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Graphene shows great potential for flexible optoelectronic devices owing to its unique 2D structure and excellent electronic, optical, and mechanical properties. Chemical vapor deposition (CVD) is the most promising method for fabricating large‐area and high‐quality graphene films at an acceptable cost; therefore enormous efforts have been attempted to investigate the flexible optoelectronic devices based on CVD‐grown graphene. Here, recent advances and significant development of CVD‐grown graphene towards flexible optoelectronics including photodetectors, organic solar cells, and light‐emitting diodes are reviewed. Insight into the challenges of improvement of optoelectronic properties, work function tuning, as well as interfacial control of CVD‐grown graphene for high‐performance devices is provided. In particular, the availability to fabricate large‐area devices on the flexible substrates is discussed, which is crucial to drive the practical use of CVD‐grown graphene for future wearable optoelectronics. [ABSTRACT FROM AUTHOR]

Purpose: Immunohistochemical staining of programmed death-ligand 1 (PD-L1) in tumor biopsies acquired through invasive procedures is routinely employed in clinical practice to identify patients who are most likely to benefit from anti-programmed cell death protein 1 (PD-1) therapy. Nevertheless, PD-L1 expression is observed in various cellular subsets within tumors and their microenvironments, including tumor cells, dendritic cells, and macrophages. The impact of PD-L1 expression across these different cell types on the responsiveness to anti-PD-1 treatment is yet to be fully understood.We synthesized polymer-based lysosome-targeting chimeras (LYTACs) that incorporate both PD-L1-targeting motifs and liver cell-specific asialoglycoprotein receptor (ASGPR) recognition elements. Small-animal positron emission tomography (PET) imaging of PD-L1 expression was also conducted using a PD-L1-specific radiotracer 89Zr-αPD-L1/Fab.The PD-L1 LYTAC platform was capable of specifically degrading PD-L1 expressed on liver cancer cells through the lysosomal degradation pathway via ASGPR without impacting the PD-L1 expression on host cells. When coupled with whole-body PD-L1 PET imaging, our studies revealed that host cell PD-L1, rather than tumor cell PD-L1, is pivotal in the antitumor response to anti-PD-1 therapy in a mouse model of liver cancer.The LYTAC strategy, enhanced by PET imaging, has the potential to surmount the limitations of knockout mouse models and to provide a versatile approach for the selective degradation of target proteins in vivo. This could significantly aid in the investigation of the roles and mechanisms of protein functions associated with specific cell subsets in living subjects.Methods: Immunohistochemical staining of programmed death-ligand 1 (PD-L1) in tumor biopsies acquired through invasive procedures is routinely employed in clinical practice to identify patients who are most likely to benefit from anti-programmed cell death protein 1 (PD-1) therapy. Nevertheless, PD-L1 expression is observed in various cellular subsets within tumors and their microenvironments, including tumor cells, dendritic cells, and macrophages. The impact of PD-L1 expression across these different cell types on the responsiveness to anti-PD-1 treatment is yet to be fully understood.We synthesized polymer-based lysosome-targeting chimeras (LYTACs) that incorporate both PD-L1-targeting motifs and liver cell-specific asialoglycoprotein receptor (ASGPR) recognition elements. Small-animal positron emission tomography (PET) imaging of PD-L1 expression was also conducted using a PD-L1-specific radiotracer 89Zr-αPD-L1/Fab.The PD-L1 LYTAC platform was capable of specifically degrading PD-L1 expressed on liver cancer cells through the lysosomal degradation pathway via ASGPR without impacting the PD-L1 expression on host cells. When coupled with whole-body PD-L1 PET imaging, our studies revealed that host cell PD-L1, rather than tumor cell PD-L1, is pivotal in the antitumor response to anti-PD-1 therapy in a mouse model of liver cancer.The LYTAC strategy, enhanced by PET imaging, has the potential to surmount the limitations of knockout mouse models and to provide a versatile approach for the selective degradation of target proteins in vivo. This could significantly aid in the investigation of the roles and mechanisms of protein functions associated with specific cell subsets in living subjects.Results: Immunohistochemical staining of programmed death-ligand 1 (PD-L1) in tumor biopsies acquired through invasive procedures is routinely employed in clinical practice to identify patients who are most likely to benefit from anti-programmed cell death protein 1 (PD-1) therapy. Nevertheless, PD-L1 expression is observed in various cellular subsets within tumors and their microenvironments, including tumor cells, dendritic cells, and macrophages. The impact of PD-L1 expression across these different cell types on the responsiveness to anti-PD-1 treatment is yet to be fully understood.We synthesized polymer-based lysosome-targeting chimeras (LYTACs) that incorporate both PD-L1-targeting motifs and liver cell-specific asialoglycoprotein receptor (ASGPR) recognition elements. Small-animal positron emission tomography (PET) imaging of PD-L1 expression was also conducted using a PD-L1-specific radiotracer 89Zr-αPD-L1/Fab.The PD-L1 LYTAC platform was capable of specifically degrading PD-L1 expressed on liver cancer cells through the lysosomal degradation pathway via ASGPR without impacting the PD-L1 expression on host cells. When coupled with whole-body PD-L1 PET imaging, our studies revealed that host cell PD-L1, rather than tumor cell PD-L1, is pivotal in the antitumor response to anti-PD-1 therapy in a mouse model of liver cancer.The LYTAC strategy, enhanced by PET imaging, has the potential to surmount the limitations of knockout mouse models and to provide a versatile approach for the selective degradation of target proteins in vivo. This could significantly aid in the investigation of the roles and mechanisms of protein functions associated with specific cell subsets in living subjects.Conclusion: Immunohistochemical staining of programmed death-ligand 1 (PD-L1) in tumor biopsies acquired through invasive procedures is routinely employed in clinical practice to identify patients who are most likely to benefit from anti-programmed cell death protein 1 (PD-1) therapy. Nevertheless, PD-L1 expression is observed in various cellular subsets within tumors and their microenvironments, including tumor cells, dendritic cells, and macrophages. The impact of PD-L1 expression across these different cell types on the responsiveness to anti-PD-1 treatment is yet to be fully understood.We synthesized polymer-based lysosome-targeting chimeras (LYTACs) that incorporate both PD-L1-targeting motifs and liver cell-specific asialoglycoprotein receptor (ASGPR) recognition elements. Small-animal positron emission tomography (PET) imaging of PD-L1 expression was also conducted using a PD-L1-specific radiotracer 89Zr-αPD-L1/Fab.The PD-L1 LYTAC platform was capable of specifically degrading PD-L1 expressed on liver cancer cells through the lysosomal degradation pathway via ASGPR without impacting the PD-L1 expression on host cells. When coupled with whole-body PD-L1 PET imaging, our studies revealed that host cell PD-L1, rather than tumor cell PD-L1, is pivotal in the antitumor response to anti-PD-1 therapy in a mouse model of liver cancer.The LYTAC strategy, enhanced by PET imaging, has the potential to surmount the limitations of knockout mouse models and to provide a versatile approach for the selective degradation of target proteins in vivo. This could significantly aid in the investigation of the roles and mechanisms of protein functions associated with specific cell subsets in living subjects. [ABSTRACT FROM AUTHOR]

Energy efficiency of data centers (DCs) is of great concern due to their large amount of energy consumption and the foreseeable growth in the demand of digital services in the future. The past decade witnessed improvements of the energy efficiency of DCs from an extensive margin—a shift from small to large, more efficient DCs. Improvements from the intensive margin, that is, from more efficient operation, would be critical in limiting the energy consumption and environmental impact of DCs in the upcoming period. Machine learning algorithms have advantages in optimizing the operation of DCs to improve energy efficiency as they have shown the potential of discovering control strategies not found by traditional method, and producing working condition‐dependent control strategies. This study proposes ready‐to‐use machine learning methods with practical details to decrease the most commonly used energy efficiency metric—power usage effectiveness in DCs. We achieved an accurate prediction by properly selecting the features used in the proposed prediction models established by neural network, light gradient boosting machine, recurrent neural network, and random forests. The proposed approaches are implemented in one of the largest hyperscale DCs in China—Tencent Tianjin DC, to optimize the set points of controllable variables in the cooling system and to detect and adjust the unreasonable working conditions in the modular data centers. The lower bound of PUE reduction was 0.005 with the proposed approaches, leading to about 1500 MWh (0.24% of the total designed electricity consumption of this DC) of energy saved per year in this hyperscale DC. The proposed methods have the potential to be transferred to DCs of similar scale, and the framework of our work could serve as a guide for machine learning‐based optimization of environmental indicators in other complex product/service systems. [ABSTRACT FROM AUTHOR]

Large‐area fabrication and stacking of various nanometer‐thick functional layers from solutions is essentially important for the construction of flexible thin‐film optoelectronic devices, but very challenging. The existing fabrication methods suffer from either non‐uniformity caused by the coffee‐ring effect or serious solution waste (excess of 90% for spin coating), and are hard to scale up and create stacks. Here, it is shown that centrifugal casting is a universal, scalable, and efficient method to fabricate uniform nanometer‐thick films and their stacks of various materials. The coffee‐ring effect is effectively suppressed, the solution utilization ratio is higher than ≈61%, and the films/stacks show a smooth surface/high‐quality interface. Using this method, flexible quantum dot light‐emitting diode displays with uniform luminance in a large lighting area of ≈115 cm2 that have not been achieved even on rigid substrates by the existing methods, are realized. This efficient and low‐cost solution processing method paves a way for large‐area fabrication of various flexible thin‐film optoelectronic devices. [ABSTRACT FROM AUTHOR]

An emission inventory, involving both air pollutants (APs) and greenhouse gases (GHGs), is needed so that the questions of air pollution and climate change can be co-addressed, coordinated, and collaborated upon. In this study, an emission inventory, including both APs and CO 2 (representing GHGs), was developed for China 2019 using two special measures. First, the framework of air pollution source classification was used for the integrative inventory and then the CO 2 emissions for each sector/subsector/source in the GHG inventory were precisely arranged into the framework of APs by every possible means such as drawing on the constraints from the International Industrial Classification of All Economic Activities (ISIC), which enabled the sharing of common or intrinsically connected activity data for both APs and CO 2. Second, an attempt was made to deduce the activity data of various industrial processes through proper interpretation of the information carried in Pollutant Permits. The calculated emissions of APs and CO 2 were found to be comparable to the results of other studies. Additionally, the average per capita CO 2 and pollution equivalents (PEs) were 10.29 ± 6.75 tons and 11.72 ± 7.35 tons, respectively, over the provincial regions with per capita gross domestic product (GDP) lower than ￥70000 (about $10000). Whereas the average per capita CO 2 and PEs dropped to 6.10 ± 1.83 tons and 6.70 ± 2.09 tons, respectively, over the provincial regions with per capita GDP higher than ￥70000. This somewhat supports the philosophy of the Environmental Kuznets Curve (EKC) regarding the close connection between emission and development. Moreover, the two emission intensities (for APs and CO 2) were found to vary synchronously among the provinces, reflecting the inter-linked fates of the two emissions under the control measures oriented toward either APs or GHGs. [Display omitted] • An emission inventory integrating air pollutants and CO 2 are compiled. • GHG classification framework are used for the integrative inventory with additional constraints from ISIC. • Pollutant-Permit information is employed to derive activity data of industrial processes and links. • The EKC philosophy on emission/development relation is partly supported. [ABSTRACT FROM AUTHOR]

Graphene has shown tremendous potential as a transparent conductive electrode (TCE) for flexible organic solar cells (OSCs). However, the trade-off between electrical conductance and transparency as well as surface roughness of the graphene TCE with increasing layer number limits power conversion efficiency (PCE) enhancement and its use for large-area OSCs. Here, we use a 300 nm-thick poly[(2,5-bis(2-hexyldecyloxy)phenylene)- alt -(5,6-difluoro-4,7-di(thiophen-2-yl)benzo[ c ]-[1,2,5]thiadiazole)]:[6,6]-phenyl-C 71 -butyric acid methyl ester blend as the photoactive layer and a benzimidazole (BI)-doped graphene as the transparent anode to demonstrate efficient OSCs with good flexibility. It is found that 3 layer (L) graphene had the best balance between sheet resistance, optical transmittance and surface roughness for optimized cell design. A 0.2 cm2 cell with a 3L BI-doped graphene anode had a PCE of 6.85%, which is one of the highest PCE values reported so far for flexible graphene anode-based OSCs. The flexible cells were mechanically robust, showing only a small performance degradation during up to 250 flexing cycles. Moreover, the combination of the thick photoactive layer with the optimized 3L BI-doped graphene TCE enabled production of 1.6 cm2 flexible OSCs with a PCE of 1.8%. Our work illustrates the importance of graphene TCE development for flexible OSCs as well as other wearable optoelectronic devices. Image 1 • Extremely efficient flexible organic solar cells with a doped graphene transparent anode are demonstrated. • 3 layer graphene is determined to be optimal for the cell design. • A 0.2 cm2 cell achieves a high power conversion efficiency of 6.85%. • The thick photoactive layer enables production of a 1.6 cm2-large flexible cell with graphene anode. [ABSTRACT FROM AUTHOR]

N-methyl-2-pyrrolidone (NMP) has been widely used as a solvent for preparing two-dimensional quantum dots (2D-QDs) by probe sonication. Here we found that carbon dots (CDs) are simultaneously produced by the carbonization of NMP when preparing MoS 2 QDs in a NMP solvent by probe sonication. These two kinds of QDs are similar in color, crystal structure, excitation wavelength dependent photoluminescence (PL), and have overlaps in their absorption spectra and coincidence of PL peaks. As a result, the co-production of CDs has not previously been recognized. The CDs show strong optical interactions with the MoS 2 QDs, which leads to a dramatic decrease in the fluorescence intensity of the CDs/MoS 2 QDs. Moreover, we found that the carbonization also occurs for the commonly used organic solvents. These findings suggest that associated production of CDs should be considered when preparing 2D-QDs by probe sonication, and the resulting hybrid CDs/2D-QDs will provide opportunities to design their properties and uses. Image 1 [ABSTRACT FROM AUTHOR]

Keywords: chemical vapor deposition; flexible optoelectronics; graphene; transfer; transparent conductive films EN chemical vapor deposition flexible optoelectronics graphene transfer transparent conductive films 1 1 1 10/21/22 20221017 NES 221017 B Flexible Optoelectronics b In article number 2203115, Wencai Ren and co-workers review the recent advances and significant developments of chemi cal vapor deposition-grown graphene toward flexi ble optoelectronics. Advances in Flexible Optoelectronics Based on Chemical Vapor Deposition-Grown Graphene (Adv. Funct. Chemical vapor deposition, flexible optoelectronics, graphene, transfer, transparent conductive films. [Extracted from the article]

Flexible transparent conductive films (TCFs) are vital to promote the development of flexible and foldable devices including touch panels, displays, organic solar cells, etc. We have prepared a large-area, flexible, and color-neutral single-wall carbon nanotube:sodium dodecylbenzene sulfonate/poly-(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) (SWCNT:SDBS/PEDOT:PSS) composite TCF on a poly(ethylene terephthalate) substrate by a spray coating method. The TCF has a sheet resistance of 178 Ω sq −1 with 85% transmittance at 550 nm. The light transmission characteristics of the films can be tuned by changing the mass fraction of SWCNTs. When the mass fraction of SWCNTs is higher than 4 wt.%, the original blue tint of the TCFs has disappeared. More importantly, we find that SDBS may play a more important role than the SWCNT network in improving the electrical conductivity of the films by acting as a secondary dopant of PEDOT:PSS, which is different from the traditional understanding and existing explanation about the conduction mechanism of PEDOT:PSS-based composite films. [ABSTRACT FROM AUTHOR]

Graphene is a potential nanofiller that can dramatically improve the properties of polymer-based composites at a very low loading. This article reviews the state-of-the-art progress in the fabrication, properties, and uses of polymer composites with different kinds of graphene fillers. The results so far reported in the literature indicate that graphene/polymer composites are promising multifunctional materials with significantly improved tensile strength and elastic modulus, electrical and thermal conductivity, etc. Despite some challenges and the fact that carbon naotube/polymer composites are sometimes better in some particular performance, graphene/polymer composites may have wide potential applications due to their outstanding properties and the availability of graphene in a large quantity at low cost. [ABSTRACT FROM AUTHOR]

Abstract: Multi-walled carbon nanotube (MWCNT)/high density polyethylene (HDPE) and graphene nanosheets (GNS)/HDPE composites with a segregated network structure were prepared by alcohol-assisted dispersion and hot-pressing. Instead of uniform dispersion in polymer matrix, MWCNTs and GNSs distributed along specific paths and formed a segregated conductive network, which results in a low electrical percolation threshold of the composites. The electrical properties of the GNS/HDPE and MWCNT/HDPE composites were comparatively studied, it was found that the percolation threshold of the GNS/HDPE composites (1vol.%) was much higher than that of the MWCNT/HDPE composites (0.15vol.%), and the MWCNT/HDPE composite shows higher electrical conductivity than GNS/HDPE composite at the same filler content. According to the values of critical exponent, t, the two composites may have different electrical conduction mechanisms: MWCNT/HDPE composite represents a three-dimensional conductive system, while the GNS/HDPE composite represents a two-dimensional conductive system. The improving effect of GNSs as conducting fillers on the electrical conductivity of their composites is far lower than theoretically expected. [ABSTRACT FROM AUTHOR]

PM 2.5 pollution has been greatly alleviated in the Beijing-Tianjin-Hebei (BTH) and surrounding area since the implementation of Action Plans for blue skies. Regional air pollution covering multiple cities has recently become common, but an overview from a regional perspective is scarse. In this work, based on PM 2.5 chemical composition data collected in "2 + 26" cities during four consecutive autumn-winter seasons (AWS, from October to next March) from October 2016 to March 2020, we determined the main components driving the increase in PM 2.5 mass concentration within different PM 2.5 concentration regimes. Regionally, in the low PM 2.5 regime (daily concentration ≤ 75 μg/m3), the PM 2.5 mass remained organic matter (OM)-driven during the four AWSs. In the high PM 2.5 regime (daily concentration > 75 μg/m3), regional PM 2.5 increase pattern rapidly transformed from OM-driven during the 2016–2017 AWS to secondary inorganics-driven during the latter three AWSs, with nitrate becoming the dominant component, driving PM 2.5 increase in almost 90% cities in the region. These transitions not only reflect the effectiveness of policies to control emissions from coal combustion and biomass burning in recent years, but also highlight the need to further reduce nitrogen oxides emissions from diesel vehicles, non-road mobile machinery and industry. Besides, the control of sulfur dioxide and primary organic matter should not be neglected, given the substantial contribution of PM 2.5 sulfate under stagnant and humid meteorological conditions, especially in the geographically central and southern parts of the region, and the need for in-depth air quality improvement if the PM 2.5 concentration standards are tightened. Considering the dominance of nitrate in driving regional PM 2.5 pollution, more research on nitrate formation and its atmospheric and climatic impacts is warranted. [Display omitted] • Individual PM 2.5 components behave differently in the low and high PM 2.5 regimes. • Nitrate becomes the dominant component driving PM 2.5 pollution in the high regime. • Organic matter still plays a key role in PM 2.5 mass increase in the low regime. • NO x emission reduction from diesel vehicles and industry is prominent. • POA and SO 2 control is also important, especially in central and southern parts. [ABSTRACT FROM AUTHOR]

Review: 279 refs. [ABSTRACT FROM AUTHOR]

To improve the lipophilicity of ZnO nanopowder in lubricating oil and analyze the surface modification mechanism, stearic acid, oleic acid, and HTAB-SL were selected as surface modifiers. ZnO nanopowders were prepared and modified in a single step by dielectric barrier discharge plasma assisted ball milling for 10 h. The ZnO nanopowder was characterized and analyzed by SEM, FTIR, TG-DSC, x-ray diffractometer, x-ray photoelectron spectroscopy, lipophilicity determination, COF test, etc. The results showed that the size of ZnO nanopowder was 40–100 nm. The results also revealed that the lipophilic groups –CH2 and –CH3 of modifier were successfully modified by ZnO nanopowder. Meanwhile, hydroxyl groups –OH of ZnO nanopowder chemically adsorbed with hydrophilic carboxyl groups –COO– of modifier. The lipophilicity of modified ZnO nanopowder was significantly increased. The COF of oil sample with modified ZnO nanopowder was smaller than that of oil sample with unmodified ZnO nanopowder. The modification mechanism was attributed to the coupling action of plasma, modifier, and mechanical forces of ball milling. The research demonstrated that modified ZnO nanopowder is more suitable as lubricating additive. [ABSTRACT FROM AUTHOR]

Abstract: Patterning is an essential and important process for the future use of single-walled carbon nanotube (SWCNT) thin films (TFs) in electronic devices. Different from traditional Si based electronic materials, SWCNTs can be easily etched when exposed to an oxidative atmosphere. Here we propose a gas exposure method to pattern SWCNT TFs on flexible polymeric substrates, without using vacuum and high temperature treatment. By simply exposing them to ozone for 3min, a high quality SWCNT TF (35–40nm in thickness) pattern is obtained on a poly (ethylene terephthalate) substrate. It is found that the ozone can chemisorb on, functionalize and etch SWCNTs and then destroy the electrically conductive network of SWCNT TFs, which causes a fast resistance increase and achieves efficient SWCNT TF patterns. The proposed patterning method has the advantages of high efficiency, low cost and scale-up ability, and more importantly, it is suitable for assembling flexible electronic devices, indicating prospects for the low-cost and large-scale manufacture of such items. [Copyright &y& Elsevier]

Abstract: We report a simple but highly-effective hydrohalic acid reducing method to reduce graphene oxide (GO) films into highly conductive graphene films without destroying their integrity and flexibility at low temperature based on the nucleophilic substitution reaction. GO films reduced for 1h at 100°C in 55% hydroiodic (HI) acid have an electrical conductivity as high as 298S/cm and a C/O ratio above 12, both of which are much higher than films reduced by other chemical methods. The reduction maintains good integrity and flexibility, and even improves the strength and ductility, of the original GO films. Based on this reducing method, a flexible graphene-based transparent conductive film with a sheet resistance of 1.6kΩ/sq and 85% transparency was obtained, further verifying the advantage of HI acid reduction. [ABSTRACT FROM AUTHOR]

Abstract: A weak interaction between carbon nanotubes (CNTs) and polymers was found to reduce polymer-wrapping on CNT surface, decrease the contact resistance between CNTs, and increase the electrical conductivity of their composites. Thermodynamic properties such as surface energy of components, filler–polymer interactions, and wettability of carbon/polymer systems were analyzed. It was found that the graphitized CNTs filled polyoxymethylene (POM) system exhibits the weakest CNT–polymer interaction among all the investigated systems and a poor wettability. Consequently, the graphitized CNT/POM composites possess a high electrical conductivity and a low percolation threshold of 0.5wt.% CNT loading, which is associated with the weak CNT–polymer interaction, low contact resistance between CNTs, good connectivity of CNT networks, and high crystallinity of POM in the composites. The results obtained imply that high-performance composites with optimal CNT-network structures can be designed and fabricated by fully considering the surface properties of components and CNT–polymer interactions. [Copyright &y& Elsevier]

In human body, alveoli are the primary sites for gas exchange which are formed by the dilation and protrusion of bronchioles at the end of the lung, and the rapid gas‐exchanging process in the alveoli ensures normal life activities. Based on the unique structures and functions of alveoli, it is necessary to study the regulation mechanism of its formation, respiration, and apoptosis. Herein, a class of reversible addition−fragmentation chain transfer (RAFT)‐derived amphiphilic triblock copolymers, PEO‐b‐P(DEAEMA‐co‐FMA)‐b‐PS is designed and synthesized. Due to the amphiphilic and gas‐responsive segments, these triblock copolymers can self‐assemble in aqueous solution and undergo the morphological transition from nanotubes to vesicles under gas stimulation; meanwhile, in the cycles of CO2/O2 stimulation, these vesicles can further realize the volume expansion and contraction, eventually rupture. The gas‐driven morphological transformations of these aggregates successfully imitate the formation, respiration, and apoptosis of alveoli, and provide an essential basis for revealing the life phenomena. [ABSTRACT FROM AUTHOR]

Plant phenological events are sensitive indicators of climate change, and their change could markedly affect the structure and function of ecosystems. Previous studies have revealed the spatiotemporal variations in the phenological events of woody plants. However, limited studies have focused on the phenophases of herbaceous plants. In this study, by using a meta-analysis method, we extracted information about the phenological changes in herbaceous plants in China's grasslands from existing studies (including the period, station, species, phenophases, phenological trends, and climatic determinants) and analyzed the patterns manifested in the dataset. The results showed that the spring phenophases (e.g., first leaf date and first flowering date) of the herbaceous plants mainly advanced over the past 30 years, but a large difference existed across grassland types. The spring phenophases of forages (species from the Cyperaceae, Gramineae, and Leguminosae families) became earlier in the desert steppe and alpine steppe but showed no apparent trends in the alpine meadow and even became later in the meadow steppe and typical steppe. In most cases, the increase in spring temperatures and precipitation promoted the greening up of herbaceous plants, while sunshine duration was positively correlated with the green-up date of herbaceous plants. For the autumn phenophases, the proportions of the earlier and later trends were very close, but the trends varied among the grassland types. The leaf coloring dates of the forages were delayed in the meadow steppe and alpine steppe but showed no distinct pattern in the typical steppe or alpine meadow and even became earlier in the desert steppe. In most cases, the increase in growing season temperature led to an earlier leaf coloring date of the herbaceous plants, but the increase in the preseason precipitation delayed the leaf coloring date. Our results suggested that the phenophases of herbaceous plants have complicated responses to multiple environmental factors, which makes predicting future phenological changes difficult. [ABSTRACT FROM AUTHOR]

Water electrolysis in alkaline electrolyte is a promising technology for large-scale hydrogen production. However, the hydrogen evolution reaction (HER) is quite sluggish in alkaline electrolyte. Developing highly active and stable non-noble metal electrocatalysts is highly desired to solve this issue but of great challenge. Here, we report a catalyst constructed by Ni–Mo–N nanoparticles decorated on nitrogen-doped reduced graphene oxide (Ni–Mo–N/NG). Due to the high intrinsic electrocatalytic activity of heterostructured Ni–Mo–N nanoparticles and synergistic effects between the nanoparticles and graphene, the catalyst exhibits excellent HER electrocatalytic activity with zero onset potential and 46.6 and 159.8 mV overpotentials for 10 and 100 mA cm−2, respectively, in alkaline electrolyte at low mass loading. Such electrocatalytic performances exceed those of many reported non-noble metal catalysts even with much higher mass loading, demonstrating the great potential of our Ni–Mo–N/NG catalysts for hydrogen production by water electrolysis. Image 1 [ABSTRACT FROM AUTHOR]

Coking industry is an important volatile organic compounds (VOCs) emission source in China, however, detailed information on VOCs emissions is lacking. Therefore, we selected a typical mechanized coking plant and collected air samples according to the Emission Standard of Pollutants for Coking Chemical Industry (GB16171-2012). Using gas chromatography-mass spectrometry method, we analyzed the VOCs in the air samples, and applied maximum increment reactivity (MIR) rule to estimate ozone formation potential (OFP) of the VOCs emitted from the coke production. More than 90 VOCs species were detected from the coking plant, including alkanes, alkenes, alkynes, aromatic hydrocarbons, halogenated hydrocarbons and oxygenated VOCs. The concentrations of VOCs (ρ(VOCs)) generated at different stages of the coking process are significantly different. ρ(VOCs) from coke oven chimney had the highest concentration (87.1 mg/m3), followed by coke pushing (4.0 mg/m3), coal charging (3.3 mg/m3) and coke oven tops (1.1 mg/m3). VOCs species emitted from the coke production processes were dominated by alkanes and alkenes, but the composition proportions were different at the different stages. Alkenes were the most abundant emission species in flue gases of the coke oven chimney accounting for up to 66% of the total VOCs, while the VOCs emissions from coke pushing and coal charging were dominated by alkanes (36% and 42%, respectively), and the alkanes and alkenes emitted from coke oven top were similar (31% and 29%, respectively). Based on above results, reduction of VOCs emissions from coke oven chimney flue gases is suggested to be an effective measure, especially for alkenes. Image, graphical abstract [ABSTRACT FROM AUTHOR]

• The corrosion and wear behaviors of cylinder liner in marine diesel engine under different simulated conditions were investigated. • FeSO 4 , Fe 3 O 4 , Fe 2 O 3 , FeO and FeS were the products of chemical corrosion and electrochemical corrosion of cylinder liner in marine diesel engine burning low sulfur fuel oil. • The interaction between corrosion and wear of cylinder liner in marine diesel engine burning low sulfur fuel oi were studied. • There was an obvious interaction between corrosion and wear, corrosion and wear promoted each other and jointly accelerated the loss of cylinder liner in marine diesel engine burning low sulfur fuel oil. The use of low sulfur fuel oil causes the abnormal corrosion and wear of cylinder liner in marine diesel engine. Marine diesel engine cylinder liner material and marine diesel engine cylinder oil were taken as test material and test oil, respectively. Static immersion test, electrochemical test and corrosion wear tests were carried out by simulating the different working conditions of marine diesel engine. To analyze the corrosion behaviors of cylinder liner in marine diesel engine, its corrosion mass loss, polarization curve, electrochemical impedance plots, surface morphology and composition distribution were examined. Also, the electrochemical corrosion volume loss and friction volume loss were analyzed quantitatively to reveal the mechanism of interaction between corrosion and friction. The results showed that the severity of corrosion caused to cylinder liner varied under different working conditions of marine diesel engine, with the water, oxygen and acid in cylinder oil as the main causes for the corrosion of cylinder liner. There was an interaction occurring between the corrosion and wear of cylinder liner in marine diesel engine, and the interaction volume loss ΔV between the corrosion and wear to the total wear volume loss V T (ΔV/V T) was 13.9%. The promotion volume loss rate of wear on corrosion V mc was about 3.86% of the total volume loss V T (V mc /V T). The promotion volume loss rate of corrosion on wear V cm was about 10.02% of the total volume loss V T (V cm /V T). The interaction between the corrosion and wear was an important factor affecting the wear resistance and corrosion resistance of marine diesel engine cylinder liner. This study provides theoretical reference for suppressing the corrosion and wear behaviors of cylinder liner in the marine diesel engine burning low sulfur fuel oil. [ABSTRACT FROM AUTHOR]

In order to improve the regional air quality, many control strategies have been developed by Chinese government for reducing air pollutant emission from power plants, industrial and transport sources during the past decade. However, little attention has been paid to residential combustion sources. To fill the knowledge gap, a series of surveys were carried out to investigate the residential energy use in Beijing-Tianjin-Hebei (BTH) region during the period of 2013–2014. Study shows that the actual average amount of residential coal consumption is over 0.7 t yr − 1 per capita in 2013, which is much higher than that of 0.15 t yr − 1 per capita reported in the 2014 China Energy Statistical Yearbook (CESY). Combining the investigated activities data with the best available emission factors (EFs), bottom-up method was used to evaluate the potential air pollutant emissions from residential coal combustion in BTH region in 2013. The results indicate that Baoding is the top contributor to the whole BTH region and accounts for approximately 15% of the regional residential emissions in 2013. The spatial pattern of air pollutants shows that high emissions locate in the southeast, along the Yanshan and Taihang Mountains, where much more rural people live and coal combustion is prevalent in winter. The future emission scenario at the end of the 13th Five Year Plan (in 2020) was also predicted based on the policy guidance for the residential coal consumptions in the BTH region. The scenario analysis indicates that air pollutant emissions will drop substantially around 90% because more strict rules will be made for reducing the residential coal consumption. With combined survey information and statistical data, the uncertainty of the emission inventory which was established in this study for the residential sector in the BTH region is reduced and the emission inventory is more reliable for air quality decision making. [ABSTRACT FROM AUTHOR]

City clusters play an important role in air pollutant and greenhouse gas (GHG) emissions reduction in China, primarily due to their high fossil energy consumption levels. The "2 + 26" Cities, i.e., Beijing, Tianjin and 26 other perfectures in northern China, has experienced serious air pollution in recent years. We employ the Greenhouse Gas and Air Pollution Interactions and Synergies model adapted to the "2 + 26" Cities (GAINS-JJJ) to evaluate the impacts of structural adjustments in four major sectors, industry, energy, transport and land use, under the Three-Year Action Plan for Blue Skies (Three-Year Action Plan) on the emissions of both the major air pollutants and CO 2 in the "2 + 26" Cities. The results indicate that the Three-Year Action Plan applied in the "2 + 26" Cities reduces the total emissions of primary fine particulate matter with an aerodynamic diameter of ≤ 2.5 μm (PM 2.5), SO 2 , NO x , NH 3 and CO 2 by 17%, 25%, 21%, 3% and 1%, respectively, from 2017 to 2020. The emission reduction potentials vary widely across the 28 prefectures, which may be attributed to the differences in energy structure, industrial composition, and policy enforcement rate. Among the four sectors, adjustment of industrial structure attains the highest co-benefits of CO 2 reduction and air pollution control due to its high CO 2 reduction potential, while structural adjustments in energy and transport attain much lower co-benefits, despite their relatively high air pollutant emissions reductions, primarily resulting from an increase in the coal-electric load and associated carbon emissions caused by electric reform policies.. • Impacts of structural adjustments on emissions of air pollutants and CO 2 in the "2 + 26" Cities are evaluated. • The higher the pollutant emissions are, the higher the reduction potential. • Adjustment of industrial structure attains the highest co-benefits of CO 2 reduction and air pollution control. [ABSTRACT FROM AUTHOR]

Protected areas (PAs) have been established worldwide to conserve biodiversity. However, the conservation effectiveness of different PA functional zones remains poorly understood. Here, we investigated National Nature Reserves (NNRs) in China to explore and quantify the conservation in their core, buffer, and experimental zones. We compared the area and proportion of forest loss for these functional zones during the period from 2001 to 2018. The results showed that the forest loss in NNRs showed a decreasing trend since 2011, indicating that NNRs reduced the forest loss. There was no significant difference of forest loss proportion (p = 0.42) between the core zones (0.60 ± 1.32%) and buffer zones (0.55 ± 0.88%), implying that their performance in forest conservation was similar. There was a significant difference between experimental and core zones as well as between experimental and buffer zones both in forest loss area and proportion (p ˂ 0.05). We confirmed that the proportion of functional zones significantly affects the conservation effectiveness, i.e., an improper proportion of core zones or buffer zones may lead to forest loss. Therefore, we suggest an optimal proportion of core and buffer zones at 30%–50% and 10%–40%, respectively. Overall, the effectiveness of functional zones in forest nature reserves was assessed on a national scale. The results of this study support the recent adjustment in the PA functional zoning system in China. • National Nature Reserves in China have reduced the forest loss trend. • Buffer zones performance is similar to that of core zones for forest conservation. • Buffer and core zones are more effective than experimental zones for conservation. • Proportion of functional zones significantly affects conservation effectiveness. [ABSTRACT FROM AUTHOR]

Abstract: The present study evaluated the herbicidal potential of extracts from chicory (Cichorium intybus L.) roots on the germination of Echinochloa crusgalli L. Beauv and Amaranthus retroflexus L. Eight ultrasonic assisted-extraction (UAE) conditions were optimized, using an orthogonal matrix design. The extract concentrations that would yield the largest allelopathic effects on the plant species were estimated by a modeling analysis. Our results showed that an alcohol solvent extract of chicory root had significant herbicidal activity which depended on the extract concentrations and the target species. The half-inhibitory concentrations of crude extract of chicory root ranged from 0.5gl−1 to 40.5gl−1. At a frequency of 40kHz, the optimum UAE conditions to produce an extract for use as herbicide against E. crusgalli L. included an ethanol content (Ec) of 50% (v/v), a solvent-to-solid ratio (SR) of 16:1, an ultrasound temperature (UT) of 35°C, an impregnation time (Imt) of 24h with two rounds of impregnation (Imr), a sonication period (St) of 120min with two rounds of sonication (Sr) and an ultrasound input power (P) of 200W. The optimum conditions to produce an extract for use against A. retroflexus L. included an Ec of 100% (v/v), a SR of 16:1, an UT of 20°C, an Imt of 48h with two Imr, a St of 30min with one Sr and a P of 400W. The extract had the largest inhibitory effects on the germination index and root growth of both E. crusgalli L. and A. retroflexus L. at concentrations ranging from 30.8 to 33.7gl−1. At a concentration of 4.2gl−1, the extract significantly enhanced the shoot growth of A. retroflexus L. Overall, chicory root extract has potential for use as a main ingredient in natural herbicides or for development as a novel plant-derived herbicide. [Copyright &y& Elsevier]

Protected areas (PAs) are considered essential for biodiversity conservation, and concerns about the effectiveness of PAs in terms of reducing deforestation are growing. However, few studies have identified the management measures that best reduce deforestation within existing PAs. Here, we carried out 10-year (from 2007 to 2016) field surveys and obtained a database of 10 management measures of 227 PAs mainly protecting forest ecosystems in China. We examined the contributions of the above 10 management measures in relation to the effectiveness of 227 PAs in reducing deforestation. Our results indicated that 52.68% of PAs had positive effects related to reducing deforestation (E > 0, P < 0.05), while 16.52% of PAs had negative effects (E < 0 , P < 0.05). The most important management measures affecting the effectiveness of PAs in reducing deforestation were funding, infrastructure, and scientific research and monitoring. Thus, our study provides evidence indicating that improved funding and scientific research benefit the effectiveness of PAs. The findings have global implications for guiding PAs to take explicit measures to improve the outcomes of biodiversity conservation. Unlabelled Image • Ten-year field surveys for PAs were conducted to assess their management measures. • The effectiveness of PAs was assessed by PSM approach. • The contributions of 10 management measures to effectiveness of PAs were examined. • More than half of the PAs positively reduced deforestation. • Improved funding and scientific research benefit the effectiveness of PAs. [ABSTRACT FROM AUTHOR]

Catering oil fumes are a major hazard to human health. In particular, the typical Chinese cooking style is characterised by a high temperature frying process that produces high levels of cooking oil fumes. However, limited data relating to this sector mean that national emission inventory data specific to the catering service industry do not exist. To address above deficiency and thus to establish the inventory of a city, or a province, or even a country, a door-to-door survey campaign was launched in the Chinese cities of Heze and Linfen to determine the structure of local catering industries. Data revealed that the number of catering businesses per 104 people was 17 ± 4. Of these, 3.0 ± 1.4, 15.0 ± 1.4, and 82.0 ± 0.0% were classified as large, medium, and small enterprises, respectively. Furthermore, the installation rates of fume purifiers were 74 ± 13, 66 ± 9, and 51 ± 14% for large, medium, and small enterprises, respectively, with net removal efficiencies of 63 ± 11, 50 ± 7, and 31 ± 8%, respectively. This information was extrapolated across all provincial regions of China to construct a provincial and national emission inventory. In 2017, China's national catering industry released approximately 34 kt of volatile organic compounds (VOCs), 38 kt of particulate matter with a diameter less than 2.5 μm (PM 2.5), 48 kt of particulate matter with a diameter less than 10 μm (PM 10), 1 kt of black carbon (BC), and 27 kt of organic carbon (OC). A significant correlation was observed between vegetable oil consumption and emissions (e.g., for VOCs, y = 14.94 x + 76.50, R2 = 0.87, where y is VOCs emissions and x is vegetable oil consumption), indirectly corroborating the rationality of the inventory. Moreover, this correlation provides the potential for a dynamic inventory based on vegetable oil consumption. Future studies are proposed to address more influential factors to improve the reliability of the national inventory and refer to big data, rather than door-to-door investigation, to identify the amount of catering service businesses in a region. Unlabelled Image • Intensive surveys on catering industry information performed in two Chinese cities • Survey data help establish a national emission inventory of catering industry. • A significant correlation observed between vegetable oil consumption and emissions. • This correlation indirectly verifies by the rationality of the inventory. • This relation useful for dynamically updating emission inventory of catering sector [ABSTRACT FROM AUTHOR]

Coal-dominated winter heating practices in China are largely accepted to be a leading cause of winter haze in the region though the amount of coal for heating is actually much lower than for power generation or industrial process. However, little is known about how the total rural coal weight in a region could be attributed to real time (e.g., daily) patterns, limiting the understanding of dynamic impacts of coal emissions and the adoption of timely measures against predicted haze. Considering that winter heating essentially protects against cold temperatures, coal burning strength may be related to the temperatures that people experience. A field study was organized to test the validity of this hypothesis. A system was designed to continuously monitor every instance of coal addition, and coal consumption on any given day for a whole village (W DAY) was calculated by summating all the additions. Meanwhile, a new term, composite temperature (T COM), which incorporates a few weather-related elements, was introduced to represent cold temperatures that individuals experience. It was found that W DAY and T COM presented opposite variations, and a negative linear correlation was observed (W DAY = −0.75 T COM + 11.86, R 2 = 0.75), revealing the feasibility of estimating coal consumption on a certain day (W DAY) based on weather data (T COM) for a given village. An extensive form of the algorithm for any area of interest (e.g., a district, city, or province) can be expressed as W DAY = (−0.75 T COM + 11.86)‧ N H /834, where N H denotes the number of households in a region. This algorithm reflects the essence of winter heating (to resist cold temperatures), and therefore its logic is highly likely to be useful for any countries of the world regardless of what forms of energy used (coal or other energy forms) provided the energy involved is unexceptionally used for winter heating, though there may be some uncertainties in estimated coal consumption due to multiple factors. Unlabelled Image • Coal consumption and weather condition simultaneously monitored in a heating season • An algorithm for calculating daily coal consumption (emission) based on temperature • The algorithm enables real time simulation of heating coal impact on air quality. • The inside logic may find application in any countries with winter heating practice. [ABSTRACT FROM AUTHOR]

• Trend analysis, driving force identification and risk prediction were carried out. • Random Forest Regression was applied to identify driving force. • Climatic variables appeared to be important drivers of vegetation coverage dynamics. • The reliability and efficiency of risk assessment were enhanced by Bayesian Belief Network. • Current enclosed rangelands poorly represented the area with the highest risk. Rangeland degradation in China has significant impacts both on the ecosystem and on the pastoralists' life. However, the emphasis of current management practice is always put on the rangeland with serious degradation problem. How to effectively avoid the degradation risks is still unclear. Thus, an integrated approach for rangeland degradation risk assessment was designed, consisting of the analysis of vegetation dynamics, driving forces identification and degradation risk prediction. Firstly, Vegetation Indexes and field survey data were applied to build regression model to calculate the vegetation coverage status and trend of change in each grid. Secondly, the important driving forces of rangeland dynamics were identified based on the local knowledge and objective data. Thirdly, Bayesian Belief Network (BBN) was trained in each seasonal rangeland to predict the probability of rangeland degradation in each grid. Rangeland degradation in Burqin County, Xinjiang, China was served as a case to test the practicability of this approach. The results indicated that during 2000 and 2013 most of the rangeland grids remained stable. Twelve factors were identified to be the driving force of the trend of vegetation coverage dynamics. BBNs showed that in most of the study area degradation risk was less than 50%, and the grids facing the maximum risk were only appeared in a small range. According to the case study, the integrated approach based on Random Forest and BBN model was turned out to be a practical and effective tool for the risk assessment of rangeland degradation. [ABSTRACT FROM AUTHOR]