NW China. We conducted petrographic, carbon and oxygen isotopic, and organic geochemical analyses of fifty-four core samples from three wells (forty-eight samples from Well W1, two from W2, four from W3) designed for tight oil exploration. Four main observations and interpretations are: 1) The fine-grained sediments are a mixture of volcanic-hydrothermal detrital feldspar grains, authigenic quartz crystals, and primary lacustrine dolomite, forming interbedded tuffaceous shale and dolostone; 2) authigenic quartz crystals were precipitated from acidic hydrothermal fluids, whereas fine-grained angular alkaline feldspars were derived from subaqueous volcanic eruption; 3) the TOC content and oil generation potential increase with increased mixing of feldspars and carbonate minerals. Hence, the dolomite-bearing tuffaceous shale and tuffaceous dolostone are the best source rocks; and 4) the fine-grained sedimentary rocks are interpreted as a subaqueous volcanic-hydrothermal deposit that controls the source potential. The sedimentary processes of an ancient sediment-hosted geothermal system and its implications on hydrocarbon source rocks and accumulation were first identified. Algal bloom induced by subaqueous eruptions is the main cause for episodic deposition of organic matter and extreme heterogeneity in both lithofacies and source-rock distribution. The results suggest that cone-shaped buildups on seismic sections, which were formed by volcanic-hydrothermal deposits and contain highly-mixed feldspar and carbonate sediments, are the best hydrocarbon reservoirs, and demonstrate a strong relationship between volcanic-hydrothermal activities and hydrocarbon accumulation in an extensional tectonic setting. • Oil-bearing shales contain abundant volcanic-hydrothermal sediments. • Subaqueous volcanic-hydrothermal and lake sediments mixed in a rift basin. • Most quartz was precipitated from acidic-hydrothermal fluid before compaction. • Algae are the main organic matter and grew by volcanic-hydrothermal nutrients. • Lithofacies of mixed minerals near cone-shaped body on seismic are oil targets. [ABSTRACT FROM AUTHOR]

Emissions of PM 2.5 and trace gases from residential coal consumption for winter heating have caused severe air pollution in northern China. Clean coal briquettes can meet both demands of clean environment and residential heating. As a byproduct from the Bayer process, red mud has the potential to be used as briquettes additive, although its recycling procedure is challenging. In this study, red mud was used to replace the currently used calcium oxide as additive in coal briquetting. Twelve sets of combustion experiments were conducted for bituminous coal, anthracite coal and their briquettes, and each set of the experiment was repeated at least three times. Emission profiles of PM 2.5 , SO 2 and NO x were recorded during experiments. The highest emission reduction rates for PM 2.5 , SO 2 and NO x were achieved at red mud contents of 10%, 5% and 2.5%, respectively, for bituminous coal, and at 10%, 5% and 7.5%, respectively, for anthracite coal. The corresponding emission reduction rates were 37.5%, 25.8% and 61.9% for bituminous coal and 31.2%, 55.1% and 17.9% for anthracite coal. In addition, both SO 2 and NO x emissions showed clear peaks during the initial-burning stage for the two kinds of coals, while SO 2 emission for anthracite coal burning showed another peak during the char-burning stage. Benefit analysis was also conducted assuming all the currently used raw coals were replaced with clean coal briquettes in Shaanxi province. The overall reductions are 2270.46 (t) year−1 for PM 2.5 , 1538.00 (t) year−1 for SO 2 and 2177.81 (t) year−1 for NO x in the province. Results presented in this study highlight that development of clean energy policies, such as replacing bituminous coal and anthracite coal with clean coal briquettes, will be effective to improve the regional air quality. Image 1 • Clean coal briquette was made by using red mud as additive. • Emission profiles of PM 2.5 , SO 2 , NO x , and MCE were determined. • Briquette is effective on PM 2.5 , SO 2 , and NOx emission reduction. [ABSTRACT FROM AUTHOR]

• 10 typical residential heating scenarios were selected to measure the VOC emissions. • TVOC EFs follow the sequence of fuel wood > maize straw > bitumite > anthracite. • Significant difference in emission profiles were found between coal and biomass. • Clean combustion technologies could lead to over 90% TVOC emissions. Solid (biomass and coal) fuels burned for residential heating are major sources of atmospheric volatile organic compounds (VOCs). In this study, VOC samples were collected in-situ from chimneys in 10 typical heating scenarios in rural areas of the Guanzhong Plain. A modified SUMA canister approach was then employed, followed by gas chromatography/mass spectrometry analysis. Emission factors (EFs) (as received basis) of targeted non-methane VOCs (NMVOCs) varied from 90.3 ± 29.3 to 12300 ± 1510 mg kg−1 in descending order of fuel wood > maize straw > bitumite ≫ anthracite (p < 0.05). Both clean stove and coal briquetting technologies effectively reduced VOC EFs compared with traditional heating methods. The EFs of methane (CH 4) had similar characteristics to those of NMVOCs. However, they yielded different correlations with CO because of their differing mechanisms of formation. Coefficient of divergence (CD) values showed that a semi-gasifier has a limited effect on changing VOC profiles compared with a traditional stove using the same fuels. However, different types of fuel produce CD values over 0.50, which should therefore be classified as different sub-categories in source apportionment models. Correlation analysis showed that volatile matter content (V%) and modified combustion efficiency (MCE) were the two primary factors influencing NMVOC and CH 4 emissions. A stepwise linear regression analysis showed that V%, MCE, and element nitrogen content (N%) can be used to predict total VOC (TVOCs, including CH 4 and NMVOCs) emissions with regression coefficients of 0.23, −72.8 and −6.53, respectively (R2 = 0.92, p < 0.001). Ozone formation potential (OFP) EFs from burning solid fuel ranged from 72 to 18680 mg kg−1, with an approximate 50% contribution from alkenes. VOCs from burning solid fuel were equivalent to 62 to 22200 mg kg−1 secondary organic aerosol formation potential (SOAP), most of which (>95%) were contributed by aromatics. A semi-gasifier and coal briquettes were effective in reducing TVOC emissions, even when used in conjunction with a traditional stove and fuels. It is estimated that over 15,000 ton year−1 emissions can be reduced in Guanzhong Plain by adopting a semi-gasifier and coal briquettes, resulting in a 57,000 and 65,000 ton year−1 reduction of OFP and SOAP emissions, respectively. These results demonstrate that the use of clean heating technologies in Guanzhong Plain has considerable potential in relation to emissions reduction and thus provides a feasible solution to mitigate VOCs and related secondary pollutants emitted by residential solid fuel burning. [ABSTRACT FROM AUTHOR]