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Adenosine (Ado) drives immune suppression in the tumor microenvironment. In this issue of Cancer Cell , Klysz et al. investigate Ado-mediated immunosuppression. Overexpression of Ado deaminase (ADA-OE), metabolizing Ado to inosine (INO), induces stemness and improves CAR T cell functionality. Likewise, exposure to INO enhances CAR T cells' function and induces stemness features. [ABSTRACT FROM AUTHOR]

A conductive engineered cardiac patch (ECP) can reconstruct the biomimetic regenerative microenvironment of an infarcted myocardium. Direct ink writing (DIW) and 3D printing can produce an ECP with precisely controlled microarchitectures. However, developing a printed ECP with high conductivity and flexibility for gapless attachment to conform to epicardial geometry remains a challenge. Herein, an asymmetrical DIW hydrophobic/hydrophilic membrane using heat‐processed graphene oxide (GO) ink is developed. The "Masked spin coating" method is also developed that leads to a microscale GO (hydrophilic)/reduced GO (rGO, hydrophobic) physiological sensor, as well as a macroscale moisture‐driven GO/rGO actuator. Depositing mussel‐inspired polydopamine (PDA) coating on the one side of the DIW rGO , the ultrathin (approximately 500 nm) PDA‐rGO (hydrophilic)/rGO (hydrophobic) microlattice (DrGOM) ECP is bestowed with the flexibility and moisture‐responsive actuation that allows gapless attachment to the curved surface of the epicardium. Conformable DrGOM exhibits a promising therapeutic effect on rats' infarcted hearts through conductive microenvironment reconstruction and improved neovascularization. [ABSTRACT FROM AUTHOR]

As the second most predominant greenhouse gas, methane-targeted emission mitigation holds the potential to decelerate the pace of global warming. Satellite remote sensing is an important monitoring tool, and we review developments in the satellite detection of methane. This paper provides an overview of the various types of satellites, including the various instrument parameters, and describes the different types of satellite retrieval algorithms. In addition, the currently popular methane point source quantification method is presented. Based on existing research, we delineate the classification of methane remote sensing satellites into two overarching categories: area flux mappers and point source imagers. Area flux mappers primarily concentrate on the assessment of global or large-scale methane concentrations, with a further subclassification into active remote sensing satellites (e.g., MERLIN) and passive remote sensing satellites (e.g., TROPOMI, GOSAT), contingent upon the remote sensing methodology employed. Such satellites are mainly based on physical models and the carbon dioxide proxy method for the retrieval of methane. Point source imagers, in contrast, can detect methane point source plumes using their ultra-high spatial resolution. Subcategories within this classification include multispectral imagers (e.g., Sentinel-2, Landsat-8) and hyperspectral imagers (e.g., PRISMA, GF-5), contingent upon their spectral resolution disparities. Area flux mappers are mostly distinguished by their use of physical algorithms, while point source imagers are dominated by data-driven methods. Furthermore, methane plume emissions can be accurately quantified through the utilization of an integrated mass enhancement model. Finally, a prediction of the future trajectory of methane remote sensing satellites is presented, in consideration of the current landscape. This paper aims to provide basic theoretical support for subsequent scientific research. [ABSTRACT FROM AUTHOR]

The alternating direction method of multipliers (ADMM) is a classical effective method for solving two-block convex optimization subject to linear constraints. However, its convergence may not be guaranteed for multiple-block case without additional assumptions. One remedy might be the block-wise ADMM (BADMM), in which the variables are regrouped into two groups firstly and then the augmented Lagrangian function is minimized w.r.t. each block variable by the following scheme: using a Gauss–Seidel fashion to update the variables between each group, while using a Jacobi fashion to update the variables within each group. In order to derive its convergence property, a special proximal term is added to each subproblem. In this paper, we propose a new partial PPA block-wise ADMM where we only need to add proximal terms to the subproblems in the first group. At the end of each iteration, an extension step on all variables is performed with a fixed step size. As the subproblems in the second group are unmodified, the resulting sequence might yield better quality as well as potentially faster convergence speed. Preliminary experimental results show that the new algorithm is empirically effective on solving both synthetic and real problems when it is compared with several very efficient ADMM-based algorithms. [ABSTRACT FROM AUTHOR]

The positive trend of tropospheric column ozone (TCO) in China has been confirmed by numerous observations, particularly in the rapidly developing city clusters such as Beijing-Tianjin-Hebei (BTH), the Yangtze River Delta (YRD) and the Pearl River Delta (PRD). An unignorable but poorly known function may be played by the Brewer-Dobson circulation (BDC) and the Hadley circulation (HC), both of which are in their strengthening phase. This study discusses their connection to TCO in these three city clusters based on a novel and powerful causal analysis method Convergent Cross Mapping (CCM). It revealed that both BDC and HC exerted substantial causal effects on the variations of the TCO in BTH, the YRD, and the PRD. The upwelling moving northward in the summer substantially lowered TCO in the PRD, contributing to the difference in the TCO annual cycle characteristics between northern and southern China. Besides, CCM distinguished that hemispheric HC impacts TCO greatly more than total HC, and the most essential branches of BDC were stratospheric or shallow branches. The BDC and HC indices determined by CCM were used for building a multiple linear regression model, which assessed their importance for long-term changes in regional TCO. The intensity of BDC is the most important influencing factor in each region, particularly in the YRD. BTH is mainly affected by the intensity of the two meridian circulations. The influence of the widths of meridional circulation upwellings on TCO in the PRD cannot be ignored. Furthermore, TCO displayed significant positive trends during 2005–2020, with rates of 2.3 ± 0.4, 2.5 ± 0.4, and 2.7 ± 0.5 DU/decade in BTH, the YRD, and the PRD, respectively. • BDC and HC contribute to the different annual cycle patterns of TCO in northern and southern China. • Hemispheric HC impacts TCO greatly more than total HC. • The upwelling moving northward in the summer substantially lowered TCO in the PRD • TCO showed positive trends of around 2.5 DU/decade in China from 2005 to 2020 [ABSTRACT FROM AUTHOR]

Conductive cardiac patches, conformable printed cardiac patches, direct ink writing, myocardial infarction, ultra-thin microlattices Keywords: conductive cardiac patches; conformable printed cardiac patches; direct ink writing; myocardial infarction; ultra-thin microlattices EN conductive cardiac patches conformable printed cardiac patches direct ink writing myocardial infarction ultra-thin microlattices 1 1 1 08/10/23 20230808 NES 230808 B Direct Ink Writing b In article number 2300866, Leyu Wang, Malcolm Xing, and co-workers prepare, printed graphene oxide (GO)/reduced GO bilayer membrane for asymmetric structure with hydrophobicity and hydrophilicity on two sides, leading to multifunctional applications in conformable ultra-thin cardiac patches, moisture-responsive soft robots, and wearable electronics. Development of an Asymmetric Hydrophobic/Hydrophilic Ultrathin Graphene Oxide Membrane as Actuator and Conformable Patch for Heart Repair (Adv. Funct. [Extracted from the article]

Abstract The novel carbon-fenced conductive silver nanowires-supported hierarchical polyaniline nanowires have been successfully designed to exploit the synergistic effect for electrochemical energy storage. The electronic conductive hybrid polyaniline@carbon@silver nanowires nanocomposite electrode leads to a high specific capacity (785 C/g at 0.5 A/g) and good cycling stability (94.1% after 3000 cycles) compared with the electrode without silver nanowires, and it is also superior or close to some polyaniline-based materials. The presence of silver nanowires on hierarchical polyaniline nanowires may provide a least resistance path to electrons, which can accelerate electron transport between the current collector and the active material to enhance the specific capacity. The carbon shell fenced on conductive silver nanowires can be served as a good physical substrate to promote the polyaniline growth with well-defined hierarchical structure, and hold the polyaniline fragments together and maintain their electrochemical stability during charge-discharge process. The excellent electrochemical behavior is in combination with the ideal form of hierarchical architecture, which suggests that the as-prepared polyaniline@carbon@silver nanowires electrode has the significant potential to be used as a promising electrode material for lightweight and flexible energy storage devices. Graphical abstract The novel carbon-fenced conductive silver nanowires-supported hierarchical polyaniline nanowires (i.e. PANI@C@AgNWs) have been successfully designed to exploit the synergistic effect for electrochemical energy storage. The electronic conductive hybrid PANI@C@AgNWs nanocomposite electrode leads to a high specific capacity (785 C/g at 0.5 A/g) and good cycling stability (94.1% after 3000 cycles) compared to the electrode without AgNWs, and it is also superior or close to some individual PANI nanostructures and PANI composite materials. Image 1 Highlights • The carbon-fenced Ag nanowires-supported hierarchical PANI nanowires is designed. • The carbon and Ag nanowire is exploited the synergistic effect for PANI electrode. • The specific capacity of 785 C/g was obtained when PANI acted as the electrode. • The cycling stability with capacity retentions of 94.1% after 3000 cycles. [ABSTRACT FROM AUTHOR]

This study presents a novel bus charging station planning problem considering integrated photovoltaic (PV) and energy storage systems (PESS) to smooth the carbon‐neutral transition of transportation. This paper illustrates a two‐stage stochastic programming model capturing the uncertainty of PV power outputs and designs a step‐wise solution approach in which a conventional charging station location problem is solved in the first step and an improved L‐shaped algorithm is developed in the second step to determine charging station locations with PESS. The numerical experiments indicate that the step‐wise solution approach can provide high‐quality solutions within acceptable computational time. A case study is performed using a real‐world transit network in Beijing, China, with 34 bus routes and 15 candidate bus charging stations. Compared with the benchmark model, both recharging cost and carbon emission are reduced considerably. This paper provides novel insights into the development of integrated transportation and renewable energy systems. [ABSTRACT FROM AUTHOR]

A high-accuracy surface modeling (HASM) method based on the fundamental theorem of surfaces, is developed to simulate XCO surfaces using the GOSAT retrieval XCO data. Two tests are designed to investigate the simulation accuracy. The first test divides the existing satellite retrieval XCO data into training points and testing points, and simulates the XCO surface using the training points while computing the simulation error using the testing points. The absolute mean error (MAE) of the testing points is 1.189 ppmv, and the corresponding values of the comparison methods, Ordinary Kriging, IDW, and Spline are 1.203, 1.301, and 1.355 ppmv, respectively. The second test simulates the XCO surface using all the satellite retrieval points and uses the TCCON (Total Carbon Column Observing Network) site observation values as the ture values. For the six typical TCCON sites, the HASM simulation MAE is 1.688 ppmv, and the satellite retrieval MAE at the same sites is 2.147 ppmv. These results indicate that HASM can successfully simulate XCO surfaces based on satellite retrieval data. [ABSTRACT FROM AUTHOR]

Chimeric antigen receptor (CAR) T cell therapy has limited efficacy against solid tumors, and one major challenge is T cell exhaustion. To address this challenge, we performed a candidate gene screen using a hypofunction CAR-T cell model and found that depletion of basic leucine zipper ATF-like transcription factor (BATF) improved the antitumor performance of CAR-T cells. In different types of CAR-T cells and mouse OT-1 cells, loss of BATF endows T cells with improved resistance to exhaustion and superior tumor eradication efficacy. Mechanistically, we found that BATF binds to and up-regulates a subset of exhaustion-related genes in human CAR-T cells. BATF regulates the expression of genes involved in development of effector and memory T cells, and knocking out BATF shifts the population toward a more central memory subset. We demonstrate that BATF is a key factor limiting CAR-T cell function and that its depletion enhances the antitumor activity of CAR-T cells against solid tumors. [Display omitted] • Development of an in vitro CAR-T cell hypofunction model for genetic screen • BATF depletion enhances CAR-T cells efficacy against solid tumors • BATF drives CAR-T cell exhaustion by binding to and upregulating related genes • BATF editing induces formation of more central memory CAR-T cells Zhang et al. establish an in vitro CAR-T cell hypofunction model and identify that BATF drives T cell exhaustion and represses formation of a central memory subset by binding to and regulating related genes in CAR-T cells. Depletion of BATF enhances the antitumor activity of CAR-T cells against solid tumors. [ABSTRACT FROM AUTHOR]

With the fast development of economy and industry in the past thirty years, many large cities in the eastern and southwestern areas of China are experiencing increased haze events and atmospheric pollution, which causes significant impacts on the regional environment, human health, and even climate. The long-term trend and spatiotemporal variations of haze over China during recent 30 years are investigated using TOMS AAI products. In addition, the heavy haze events that occurred in January 2013 over eastern China are explored using AAI products from TOU on board FY-3A. Validation results show that satellite AAI products can be used for haze monitoring since it is sensitive to the carbonaceous aerosol, which is one of the main components of haze. In China, the high AAI values (>1.0) mainly located in the main four areas with intense anthropogenic activities, except for the desert region in Northwestern China. In the eastern and northeastern region, AAI peaks dominate in spring before 2005 since those areas were always affected by dust in spring. However, after 2005, AAI peaks appear in winter over eastern China because of haze. Moreover, in the northeastern region, AAI peaks dominate in winter with a secondary peak in spring because this area is affected by both dust and haze. In the southern region, the AAI peaks always dominate in spring since the high-level air pollution often occur in spring, but a decreasing trend is acquired during recent ten years. Over eastern China and northeastern China, AAI shows an increasing trend during recent 30 years in winter, which reveals that the haze over these areas is strengthen. A case study result shows that the heavy haze events occurred in January 2013 in eastern China can be clearly identified from the AAI products of TOU/FY-3A. The daily coverage area with AAI > 3.0 peaks at five periods at this time, i.e. Jan. 7–8, Jan. 13, Jan. 18, Jan. 23, and, Jan. 28–29, which agrees well with the haze events recorded by in-situ measurements. [ABSTRACT FROM AUTHOR]

Observations from space were used to evaluate the effect of emission control measures on the changes of air pollutants in Beijing and its surroundings during the 2014 Asia-Pacific Economic Cooperation (APEC) Summit held in Beijing. Compared to the past three years (2011–2013), NO 2 tropospheric vertical column densities in 2014 were found to exhibit almost across-the-board significant reductions over the North China Plain, suggesting the effectiveness of the national policy on NOx emission reduction during China's 12th “Five-Year-Plan”. During the APEC period (Nov. 3–11), AOD and AAOD were found reduced the most in Beijing, followed by Hebei province. Stringent emission control measures implemented in Beijing and the regional joint control over the surroundings especially in Hebei were responsible for the good air quality and so-called “APEC Blue”. However, air quality plummeted during the post-APEC period (Nov. 12–30), which was largely related to the lifting of local and regional joint emission control measures. By applying a spatial correlation analysis method, the potential emission source regions impacting air quality of Beijing included widespread areas in Hebei, Shandong, Shanxi, and Tianjin in the past three years (2011–2013). While during the study period in 2014, areas impacting Beijing evidently shrank and were limited within Hebei, suggesting evident effects of intense emission perturbations on lowering the extent of regional transport. This study indicates short-term measures did fix the air pollution problems in China but a permanent solution is still a tremendous challenge. [ABSTRACT FROM AUTHOR]

Based on the optimal estimation method, a satellite XCO retrieval algorithm was constructed by combining LBLRTM with VLIDORT. One-year GOSAT/TANSO observations over four TCCON stations were tested by our algorithm, and retrieval results were compared with GOSAT L2B products and ground-based FTS measurements. Meanwhile, the influence of CO line mixing effect on retrieval was estimated, and the research showed that neglecting CO line mixing effect could result in approximately 0.25% XCO underestimation. The accuracy of XCO retrievals was similar to GOSAT L2B products at cloud-free footprints with aerosol optical depth less than 0.3, and 1% accuracy of XCO retrievals can be reached based on the validation result with TCCON measurements. [ABSTRACT FROM AUTHOR]

The East Asian summer monsoon (EASM) was extremely strong in 2018, which substantially affected surface ozone (O3) in China. Taking 2018 and the average synthesis of 2003 and 2010 to represent the strong and weak EASM cases, respectively, GEOS-Chem with constant anthropogenic emission was employed to investigate the impact of the EASM on surface O3 in the east of China. Simulations show that surface O3 decreased in the northeast and the eastern coast of China and increased in most of the remaining regions during strong EASM. The difference in surface O3 between strong and weak EASM was around −15~7 ppbv. After analyzing relevant meteorological fields, it is found that the decrease in northeast China was mainly attributed to the large increase in vertical upward transport. The considerable decrease in the Huang-Huai-Hai region depended on the dilution and diffusion of eastward anomalous horizontal circulation. The increase in Hunan-Hubei-Guangdong Province was largely due to input from the north. In addition, the vast areas between the Yangtze River and the Yellow River were supported by higher temperatures and stronger shortwave solar radiation that promoted photochemical reactions. The reasons for changes in Shanxi-Sichuan-Yunnan Province were relatively more complex and thus require more in-depth exploration. [ABSTRACT FROM AUTHOR]

Synopsis: Smart farming system is built by a versatile conductive hydrogel: clean energy sources can be harvested by our nano energy generator device and stored in the hydrogel supercapacitors to power up the light fertilizer for plant growth promotion, which is monitored by the wireless wearable sensors. [Display omitted] • Multifunctional hydrogel for plant (vegetable, fruits) wearable sensor. • Self-powered hydrogel for green agriculture. • Hydrogel sensor monitoring and promoting fruit growth. • The gel collecting energy from wind, rain and sounds for light "fertilizer". • Plant-device interaction on the gel. Significant energy is consumed to produce the highest-yielding agriculture, which increases greenhouse gas emission and leads to climate change. Smart farming is expected to allow to enhance efficiency and sustainability via site-specific monitoring and managing of crops. This study is a first of its kind development of versatile double-network hydrogel that can serve as: 1) a clean energy harvesting device for self-powered light fertilizer for plants, 2) a supercapacitor for energy storage, 3) plant growth sensor, and 4) an ammonia sensor. Polyacrylic acid double-networked with the conductive nanofiller reduced graphene oxide and then coated with polyaniline are incorporated with double networking (PAA-RGO-PANI, PRP) that significant improved mechanical stress from 300 KPa to 1050Kpa. The excellent stretchability (650%) and strength makes it suitable for agriculture-purposed plant-wearable senor that satisfies the plant growth. The electrical performance of the triboelectric energy harvester (PRP-TENG) provides high power density at 424 mW/m2 from sound wave, wind, and mechanic pressure. The PAA-RGO-PANI supercapacitor can maintain a stable capacitance at 2330 mF cm−2 after 5000 cycles. The self-powered system combined with PRP-TENG and supercapacitor shows great potential in modern agriculture system. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents results of measurements of tropospheric sulphur dioxide (SO2) from satellite over China during 2004–2009. SCIAMACHY/ENVISAT SO2 data products have been validated by ground based remote sensing instrument MAXDOAS in China, and with predictions of the atmospheric model GEOS–Chem. The spatial and temporal distribution of tropospheric SO2 over China is discussed in this study. The result shows that the SO2 load over East China is decreasing since strong control for pollution emission in 2007 for preparation of 2008 Olympic Games in China, while the SO2 load in West China is increasing all the way during 2004–2009, which might reflect that the anthropogenic activity was added to promote the economy development in west of China. Typical seasonal variation with high pollution levels in winter and low in summer is found in the northwest of China, while the inverse seasonal variation is found for the south of China. The characteristics of tropospheric SO2 over the major cities in China were explored and found that tropospheric SO2 was partly under control from 2007 because of the policy from China government for reduction in SO2 emissions in 2006. And the SO2 value shows remarkably decrease in most of the major cities after 2007 because strong control for the pollution emission for 2008 Olympic games. Guangzhou city shows high SO2 pollution levels in summer time, since most of the coal power plants and thermal power industry are located to the south of Guangzhou city and southerly winds dominate during summer time. [Copyright &y& Elsevier]

Spaceborne measurements by the Atmospheric Infrared Sounder (AIRS) on the EOS/Aqua satellite provide a global view of methane (CH) distribution in the mid-upper troposphere (MUT-CH). The focus of this study is to analyze the spatiotemporal variations in MUT-CH over China from 2003 to 2008. Validation of AIRS CH4 products versus Fourier transform infrared profiles demonstrates that its RMS error is mostly less than 1.5%. A typical atmospheric methane profile is found that shows how concentrations decrease as height increases because of surface emissions. We found that an important feature in the seasonal variation in CH4 is the two peaks that exist in summer and winter in most parts of China, which is also observed in in-situ measurements at Mt. Waliguan, Qinghai Province, China (36.2879°N 100.8964°E, 3810 m). Also, in the summer, only one peak existed in western and southern China since there are no more significant anthropogenic sources in winter than at any other time of the year. Further analysis of the deseasonalized time-series of AIRS CH4 in three fixed pressure layers of AIRS from 2003 to 2008 indicates that CH4 in the Northern Hemisphere has increased abruptly since 2007, with no significant increase occurring before 2007. The increase in China is generally more significant than in other areas around the world, which again correlates with in-situ measurements at Mt. Waliguan. [ABSTRACT FROM AUTHOR]

The first 18 months of data from the FY-3A Total Ozone Unit (FY-3A/TOU) was collected to analyse instrument performance. Retrieval tests were carried out using post-launch calibration coefficients. Validation was analysed at 74 ground-based stations of total ozone network by inter-comparison with AURA/Ozone Monitoring Instrument (OMI) Total Ozone Mapping Spectrometer (TOMS) V8 data and comparison with ground-based measurements. The validation results show that the TOU total column ozone has an average root mean square (rms) error of less than 3.1% compared with OMI products, and less than 4.4% compared with ground-based measurements. The solar irradiance is measured continuously, and the post-launch calibration coefficients will be updated only if the change of instrument sensitivity has noticeable influence on the retrieval. The instrument is currently stable. [ABSTRACT FROM PUBLISHER]

Mid-troposphere CO2 data retrieved by the AIRS (atmospheric infrared sounder) were validated with five ground-based stations and aircraft measurements in the Northern Hemisphere. AIRS CO2 products show good agreement with ground and aircraft observations. The data had a monthly average accuracy better than 3 ppmv. In this study, the spatial and temporal distribution of mid-troposphere CO2 from January 2003 to December 2008 was analyzed based on this satellite product. The average concentration of atmospheric CO2 was higher in the Northern Hemisphere than in the Southern Hemisphere. The yearly average results show a gradual increase from 2003 to 2008. In China, the annual growth rate was about 2 ppmv/a, similar to the United States, Europe, Australia and India, but was slightly lower than Canada and Russia. Mid-troposphere CO2 concentrations were higher over northern China than over southern areas, due to differences in natural conditions and industrial layout. There were four centers of high CO2 concentration between 35° and 45°N over China, with low concentrations over Yunnan Province. There was a significant seasonal CO2 variation with peak concentration in spring and the lowest concentration in autumn. [ABSTRACT FROM AUTHOR]

Retrieval experiment was made for global total column ozone using the first year measurements of Total Ozone Unit (TOU) on board the second generation polar orbiting meteorological satellite of China, FY-3/A. The retrieval results were analyzed and validated by comparison with AURA/OMI, Meteop/GOME-2 global ozone products and ground-based ozone measurement data. The qualititative comparisons over the globe especially over Antarctica and the Tibetan Plateau show that the spatial and temporal distribution characteristics are consistent with OMI and GOME-2 products. The quantitative comparisons with ground-based measurements and AURA/OMI ozone product were made over 74 stations, the TOU total ozone retrieval has a 3% rms relative error compared with AURA/OMI ozone product and 4.2% rms relative error with ground-based measurements. The maximum difference between satellite retrieval and ground-based measurements was found in the Antarctica ozone hole. The TOU global ozone product is operational and distributed to all users. [ABSTRACT FROM AUTHOR]

Atmospheric transport of trace elements has been found to be an important pathway for their input to the ocean. TSP, PM10, and PM2.5 aerosol samples were collected over the Northern South China Sea in two cruises in 2003 to estimate the input of aerosol from continent to the ocean. About 23 elements and 14 soluble ions in aerosol samples were measured. The average mass concentration of TSP in Cruise I in January (78μgm−3) was ∼twice of that in Cruise II in April (37μgm−3). Together with the crustal component, heavy metals from pollution sources over the land (especially from the industry and automobiles in Guangzhou) were transported to and deposited into the ocean. The atmospheric MSA concentrations in PM2.5 (0.048μgm−3 in Cruise I and 0.043μgm−3 in Cruise II) over Northern South China Sea were comparable to those over other coastal regions. The ratio of non-sea-salt (NSS)-sulfate to MSA is 103-655 for Cruise I and 15-440 for Cruise II in PM2.5 samples, which were much higher than those over remote oceans. The estimated anthropogenic sulfate accounts for 83–98% in Cruise I and 63–95% in Cruise II of the total NSS-sulfate. Fe (II) concentration in the aerosols collected over the ocean ranged from 0.1 to 0.9μgm−3, accounting for 16–82% of the total iron in the aerosol, which could affect the marine biogeochemical cycle greatly. [Copyright &y& Elsevier]

The specification of the dements on the surface of the particles collected during dust storm and non-dust storm in Beijing and Inner Mongolia was studied by XPS. The major species of iron on the surface were oxides, sulfate, silicate, FeOOH and minor part sorbed on SiO2/Al2O3. Sulfate is the dominant species of sulfur on the surface. SiO2 and Al2O3 are the main components of Si and Al on the surface respectively. One of the most important findings was that the Fe(II) (FeS and FeSO4) produced could account for up to 44.3% and 45.6% of the total Fe on the surface in the aerosol sample collected at that night and next day of the ‘peak’ time of the dust storm occurring on March 20, 2002, while Fe2(SO4)3, one of the Fe(III) species on the surface decreased from 67.1% to 49.5% and 48.0% respectively. Both S and Fe enriched on the surface of aerosol particles. Fe(II) accounted for 1.3%–5.3% of total Fe in bulk aerosol samples during dust storm. These results provided strong evidence to support the hypothesis of the coupling, between iron and sulfur in aerosols during the long-range transport, which would have important impact on the global biogeochemical cycle. [ABSTRACT FROM AUTHOR]

Atmospheric carbon dioxide (CO2) is recognized as the most important component of the greenhouse gases, the concentration of which has increased rapidly since the pre-industrial era due to anthropogenic emissions of greenhouse gases (GHG). The accurate monitoring of carbon dioxide is essential to study the global carbon cycle and radiation budget on Earth. The Aerosol and Carbon Detection Lidar (ACDL) instrument onboard the Atmospheric Environmental Monitoring Satellite (AEMS) was successfully launched in April 2022, which allows a new perspective to quantify the global spatial distribution of atmospheric CO2 with high accuracy. In this work, the impact of the Doppler shift on CO2 measurements for an integrated-path differential absorption (IPDA) light detection and ranging (lidar) system was evaluated to meet the weighted column-averaged mixing ratio of carbon dioxide (XCO2) measurement requirements of less than one part per million (ppm). The measurement uncertainties due to the Doppler shift were first evaluated in airborne IPDA observations. The result shows that most of the Doppler shift is in the range of 6–8 MHz, resulting in 0.26-0.39 ppm deviations in the XCO2 results. The deviations between the XCO2 retrievals and in situ measurements decreased to 0.16 ppm after the correction of the Doppler shift from 11:28:29 to 11:28:49 in the flight campaign. In addition, the online Doppler shift accounts for 98% of the deviations between XCO2 retrievals and in situ measurements. Furthermore, the impact of the Doppler shift on ACDL measurements is also assessed. The differences between the XCO2 retrievals with and without Doppler shift are used to quantify measurement uncertainties due to the Doppler effect. The simulations reveal that a pointing misalignment of 0.067 mrad can lead to a mean bias of about 0.30 ppm (0.072%) in the CO2 column. In addition, CO2 measurements are more sensitive to the Doppler shift at high altitudes for IPDA lidar, so the largest differences in the CO2 columns are found on the Qinghai–Tibet Plateau in China. [ABSTRACT FROM AUTHOR]

China is likely the world's largest anthropogenic source of methane emissions, with coal mine methane (CMM) being the predominant contributor. Here, we deploy 2 years of satellite observations to survey facility‐level CMM emitters in Shanxi, the most prolific coal mining province in China. A total of 138 detected episodic events at 82 facilities are estimated to emit 1.20 (+0.24/−0.20, 95% CI) million tons of methane per year (Mt CH4/yr) during 2021–2023, roughly equivalent to 4.2 times the integrated flux from the Permian plumes and four times of the integrated flux from the Four Corners plumes, two of the world's largest hotspots for oil and gas methane emissions. This work reveals the heavy‐tailed distribution characteristic of CMM emission sources for the first time, with 20% of emitters contributing approximately 50% of total emissions. Comparison with the Global Energy Monitor (GEM) inventory reveals that the GEM estimate is about 4.1 times our estimate. Plain Language Summary: This study examines methane emissions from coal mines in Shanxi, China, identified as a significant source of global methane, a potent greenhouse gas. Using satellite data over 2 years, we found 138 detected episodic events at 82 facilities in Shanxi emitting an estimated 1.2 million tons of methane annually, far exceeding emissions from known global hotspots in the oil and gas sectors. Our analysis shows that a small percentage of these facilities contribute to the majority of emissions. The results, which challenge previous estimates from environmental monitoring organizations, underscore the need for direct, observational methods to accurately assess and address methane emissions. This work aims to guide efforts in mitigating climate change by identifying key areas for reducing methane release. Key Points: Satellite data identify 82 major methane emitters in Shanxi, China, with high annual emissions of up to 1.2 MtTop 20% of coal mines contribute to half of the region's total methane emissionsFindings highlight the importance of direct measurements for accurate emission estimates [ABSTRACT FROM AUTHOR]

The variations of atmospheric compositions (ACs) can change the atmospheric interactions with other parts of the ecosystem, and it also affects the energy budget of the Earth. Satellite remote sensing plays a crucial role in monitoring AC by providing a matchless global perspective with consistency over long periods. Although China started space exploration missions in the early 1970s, the situation of lacking operational AC satellite missions was turned around until the launch of FY-3A in 2008. In the following decade, more Chinese pathfinder AC satellite missions were putting into operation, and then lead to a boom in related researches on air quality, trace gases and greenhouse gases (GHG) measurements. In particular, moderate resolution imageries of polar mission FY-3 series are used to monitor air quality, and recent comparable imagery onboard geostationary mission FY-4A could provide similar air pollution observation with higher temporal resolution of up to five minutes. Nadir spectrographs onboard FY-3 series and the latest pathfinder mission GF-5 aims to monitor various trace gases. Moreover, hyper-spectrometers onboard GF-5 and another pathfinder mission TanSat are devoted to mapping the global distribution of GHG, as a supplement to operational mission FY-3D. Besides the progress in the space-borne part, the in-situ calibration and validation have achieved fruitfully since the late 1990s, gaining insight into the consistency between the satellite and in-situ observations over China. Applications and studies based on Chinese satellite missions are still growing since it has only been a few years after their launch. Furthermore, the newly planned missions for monitoring AC with active remote sensing instruments are also illustrated, such as lidar, which will be able to improve the accuracy of space-borne observations. • Space-borne programs of China aiming to detect changes of atmospheric composition were reported in this review. • All the Chinese remote sensing programs inculuding operational meteorological satellites series(FY-3/FY-4), pathfinder programs (TANSat, GF-5) and their payloads were briefly introduced. And the instruments were classified by their capability for monitoring aerosol, greenhouse gases and trace gases. • Chinese ground station networks for calibration and vilidation of remote sensed atmospheric composition products were also reported, as well as their typical applications. • China's future remote sensing satellite to enhance capability of the atmospheric composition detection were briefed. [ABSTRACT FROM AUTHOR]

Satellite observation is one of the main methods used to monitor the global distribution and variation of atmospheric carbon dioxide (CO2). Several CO2 monitoring satellites have been successfully launched, including Japan's Greenhouse Gases Observing SATellite (GOSAT), the USA's Orbiting Carbon Observatory-2 (OCO-2), and China's Carbon Dioxide Observation Satellite Mission (TanSat). Satellite observation targeting the ground-based Fourier transform spectrometer (FTS) station is the most effective technique for validating satellite CO2 measurement precision. In this study, the coincident observations from TanSat and ground-based FTS were performed numerous times in Beijing under a clear sky. The column-averaged dry-air mole fraction of carbon dioxide (XCO2) obtained from TanSat was retrieved by the Department for Eco-Environmental Informatics (DEEI) of China's State Key Laboratory of Resources and Environmental Information System based on a full physical model. The comparison and validation of the TanSat target mode observations revealed that the average of the XCO2 bias between TanSat retrievals and ground-based FTS measurements was 2.62 ppm, with a standard deviation (SD) of the mean difference of 1.41 ppm, which met the accuracy standard of 1% required by the mission tasks. With bias correction, the mean absolute error (MAE) improved to 1.11 ppm and the SD of the mean difference fell to 1.35 ppm. We compared simultaneous observations from GOSAT and OCO-2 Level 2 (L2) bias-corrected products within a ±1° latitude and longitude box centered at the ground-based FTS station in Beijing. The results indicated that measurements from GOSAT and OCO-2 were 1.8 ppm and 1.76 ppm higher than the FTS measurements on 20 June 2018, on which the daily observation bias of the TanSat XOC2 results was 1.87 ppm. These validation efforts have proven that TanSat can measure XCO2 effectively. In addition, the DEEI-retrieved XCO2 results agreed well with measurements from GOSAT, OCO-2, and the Beijing ground-based FTS. [ABSTRACT FROM AUTHOR]

Conducting polymer nanoarray structures had attracted increasing attention as potential electrode materials in supercapacitor devices. In this article, the orderly and highly dense polyaniline (i.e., PANI) nanorod arrays had been successfully grown onto the surface of carbon nanofibers(i.e., CNFs) to form PANI@CNFs composite via a one step of facile chemical oxidation method. The specific capacity of the single PANI@CNFs composite electrode was 758 C/g and 720 C/g at current densities of 1.0 and 5.0 A/g, respectively, while the cycling stability could maintain 85% of the initial capacity after 1000 charge-discharge cycles. Furthermore, two pieces of PANI@CNFs composite electrodes were fabricated into a symmetric all-solid-state flexible supercapacitor device to drive small electronic equipments using polyvinyl alcohol-H 2 SO 4 hydrogel as solid electrolyte, while the normal filter paper acted as a separator. The as-prepared symmetric supercapacitor device had excellent electrochemical performance with specific capacitance of 285 F/g at a current density of 0.5 A/g. The maximum energy density was 10.04 Wh/kg at a power density of 225 W/kg and showed no obvious decrease in the performance with a bending angle of 45° or 90°. The as-prepared symmetric all-solid-state flexible supercapacitor device had good promising applications in small wearable electronics. The orderly and highly dense polyaniline nanorod arrays had been successfully grown onto the surface of carbon nanofibers via a one step of facile chemical oxidation method. The as-prepared symmetric supercapacitor device had excellent electrochemical performance with specific capacitance of 285 F/g at a current density of 0.5 A/g, and the maximum energy density was 10.04 Wh/kg at a power density of 225 W/kg. The as-prepared symmetric all-solid-state flexible supercapacitor device had good promising applications in small wearable electronics. Image 1 • Orderly and highly dense PANI nanorod arrays fenced onto the surface of CNFs was designed. • The specific capacity of 758 C/g was obtained when PANI@CNFs acted as the electrode. • The maximum energy density of PANI@ CNFs was 10.04 Wh/kg at a power density of 225 W/kg. • The small wearable electronics could be drove by the as-prepared all-solid-state flexible supercapacitor device. [ABSTRACT FROM AUTHOR]

Silver nanowires (i.e., AgNWs) can act as effective surface-enhanced Raman spectroscopy (i.e., SERS) substrates to detect small molecules. However, a lot of prepared AgNWs were often wrapped by polyvinylpyrrolidone (i.e., PVP) thin film to form an insulating layer to produce ill-defined AgNWs-PVP-AgNWs interface, limiting the plasmonic coupling among the stacked AgNWs. Herein, we reported a facile method in removal of PVP ligands from AgNWs for high performance and reusable SERS substrate. Sodium borohydride (NaBH 4) was used to completely remove the PVP ligands from the surface of AgNWs and produce a clean AgNWs-AgNWs interface that effectively enhances the localized surface plasmon resonance (i.e., LSPR) was produced, greatly improving the SERS activity of the AgNWs thin film. The SERS detection of rhodamine 6G (i.e., R6G) used with PVP AgNWs and without PVP AgNWs is 1.0 × 10-9 and 1.0 × 10-15 M, and the average enhancement factor (EF) is about 0.86 × 104 and 9.35 × 104, respectively. Moreover, the recyclable behavior of the AgNWs with several analyte molecules is much more interesting than that of the PVP@AgNWs. The SERS detection of AgNWs for R6G, the 3-mercaptopropionic acid (i.e., 3-MPA) and melamine with good recyclability in nanomolar and millimolar concentration can be easily detected. A facile method in removal of PVP ligands from AgNWs for high performance and reusable SERS substrate had been reported. Sodium borohydride (NaBH 4) was used to completely remove the PVP ligands from the surface of AgNWs and produce a clean AgNWs−AgNWs interface that effectively enhances the localized surface plasmon resonance, greatly improving the SERS activity of the AgNWs thin film. Image 1 • PVP ligands can be easily removed from the AgNWs by NaBH 4 solution. • The clean AgNWs−AgNWs interface can effectively enhance the LSPR. • The clean AgNWs film can act as effective and recyclable SERS substrate. [ABSTRACT FROM AUTHOR]

Horizontal visibility (HVIS) is a primary index used for assessing air quality. Although satellite images provide information regarding atmospheric aerosols, atmospheric visibility is not directly measured. In this paper, a deep learning approach is proposed to retrieve HVIS using moderate-resolution imaging spectroradiometer (MODIS) aerosol optical depth (AOD) data, the European Centre for Medium-Range Weather Forecasts reanalysis dataset, and ground-based visibility observations. The deep neural network model comprises a multi-layer unsupervised restricted Boltzmann machine (RBM) and a layer for supervised learning. The dropout mechanism was used in the training process to overcome the errors caused by over-fitting. The results demonstrate that the correlation coefficient values between HVIS observations and retrievals during training, pre-validating, and evaluation were 0.74, 0.723, and 0.697, respectively. The retrieved HVIS in Eastern China exhibited a north-to-south increasing trend, increasing and decreasing in summer and winter, respectively. In conclusion, the proposed model presents an effective and more reliable method for HVIS retrieval. However, the small samples, low AOD, low albedo, high total column water, high longitude, and the low vertical wind component at 10 m likely cause HVIS bias. [ABSTRACT FROM AUTHOR]

Graphene and its chemically exfoliated derivatives—GO and rGO—are the key members of graphene family materials (GFM). The atomically thick crystal structure and the large continuous π conjugate of graphene imparts it with unique electrical, mechanical, optical, thermal, and chemical properties. Although those properties of GO and rGO are compromised, they have better scalability and chemical tunability. All GFMs can be subject to noncovalent modification due to the large basal plane. Besides, they have satisfying biocompatibility. Thus, GFMs are promising materials for biological, chemical and mechanical sensors. The present review summarizes how to incorporate GFMs into different sensing system including fluorescence aptamer-based sensors, field-effect transistors (FET), and electrochemical sensors, as well as, how to covalently and/or non-covalently modify GFMs to achieve various detection purpose. Sensing mechanisms and fabrication strategies that will influence the sensitivity of different sensing system are also reviewed. [ABSTRACT FROM AUTHOR]

Atmospheric ammonia (NH3) is a chemically active trace gas that plays an important role in the atmospheric environment and climate change. Satellite remote sensing is a powerful technique to monitor NH3 concentration based on the absorption lines of NH3 in the thermal infrared region. In this study, we establish a retrieval algorithm to derive the NH3 column from the Hyperspectral Infrared Atmospheric Sounder (HIRAS) onboard the Chinese FengYun (FY)-3D satellite and present the first atmospheric NH3 column global map observed by the HIRAS instrument. The HIRAS observations can well capture NH3 hotspots around the world, e.g., India, West Africa, and East China, where large NH3 emissions exist. The HIRAS NH3 columns are also compared to the space-based Infrared Atmospheric Sounding Interferometer (IASI) measurements, and we find that the two instruments observe a consistent NH3 global distribution, with correlation coefficient (R) values of 0.28–0.73. Finally, some remaining issues about the HIRAS NH3 retrieval are discussed. [ABSTRACT FROM AUTHOR]

The freeze-drying process of Angelica sinensis (Oliv.) Diels was studied and evaluated. Using a single factor investigation, drying temperature and pressure were determined as the main factors affecting the drying process. The central composite design (CCD) combined with response surface method was employed to optimize the drying process. Optimal conditions were determined to be 52 Pa, 63 °C, and a slice thickness of 5 mm. Subsequently, samples were compared in terms of chemical constituents, microstructure, and in vitro absorption profiles under different drying operations. The freeze-drying process was effective for the preservation of ferulic acid (1.82 mg/g), Z-ligustilide (13.91 mg/g), and other compositions. The porous and loose characteristic structure enabled rapid release of ferulic acid (71%, 60 min) and Z-ligustilide (32%, 60 min). Therefore, the freeze-drying method is a reasonable and efficient drying method for the dehydration of A. sinensis. [ABSTRACT FROM AUTHOR]

Cell‐free materials that can transmit both mechanical and electrical stimulations provide a promising strategy for myoinjury repair. Skeletal muscle is sensitive to electrical stimulation (ES), and accordingly, materials are required to transmit the electrical signal while maintaining their elasticity to build the cellular communication network in denervated muscle for retarding muscle atrophy. Here, tannic acid functionalized with methacrylate group (TA–MA), dopamine, and hydrothermal reduction are employed in multistep base reduction to fabricate a polydopamine (PDA)/reduced graphite oxide (rGO) aerogel. This mussel‐inspired PDA/rGO aerogel possesses good conductivity, electromechanical stability, and appropriate Young's modulus, which are favorable for the growth and differentiation of C2C12 myoblasts. After the cell‐free PDA/rGO aerogel‐transplanted denervated muscle is loaded with cyclic ES for 3 weeks, the mean muscle fiber size increases by 90% and the maximum contraction force of denervated muscle elevates by 50%, accompanied with a slight inflammation infiltration in muscle. In conclusion, PDA/rGO aerogel is a safe and effective implant for retarding the disuse muscle atrophy. Methacrylic anhydride–tannic acid (TA–MA), dopamine (DOPA), graphite oxide, and hydrothermal reduction are employed to produce an ultralight conductive and elastic aerogel in a multistep base reduction process. This aerogel can provide a favorable microenvironment for myogenic differentiation, and its transplantation‐combined electrical stimulation (ES) is proven to be a safe and effective strategy for retarding disuse muscle atrophy. [ABSTRACT FROM AUTHOR]

Accurate global monitoring of carbon dioxide (CO2) is essential for understanding climate change and informing policy decisions. This study compares column-averaged dry-air mole fractions of CO2 (XCO2) between ACOS_L2_Lite_FP V9r for Japan's Greenhouse Gases Observing Satellite (GOSAT), OCO-2_L2_Lite_FP V10r for the USA's Orbiting Carbon Observatory-2 (OCO-2), and IAPCAS V2.0 for China's Carbon Dioxide Observation Satellite (TANSAT) collectively referred to as GOT, with data from the Total Carbon Column Observing Network (TCCON). Our findings are as follows: (1) Significant data quantity differences exist between OCO-2 and the other satellites, with OCO-2 boasting a data volume 100 times greater. GOT shows the highest data volume between 30–45°N and 20–30°S, but data availability is notably lower near the equator. (2) XCO2 from GOT exhibits similar seasonal variations, with lower concentrations during June, July, and August (JJA) (402.72–403.74 ppm) and higher concentrations during December, January, and February (DJF) (405.74–407.14 ppm). XCO2 levels are higher in the Northern Hemisphere during March, April, and May (MAM) and DJF, while slightly lower during JJA and September, October, and November (SON). (3) The differences in XCO2 (ΔXCO2) reveal that ΔXCO2 between OCO-2 and TANSAT are minor (−0.47 ± 0.28 ppm), whereas the most significant difference is observed between GOSAT and TANSAT (−1.13 ± 0.15 ppm). Minimal differences are seen in SON (with the biggest difference between GOSAT and TANSAT: −0.84 ± 0.12 ppm), while notable differences occur in DJF (with the biggest difference between GOSAT and TANSAT: −1.43 ± 0.17 ppm). Regarding latitudinal variations, distinctions between OCO-2 and TANSAT are most pronounced in JJA and SON. (4) Compared to TCCON, XCO2 from GOT exhibits relatively high determination coefficients (R2 > 0.8), with GOSAT having the highest root mean square error (RMSE = 1.226 ppm, <1.5 ppm), indicating a strong relationship between ground-based observed and retrieved values. This research contributes significantly to our understanding of the spatial characteristics of global XCO2. Furthermore, it offers insights that can inform the analysis of differences in the inversion of carbon sources and sinks within assimilation systems when incorporating XCO2 data from satellite observations. [ABSTRACT FROM AUTHOR]

Tropospheric ozone plays an important role in atmospheric processes. However, the acquisition of tropospheric ozone content from satellite observations is a crucial challenge for atmospheric pollution research. In this study, the 0.25° × 0.25° tropospheric ozone column products over China were determined from total ozone columns measured by the Ozone Monitoring Instrument (OMI) and ozone profiler of the Microwave Limb Sounder (MLS). Calculation results were then validated with similar satellite products, Electrochemical Concentration Cell (ECC) ozonesonde observations, and simulation results from the Regional Atmospheric Modelling System – Community Multiscale Air Quality Model (RAMS-CMAQ). Validations shows that OMI-MLS calculation results correlate well with ozonesonde data, the correlation coefficient reached to 0.92. Compared to RAMS-CMAQ, OMI-MLS presents consistent distribution and the correlation coefficients range from 0.52 to 0.82. [ABSTRACT FROM AUTHOR]

Abstract In this study, the method of hydrothermal synthesis is introduced to prepare the titanium dioxide (i.e.,TiO 2) tetragonal prism array on the conducting plane of fluorine-doped tin oxide (i.e., FTO), and then the polyaniline (i.e., PANI) is coated on the surface of TiO 2 array by normal chemical oxidation to form the PANI/TiO 2 shell/core nanoarray. The array architecture of PANI/TiO 2 composite is further confirmed by SEM, XPS, XRD, UV–vis and Raman spectroscopy. The regular array structure of PANI/TiO 2 can reduce the resistance of ionic diffuse and charge transfer via optimizing the ionic diffusion to obtain a lower impedance and higher specific capacitance. Compared with the individual component (PANI or TiO 2), the PANI/TiO 2 /FTO electrode possesses a higher specific capacitance as the supercapacitor electrode material. The maximum specific capacitances of 633 F/g at the rate of 10 mV/s and 781 F/g at the current density of 1 A/g are obtained in the PANI/TiO 2 /FTO electrode and it is superior or close to individual PANI or PANI-based materials. In addition, the TiO 2 array can undertake some mechanical deformation in the redox process without destroying the electrode material to enhance the cyclic stability of PANI/TiO 2 /FTO electrode. The capacitance retention of PANI/TiO 2 /FTO electrode keeps 75% of its initial value which is higher than that of the PANI/FTO electrode (65%) after 2000 cycles. Therefore, such array architecture composite can be promisingly used as the electrode material for electrochemical capacitive energy storage. Graphical abstract The array architecture of PANI/TiO 2 shell/core composite was successful prepared onto the conducting plane of ITO. The PANI/TiO 2 shell/core array can reduce the resistance of ionic diffuse and charge transfer via optimizing the ionic diffusion to obtain lower impedance and a higher specific capacitance. The maximum specific capacitance of 633 F/g at rate of 10 mV/s and 781 F/g at 1 A/g are obtained in the PAN/TiO 2 /FTO electrode and it is superior or close to individual PANI or PANI-based materials. Image 10723 Highlights • The PANI/TiO 2 shell/core array was successful prepared onto the conducting plane of the ITO. • The specific capacitance of 781 F/g was obtained when PANI/TiO 2 acted as the electrode. • The cycling stability with capacitance retentions of 75% after 2000 cycles. • The PAN/TiO 2 shell/core array can reduce the resistance of ionic diffuse and charge transfer. [ABSTRACT FROM AUTHOR]

The high sensitivity and reproducibility are significant for the routine Surface-enhanced Raman Scattering (SERS) detection. Here, the pyramid-shape silver microstructures has been successfully synthesized using a facile electrochemical deposition method and the reaction with a two-indium tin oxides (ITO) electrode system is carried out by potentiostatic method, where only silver nitrate (AgNO 3 ) and poly (methyl methacrylate) (PMMA) nanospheres are introduced to control the reaction process. Meanwhile, PMMA nanospheres as morphology controlled reagents are used to lead Ag units to grow in the form of pyramid-shape. The prepared pyramid-shape silver microstructures possesses high SERS activity with an average enhancement factor ( EF ) of 9.1 × 10 5 , which is superior or close to some individual Ag or Au microstructures and Ag composite materials. In addition, an excellent reproducibility is achieved resulting from a relative standard deviation of 7.9%, 8.5%, 7.3%, and 8.7% measured by four Raman shifts of R6G at 612, 772, 1363, and 1650 cm −1 , respectively, which is much lower than those of the commonly used SERS substrates. Importantly, the as-prepared pyramid-shape silver microstructures have been evolved as a sensitive SERS substrate for the detection of trace amounts of rhodamine 6G (R6G) and 3-mercaptopropionic acid (3MPA) down to nanomolar and millimolar concentration with excellent recyclability. Therefore, this work offers a simple way to prepare pyramid-shape silver microstructures as an effective SERS substrate and make the SERS more practicable. [ABSTRACT FROM AUTHOR]

Black carbon (BC) has importance regarding aerosol composition, radiative balance, and human exposure. This study adopted a backward-trajectory approach to quantify the origins of BC from anthropogenic emissions (B C An) and open biomass burning (B C BB) transported to Xishuangbanna in 2017. Haze months, between haze and clean months, and clean months in Xishuangbanna were defined according to daily PM 2.5 concentrations of >75, 35–75, and <35 µg/m3, respectively. Results showed that the transport efficiency density (TED) of BC transported to Xishuangbanna was controlled by the prevailing winds in different seasons. The yearly contributions to the effective emission intensity of B C An and B C BB transported to Xishuangbanna were 52% and 48%, respectively. However, when haze occurred in Xishuangbanna, the average B C An and B C BB contributions were 23% and 77%, respectively. This suggests that open biomass burning (BB) becomes the dominant source in haze months. Myanmar, India, and Laos were the dominant source regions of BC transported to Xishuangbanna during haze months, accounting for 59%, 18%, and 13% of the total, respectively. Furthermore, India was identified as the most important source regions of B C An transported to Xishuangbanna in haze months, accounting for 14%. The two countries making the greatest contributions to B C BB transported to Xishuangbanna were Myanmar and Laos in haze months, accounting for 55% and 13%, respectively. BC emissions from Xishuangbanna had minimal effects on the results of the present study. It is suggested that open BB in Myanmar and Laos, and anthropogenic emissions in India were responsible for poor air quality in Xishuangbanna. [Display omitted] [ABSTRACT FROM AUTHOR]

Since 2013, frequent haze pollution events in China have been attracting public attention, generating a demand to identify the haze areas using satellite observations. Many studies of haze recognition algorithms are based on observations from space-borne imagers, such as the Moderate Resolution Imaging Spectroradiometer (MODIS), the Visible Infrared Imaging Radiometer Suite (VIIRS) and the Advanced Himawari Imager (AHI). Since the haze pixels are frequently misidentified as clouds in the official cloud detection products, these algorithms mainly focus on recovering them from clouds. There are just a few studies that provide a more precise distinction between haze and clear pixels. The Medium Resolution Imaging Spectrometer II (MERSI-II), the imager aboard the FY-3D satellite, has similar bands to those of MODIS, hence, it appears to have equivalent application potential. This study proposes a novel MERSI haze mask (MHAM) algorithm to directly categorize haze pixels in addition to cloudy and clear ones. This algorithm is based on the fact that cloudy and clear pixels exhibit opposing visible channel reflectance and infrared channel brightness temperature characteristics, and clear pixels are relative brighter, and as well as this, there is a positive difference between their apparent reflectance values, at 0.865 μm and 1.64 μm, respectively, over bright surfaces. Compared with the Aqua/MODIS and MERSI-II official cloud detection products, these two datasets treat the dense aerosol loadings as certain clouds, possible clouds and possible clear pixels, and they treat distinguished light or moderate haze as possible clouds, possible clear pixels and certainly clear pixels, while the novel algorithm is capable of demonstrating the haze region's boundary in a manner that is more substantially consistent with the true color image. Using the PM2.5 (particle matter with a diameter that is less than 2.5 μm) data monitored by the national air quality monitoring stations as the test source, the results indicated that when the ground-based PM2.5 ≥ 35 μg/cm3 is considered to be haze days, the samples with the recognition rate that is higher than 85% accounted for 72.22% of the total samples. When PM2.5 ≥ 50 μg/cm3 is considered as haze days, 83.33% of the samples had an identification rate that was higher than 85%. A cross-comparison with similar research methods showed that the method proposed in this study had better sensitivity to bright surface clear and haze areas. This study will provide a haze mask for subsequent quantitative inversion of aerosol characteristics, and it will further exert the application benefits of MERSI-II instrument aboard on FY3D satellite. [ABSTRACT FROM AUTHOR]

Land carbon sink is a vital component for the achievement of China's ambitious carbon neutrality goal, but its magnitude is poorly known. Atmospheric observations and inverse models are valuable tools to constrain the China's land carbon sink. Space‐based CO2 measurements from satellites form an emerging data stream for application of such atmospheric inversions. Here, we reviewed the satellite missions that is dedicated to the monitoring of CO2, and the recent progresses on the inversion of China's land carbon sink using satellite CO2 measurements. We summarized the limitations and challenges in current space platforms, retrieval algorithms, and the inverse modeling. It is shown that there are large uncertainties of contemporary satellite‐based estimates of China's land carbon sink. We discussed future opportunities of continuous improvements in three aspects to better constrain China's land carbon sink with space‐based CO2 measurements. [ABSTRACT FROM AUTHOR]

Particulate matter with an aerodynamic diameter of less than 1 μm (PM 1.0) can be extremely hazardous to human health, so it is imperative to accurately estimate the spatial and temporal distribution of PM 1.0 and analyze the impact of related policies on it. In this study, a stacking generalization model was trained based on aerosol optical depth (AOD) data from satellite observations, combined with related data affecting aerosol concentration such as meteorological data and geographic data. Using this model, the PM 1.0 concentration distribution in China during 2016–2019 was estimated, and verified by comparison with ground-based stations. The coefficient of determination (R2) of the model is 0.94, and the root-mean-square error (RMSE) is 8.49 μg/m3, mean absolute error (MAE) is 4.10 μg/m3, proving that the model has a very high performance. Based on the model, this study analyzed the PM 1.0 concentration changes during the heating period (November and December) in the regions where the "coal-to-gas" policy was implemented in China, and found that the proposed "coal-to-gas" policy did reduce the PM 1.0 concentration in the implemented regions. However, the lack of natural gas due to the unreasonable deployment of the policy in the early stage caused the increase of PM 1.0 concentration. This study can provide a reference for the next step of urban air pollution policy development. • Use stacking machine learning algorithm and satellite data to reconstruct PM 1.0. • "Coal-to-gas" policy led to PM 1.0 concentration changes, notably in 2017 and 2019. • Provides valuable insights for mitigate air pollution in Chinese cities. [ABSTRACT FROM AUTHOR]

Abstract: With anionic polymerization, the solution-polymerized styrene-butadiene rubber (SSBR) and solution-polymerized styrene-butadiene rubber with alkoxysilane-functionalization at two ends of macromolecular chains (A-SSBR) were synthesized by dilithium as initiator. The occurrences of end-group functionalization and condensation reaction were confirmed, but also the molecular structure parameters and end-functionalized efficiency of A-SSBR grafted alkoxysilane groups onto the ends of its macromolecular chains were calculated through the characterizations. By this novel structural modification, there were chemical bondings rather than conventional physical adsorption between silica and rubber matrix. This novel technology was beneficial to not only immobilizing the free chain ends to decrease the amount of macromolecular chains' free terminals, but also chemically bonding the rubber chains on the surfaces of silica particles to enhance the filler-polymer interaction significantly. Furthermore, the covering layer of end-functionalized macromolecular chains around the silica particles was conducive to reducing the silica agglomeration and improving the silica dispersion. The structures, morphologies, and properties of SiO2/SSBR and SiO2/A-SSBR composites prepared by co-coagulation and mechanical blending, were investigated. The results showed that SiO2/A-SSBR composites behaved better comprehensive performances including higher wet skid resistance and lower rolling resistance than SiO2/SSBR composites. Consequently, A-SSBR was an ideal material for the green tire treads. [Copyright &y& Elsevier]

The Fourier Transform Spectrometer (FTS) at the Beijing Satellite Meteorological Ground Station observed XCO2 (the dry carbon dioxide column) from 2 March 2016 to 4 December 2018. The validation results of ground-based XCO2, as well as GOSAT, OCO-2, and TanSat XCO2, show that the best temporal matching setting for ground-based XCO2 and satellite XCO2 is ±1 h, and the best spatial matching setting for GOSAT is 0.5° × 0.5°. Consistent with OCO-2, the best spatial matching setting of TanSat is 5° × 5° or 6° × 6°. Among GOSAT, OCO-2, and TanSat, the satellite observation validation characteristics near 5° × 5° from the ground-based station are obviously different from other spatial matching grids, which may be due to the different observation characteristics of satellites near 5° × 5°. To study the influence of local CO2 sources on the characteristics of satellite observation validation, we classified the daily XCO2 observation sequence into concentrated, dispersive, increasing, and decreasing types, respectively, and then validated the satellite observations. The results showed that the concentrated and decreasing sub-datasets have better validation performance. Our results suggest that it is best to use concentrated and decreasing sub-datasets when using the Beijing Satellite Meteorological Ground Station XCO2 for satellite validation. The temporal matching setting should be ±1 h, and the spatial matching setting should consider the satellites observation characteristics of 5° × 5° distance from the ground-based station. [ABSTRACT FROM AUTHOR]

A large number of experimental and theoretical investigations of carbon dioxide (CO) spectra have been conducted since the most recent update of the High-Resolution Transmission Molecular Absorption (HITRAN) database. To maintain optimal parameters, the HITRAN 2004 CO line list has been completely replaced by HITRAN 2008 data in the near-infrared region from 4300 cm to 7000 cm. To examine the effect of this change on the retrieval of CO vertical column data from reflected sunlight spectra in the 1.61-µm spectral window, synthetic measurements for a given atmospheric state and instrument setup were generated and compared using radiative transfer model with the line-transition parameters from the HITRAN 2004 and 2008 databases. Simulated retrievals were then performed based on the optimal estimation retrieval theory. The results show that large systematic errors in atmospheric CO column retrievals were induced by the differences in the HITRAN laboratory line parameters in the 1.61-µm region. The retrieved CO columns were underestimated by >10 ppm using the HITRAN 2004 data, and improvements resulting from the use of the improved HITRAN database were more pronounced at a higher spectral resolution. [ABSTRACT FROM AUTHOR]

Abstract: Daily total suspended particulate (TSP), particle size smaller than 100μm and particle size smaller than 2.5μm (PM2.5) aerosol samples were collected at two sites in Shanghai in four seasons from September 2003 to January 2005. Concentrations of the water-soluble ions (SO4 2−, NO3 −, Cl−, F−, PO4 3−, HCOO−, CH3COO−, NO2 −, MSA, C2O4 2−, NH4 +, Ca2+, Na+, K+, Mg2+) were measured for a total of 202 samples. Daily TSP and PM2.5 mass concentrations ranged from 66.1 to 666.8μgm−3 and 17.8 to 217.9μgm−3, with annual average concentrations of 230.5 and 94.6μgm−3, respectively. The sum of ions contributed an average of 26% and 32% of TSP and PM2.5 mass concentrations, respectively. In PM2.5, the concentration of the major ions followed the order of SO4 2−>NO3 −>NH4 +>Cl−>Ca2+>K+, while in TSP was SO4 2−>NO3 −>Cl−>Ca2+>NH4 +>Na+. These major ions were mainly in the form of (NH4)2SO4, Ca(NO3)2, CaCl2, and CaSO4 in aerosol particles. The aerosol was slightly acidic in the fine particle size range, and alkaline in the coarse mode. Seasonal variation of ion concentrations was significant, with the highest concentrations observed in winter and spring and the lowest in summer and autumn. Three types of air masses, i.e. marine, mixing, and continental, were frequently observed, and their distribution in four seasons might result in the clear seasonal variation. It is Shanghai that has the highest NO3 −/SO4 2− value among all of those cities in China, indicating that as the biggest city in China the mobile source of the air pollution becomes more and more predominant. However, stationary emissions were still the dominant source in Shanghai indicated by the NO3 −/SO4 2− ratio of lower than 1. The formation of NO3 − was largely from the gas-phase photochemical reaction in the cold season, and from the heterogeneous reaction in the warm season, while the formation of SO4 2− might be from the heterogeneous reaction in the entire year round. NH4 +, K+, Cl−, NO3 −, and SO4 2− were mainly influenced by the anthropogenic emissions in land, meanwhile Cl− and SO4 2− might be partly influenced by the sea. Na+, Mg2+, and Ca2+ were derived from both inland crustal and marine sources. Chloride depletion was found especially in summer. The air pollution in Shanghai has proved to be under the influence of both the local emissions and the long-range transport from outside areas. [Copyright &y& Elsevier]

Oceans are widely regarded as major offsets for anthropogenic carbon emissions, leading to an evident lower measured atmospheric CO2 concentration than expected. It is thus of great significance to develop effective means to monitor CO2 fluxes over oceans globally. In this work, we utilized observations obtained by an airborne CO2‐IPDA LIDAR to evaluate the potential of such means in estimating sea‐air CO2 flux. During a flight experiment in 2019, we have estimated the CO2 exchange rate, −1.5 ± 0.18 mmol/m2/h, between the Bohai Bay and the atmosphere using equilibrium atmospheric boundary layer theory. These findings indicated that the forthcoming space‐borne CO2‐IPDA LIDAR is capable of identifying CO2 uptakes over oceans qualitatively, which would be a novel means and a basis for monitoring CO2 fluxes over global oceans. Plain Language Summary: Oceans are regarded as important offsets to anthropogenic CO2 emissions, delaying an increase in atmospheric CO2 concentration. However, there is a lack of understanding of the intensity, distribution, and variability of marine carbon sinks. China is due to launch a space‐borne LIDAR for measuring atmospheric CO2 concentration globally in 2021. In this work, we utilized data collected during a flight test for the forthcoming satellite mission to explore the ability of such a novel means in revealing and estimating CO2 fluxes of oceans quantitatively. Results confirmed an evident CO2 uptake in the Bohai Bay and exhibited a promising prospect for the novel CO2 measuring means. Key Points: We detected XCO2 gradient during a flight campaign in ChinaRetrieve XCO2 in the atmosphere boundary layer by cloud slicing methodProvide a model to retrieve CO2 flux over ocean by CO2‐IPDA system [ABSTRACT FROM AUTHOR]

Using satellite observation data to retrieve atmospheric pollution parameters has become a common technique in the field of remote sensing. Compared with the traditional single-angle and only intensity detection signal loads, multi-angle with/or polarized remote sensing observation instruments provide new ideas for detecting aerosol parameters. Nowadays, multi-angle detection technology and the development of advanced detection loads have become one of the main directions in the field of remote sensing. From the perspective of aerosol characterization from remote sensing measurements, this paper first summarized the information of typical instruments among the development of airborne, space-borne and ground-based detections in various countries. Second, taking the Multi-Angle Imaging SpectraRadiometer (MISR) aboard on Terra, Polarization and Anisotropy of Reflectance for Atmospheric Sciences Coupled with Observations from a LiDAR (PARASOL)/POLDER and Directional Polarized Camera aboard on Gaofen-5 (GF-5/DPC) respectively as representatives of the multi-angle only intensity signal (MAOI, hereafter) and multi-angle polarized signal (MAPS, hereafter), using AERONET/CE-318 as the representative of ground-based remote sensing observations, respectively introduced the current research status of their aerosol characteristics in recent years from three perspectives of data set accuracy evaluation, inversion algorithm improvement and product application. To be specific, 1) the improvements based on MAOI are mainly reflected in the optimization of the aerosol model, and the difficulty lies in how to express the surface contribution by using the empirical orthogonal function. The narrow swath and coarse temporal resolution of MISR determine the rarely popular as MODIS. A higher resolution at 4.4km×4.4 km provide data support for investigating the evolution trends of regional aerosol properties at the regional scale. 2) In addition to establish more approximate aerosol models and acute surface reflectance functions by MAPS, the method of optimal estimation and multi-variate statistical optimal data have been developed to retrieve fine AOD, particle distribution, polarized phase function and etc. Finally, based on the above investigation, it is found that, 1) the planned payloads not only add polarization signal, but also take the importance of multi-spectral into consideration, particularly in near-infrared and short-wave infrared channels, which makes more contributions to improve the retrieval information for coarse particles. 2) The Lookup table-based inversion methods require to refine more appropriate aerosol types and precise surface reflectance relationship, but for the rich information content of hyperspectral load, the inversion efficiency of this method needs to be improved. 3) In addition, the complement of MAOI and MAPS and the fusion of inversion algorithms is also a way to improve the overall inversion accuracy of aerosol characteristics. 4) While improving load performance and enhancing matching inversion algorithms, it is also necessary to vigorously develop calibration techniques for polarized loads, and stable and high-precision calibration coefficients provide the basis for the development of secondary products and the application of tertiary products. 5) domestic MAPS instrument as well as polarization lidar need to be put on the agenda. • The information of typical instruments among the development of airborne, space-borne and ground-based detections in various countries are summarized. • The planned payloads with polarization signal, multi/hyper-spectral are beneficial to coarse particles retrieval. • The fusion of multi-inversion algorithms is also a way to improve the overall inversion accuracy of aerosol characteristics. • Except for improving the retrieval algorithm, it is also necessary to develop calibration techniques for polarized loads. [ABSTRACT FROM AUTHOR]

• Value-added & fully utilization of CWs into building materials. • Addition of PA significantly improved the smoke suppression performance of WPBs. • Increasing of PA contributes to excellent integrated performance of WPBs. • Admirable method promoting the value-added & fully utilization of CWs. • Excellent comprehensive performance promoting WPBs application in green buildings. Construction wastes (CWs) were utilized in this work as the feedstock for manufacturing wasted-based particle boards (WPBs). Results revealed that phytic acid (PA), as a natural and sustainable fire retardant, imparts the WPBs excellent flame retardancy and smoke suppression. The hydrogen bonds network formed among PA, waste particles, and adhesive improves the stress transferring of WPBs when subjected to load, thus elevating the modulus of elasticity and inner bonding strength of PA-treated WPBs. We believe that the as-proposed recycling methods promote the value-added utilization of CWs, and it is also beneficial for realizing the recycling of timber architectures. [ABSTRACT FROM AUTHOR]

Combining DNA damage repair inhibitors and chemotherapeutic agents is an emerging strategy in cancer treatment. In this study, we engineered the polycation nanoparticle (NP), which co-encapsulated DNA damage repair inhibitor Dbait and chemotherapeutic drug Docetaxel (Dtxl), using H1 nanopolymer (folate–-polyethylenimine600–cyclodextrin), and the size of H1/Dbait/Dtxl was about 117 nm. We demonstrated that H1/Dbait/Dtxl enhanced the efficiency of radio-chemotherapy in prostate cancer cells by CCK-8 assay and colony-forming assay. Importantly, the improvement of radio-chemotherapy of H1/Dbait/Dtxl in prostate cancer was also validated in vivo, and the NP did not have a high toxicity profile. The results of immunohistochemistry and western blot supported that the improved therapeutic efficacy was through inhibiting DNA damage repair signalling pathway. Our study supports further investigations using NP to co-deliver DNA damage repair inhibitors and chemotherapeutics to improve the therapeutic efficacy of cancer. [ABSTRACT FROM AUTHOR]