SMRT and Illumina RNA-Seq Identifies Potential Candidate Genes Related to the Double Flower Phenotype and Unveils SsAP2 as a Key Regulator of the Double-Flower Trait in Sagittaria sagittifolia.

Double flowers are one of the important objectives of ornamental plant breeding. Sagittaria sagittifolia is an aquatic herb in the Alismataceae family that is widely used as an ornamental plant in gardens. However, the reference genome has not been published, and the molecular regulatory mechanism of flower formation remains unclear. In this study, single molecule real-time (SMRT) sequencing technology combined with Illumina RNA-Seq was used to perform a more comprehensive analysis of S. sagittifolia for the first time. We obtained high-quality full-length transcripts, including 53,422 complete open reading frames, and identified 5980 transcription factors that belonged to 67 families, with many MADS-box genes involved in flower formation being obtained. The transcription factors regulated by plant hormone signals played an important role in the development of double flowers. We also identified an AP2 orthologous gene, SsAP2, with a deletion of the binding site for miR172, that overexpressed SsAP2 in S. sagittifolia and exhibited a delayed flowering time and an increased number of petals. This study is the first report of a full-length transcriptome of S. sagittifolia. These reference transcripts will be valuable resources for the analysis of gene structures and sequences, which provide a theoretical basis for the molecular regulatory mechanism governing the formation of double flowers.

Physico-chemical characterization and source tracking of black carbon at a suburban site in Beijing.

Particles from ambient air and combustion sources including vehicle emission, coal combustion and biomass burning were collected and chemically pretreated with the purpose of obtaining isolated BC (black carbon) samples. TEM (transmission electron microscopy) results indicate that BC from combustion sources shows various patterns, and airborne BC appears spherical and about 50 nm in diameter with a homogeneous surface and turbostratic structure. The BET (Barrett-Emmett-Teller) results suggest that the surface areas of these BC particles fall in the range of 3-23 m2/g, with a total pore volume of 0.03-0.05 cm3/g and a mean pore diameter of 7-53 nm. The nitrogen adsorption-desorption isotherms are indicative of the accumulation mode and uniform pore size. O2-TPO (temperature programmed oxidation) profiles suggest that the airborne BC oxidation could be classified as the oxidation of amorphous carbon, which falls in the range of 406-490°C with peaks at 418, 423 and 475°C, respectively. Generally, the BC characteristics and source analysis suggest that airborne BC most likely comes from diesel vehicle emission at this site.

Emission factors and emission inventory of volatile organic compounds (VOCs) from hair products application in hair salons in Beijing through measurement.

Hair products application in hair salons is a potential VOCs emission source. 139 representative hair salons were investigated and 88 hair products were sampled to establish VOC emission factors and emission inventory. VOC emission factors were 6.75 g/kg for shampoo, 43.55 g/kg for hair mask, 27.62 g/kg for hair oil, 52.44 g/kg for hair dye, 32.01 g/kg for perm cream, 54.08 g/kg for elastin, 156.40 g/kg for hair styling gel, 78.88 g/kg for hair clay, 70.25 g/kg for hair wax, and 447.88 g/kg for hair styling spray. VOC emissions from hair products application in hair salons in Beijing had increased from 362.77 t in 2011 to 393.40 t in 2020. Hair styling spray, hair dye, perm cream and hair mask were the four largest contributors to total emissions, together accounting for 93.68 %. The high VOC emissions and emission intensity mainly located in six central urban districts. The per capita VOC emissions were 0.018 kg VOCs/person/year in 2020. Projection indicates it can reduce VOC emissions by 9.72 % by 2030 compared with that in 2020 if the VOC content limit standard of hair products will be implemented, otherwise, VOC emissions keep raising, urgently needing VOC control measures in hair products application.

Emission factors and characteristics of volatile organic compounds (VOCs) from adhesive application in indoor decoration in China.

Adhesive application in indoor decoration is an important anthropogenic volatile organic compound (VOC) emission source of both indoors and outdoors. However, few studies have been conducted on VOC emission factors and characteristics from indoor decorating adhesives. In this study, the VOC emission factors were obtained by measurement of VOCs in 210 adhesives. The results showed that the VOC emission factors were 41.23 g/L for wall and ground solidify, 33.49 g/L for tile adhesive, 76.88 g/L for white glue, 52.36 g/L for wallcovering adhesive, 132.28 g/L for sealant glue, 49.33 g/kg for foaming adhesive, 654.23 g/L for all-purpose adhesive, 251.93 g/L for free nails adhesive, 152.01 g/L for marble glue, and 136.79 g/L for beautiful sealant. Methodology for calculating activity data of decorating adhesive consumptions was developed and a VOC emission inventory from adhesive application in indoor decoration was developed using a bottom-up estimation methodology. The VOC emissions from 2012 to 2017 in China were 235,987.76, 246,230.47, 250,981.62, 249,849.48, 227,150.33 and 212, 433.07 t, respectively. The beautiful sealant, wall and ground solidify, sealant glue and all-purpose adhesive contributed the most of the total emissions, collectively accounting for 78.14%. Shandong, Jiangsu, Zhejiang, Sichuan and Guangdong ranked as the top five provinces for VOC emissions, together contributing 39.10% to the national total emissions. Shandong and Jiangsu reached up to 17,057.95 t/year and 15,207.92 t/year, respectively. Priority should be given to four types of adhesives with pretty high VOC contents for designing effective VOC control measures, including solvent-based all-purpose adhesive, solvent-based free nails adhesive, solvent-based sealant glue, and solvent-based beautiful sealant. Future emission trends are projected through 2030 based on current emission control policies and real estate trend. It may be possible to reduce VOC emissions by 60.81% and 69.37% by 2030 under the two scenarios, respectively, compared with the VOC emissions in 2017.

Source profiles and emission factors of VOCs from solvent-based architectural coatings and their contributions to ozone and secondary organic aerosol formation in China.

Volatile organic compounds (VOCs) from solvent-based architectural coatings (SBACs) play an important role in photochemical air pollution with increasing consumption of architectural coatings in China. In this study, we collected 148 typical SBACs of 3 types in China. The TVOC emission factors and source profiles were established, the contributions of SBACs to ozone and secondary organic aerosol (SOA) formation were investigated. The VOC emissions and O3 and SOA amounts formed in chemical reactions from SBACs in 2017 were estimated. Key organic groups and VOC species with high reactivity were identified. According to the results, the TVOC emission factors were 507.17 g L-1 for solvent-based anticorrosive coatings, 381.34 g L-1 for solvent-based floor coatings and 459.68 g L-1 for solvent-based fire-retardant coatings. The VOC emissions were 186,902.11 t, 88,225.41 t and 71,352.32 t; the O3 amounts formed were 742,001.39 t, 397,896.60 t and 244,738.46 t; the SOA amounts formed were 3934.29 t, 2488.04 t and 1104.61 t, respectively, from 3 types of SBACs in 2017. The O3 production factors were 1781.82 g O3 (kg paint)-1, 1457.50 g O3 (kg paint)-1 and 1176.63 g O3 (kg paint)-1, the SOA production factors were 9.45 g SOA (kg paint)-1, 9.11 g SOA (kg paint)-1 and 5.31 g SOA (kg paint)-1, for 3 types of SBACs. Priority should be given to organic group of aromatics and top 17 VOC species with high reactivity for O3 and SOA eliminating strategies, especially three xylenes (o-xylene, m-xylene and p-xylene), ethylbenzene, trimethyl benzenes (1,3,5-trimethyl benzene, 1,2,3-Trimethyl benzene) and toluene.

[Establishment of VOCs Emissions Factor and Emissions Inventory from Using of Architectural Coatings in China].

Volatile organic compounds (VOCs)are important air pollutants in China, and control of their emission is an important subject of air pollution prevention and control.Architectural coatings play a significant role as sources of atmospheric VOCs in China.Due to recent economic development and increase in the levels of urbanization, the building of residences and other buildings is ongoing all the time, which results in increasing demand for architectural coatings and the VOCs pollution caused by painting operations.However, there are few studies of the VOCs emission factors and VOCs emissions due to architectural coatings.In this paper, a set of bottom-up VOCs emission inventory estimation methods for architectural coatings in China was established.The architectural coatings VOCs emission factors were gotten by actual measurement of VOCs in architectural coatings and by summarizing studies of VOCs contents in architectural coatings.Combining these results with the consumption of architectural coating sources, a VOCs emission inventory of architectural coatings in China from 2013 to 2016 was established.The results showed the following.① VOCs emission factors were 24.63 g·kg-1 for water-based interior wall coatings; 17.5 g·kg-1 and 298.8 g·kg-1 for water-based and solvent-based exterior wall coatings, respectively. They were 2.75, 87.86, and 400 g·kg-1 for water-based, reaction-type, and solvent-based waterproof coatings, respectively. For water-based, solventless, and solvent-based floor coatings, they were 86.2, 25.24, and 317 g·kg-1, respectively; and 31.95 g·kg-1 and 464.61 g·kg-1 for water-based and solvent-based anticorrosive coatings respectively. The emission factors were 59.7 g·kg-1 and 347.2 g·kg-1 for water-based and solvent-based fire retardant coatings, respectively. ② VOCs emissions from the use of architectural coatings were 255900 t, 287500 t, 319700 t, and 348000 t from 2013 to 2016 in China, with an upward trend. ③ Total VOCs emissions from architectural coatings was 348000 t in 2016, and the VOCs emissions from floor coatings was 78700 t, accounting for 22.61% with the maximum contribution rate. The VOCs emissions from exterior wall coatings were 64900 t, accounting for 18.65% (second place), and the VOCs emissions from fire retardant coatings and anticorrosive coatings (functional coatings) were 64500 t and 50800 t, accounting for 18.53% and 14.6% respectively. The VOCs emissions from waterproof coatings and interior wall coatings were 46100 t and 43000 t, accounting for 13.25% and 12.36%, respectively. ④ The consumption of water-based architectural coatings reached a total of 4889400 t in 2016 with VOCs emissions of 97900 t and average VOCs emissions factor of 20.02 g·kg-1; however, the consumption of solvent-based architectural coatings totaled 636500 t with VOCs emissions of 227200 t and average VOCs emission factor of 356.95 g·kg-1. Reducing the consumption of solvent-based coatings would be favorable for reduction of VOCs emissions. ⑤ As for the spatial distribution, architectural coating-related VOCs emissions were mainly concentrated in Shandong, Jiangsu, Zhejiang, Henan, Sichuan, Guangdong, and Hebei provinces, which have large populations. The province with the highest VOCs emissions was Shandong, with a percentage of 9.36%, and the second was Jiangsu, with a percentage of 8.54%.

[Research and Application of the Technical Method for the Compilation of VOCs Emission Inventories from Architectural Coatings in Beijing].

VOCs(volatile organic compounds) are important precursors of ozone and secondary organic aerosols in the atmosphere, which increase atmospheric oxidation, creating pollutants such as photochemical smog, fine particulate matter and so on. This study documented information about architectural coating VOC emission characteristics to facilitate formulation of control strategies by environmental management departments. This research was based on measured data for architectural wall and waterproof coatings to identify localized emission factors, used industry research to compile additional information, and was combined with the Beijing completed building inventory, to develop a compilation method for VOC emissions from architectural coatings. According to the above research to estimate VOC emissions of the interior wall, exterior wall and waterproof coatings in 2015, analysis of the spatial distribution of VOCs was performed and VOC emissions were estimated under two conditions regarding whether to limit the content of hazardous substances in architectural coatings from 2002-2015. The results show that ①VOC emissions from the Beijing architechtural wall and waterproof coating was about 6914.2t·a-1 in 2015. The emissions from wall paint and waterproof coating were 2394.9 t·a-1and 4519.3 t·a-1, accounting for 34.6% and 65.4%, respectively. ②The spatial distribution of VOC emissions showed that emissions were mainly concentrated around the new cities being developed in the Chaoyang and Tongzhou districts. The district with the highest VOC emission is Tongzhou District, where the proportion of emission is about 13.2%. Following it are the Changping and Chaoyang districts, respectively, at 11.8% and 10.5%. ③In 2015, because of implementation of the standards < Indoor decorating and refurbishing materials-Limit of harmful substances of interior architectural coatings > (GB 18582-2008) and < Limit of harmful substances of exterior wall coatings > (GB 24408-2009), compared to the no control scenario, the VOCs emissions under control scenario was one where VOCs emissions were reduced by 8954.2 t. ④It follows that environmental management and control of the hazardous substance contents of architectural coatings can effectively control the VOC emission in China.

[Content Levels and Compositions Characteristics of Volatile Organic Compounds(VOCs) Emission from Architectural Coatings Based on Actual Measurement].

The content levels and composition characteristics of Volatile Organic Compounds (VOCs) from architectural coatings including interior wall coatings, exterior wall coatings, waterproofing coatings, anticorrosive coatings and floor coatings were investigated in this study. Architectural coating samples were obtained from manufacturers and retail outlets and the associated VOC contents and compositions were determined based on the domestic standard methods for measurement of VOCs in architectural coatings.The results showed that the VOC contents were 0-145 g·L-1 and 0-171 g·L-1 for interior and exterior wall coatings respectively. The proportion of samples that met the standards of HJ 2537-2014 were 90%, 80%, 96% and 94% for interior wall finishing coats, interior wall primary coats, exterior wall finishing coats and exterior wall primary coats respectively.The VOC content was found to be less than 10 g·L-1 for more than 90% of polymer-cement based waterproof coatings and acrylate polymer emulsion waterproof coatings respectively, and 1-324 g·L-1 for polyurethane waterproof coatings. The VOC contents for solvent-based coatings were found to be generally high, with VOC contents ranging from between 291-681 g·L-1 and 16-580 g·L-1 for solvent-based anticorrosive coatings and solvent-based floor coatings respectively, with great variation shown between different compositions and brands. The 1,2-propanediol and ethylene glycol were the most VOC in water-based coatings with methanol and 2-amino-2-methyl-1-propanol equal second. The main VOCs in solvent-based coatings were toluene, ethyl benzene, xylenes (total), ethyl acetate, butyl acetate and isobutyl acetate.

Transcriptome analysis of starch and sucrose metabolism across bulb development in Sagittaria sagittifolia.

Sagittaria sagittifolia L is an important bulb vegetable that has high nutritional and medical value. Bulb formation and development are crucial to Sagittaria sagittifolia; however, its sucrose metabolism is poorly understood and there are a lack of sufficient transcriptomic and genomic data available to fully understand the molecular mechanisms underlying bulb formation and development as well as the bulb transcriptome. Five cDNA libraries were constructed at different developmental stages and sequenced using high-throughput Illumina RNA sequencing. From approximately 63.53 Gb clean reads, a total of 60,884 unigenes, with an average length of 897.34 bp and N50 of 1.368 kb, were obtained. A total of 36,590 unigenes were successfully annotated using five public databases. Across different developmental stages, 4195, 827, 832, 851, and 1494 were differentially expressed in T02, T03, T04, T05, and T06 libraries, respectively. Gene ontology (GO) analysis revealed several differentially-expressed genes (DEGs) associated with catalytic activity, binding, and transporter activity. The Kyoto encyclopedia of genes and genomes (KEGG) revealed that these DEGs are involved in physiological and biochemical processes. RT-qPCR was used to profile the expression of these unigenes and revealed that the expression patterns of the DEGs were consistent with the transcriptome data. In this study, we conducted a comparative gene expression analysis at the transcriptional level using RNA-seq across the different developmental stages of Sagittaria sagittifolia. We identified a set of genes that might contribute to starch and sucrose metabolism, and the genetic mechanisms related to bulblet development were also explored. This study provides important data for future studies of the genetic and molecular mechanisms underlying bulb formation and development in Sagittaria sagittifolia.

Ozonation of azo dye Acid Red 14 in a microporous tube-in-tube microchannel reactor: decolorization and mechanism.

The ozonation of synthetic wastewater containing azo dye Acid Red 14 (AR 14) was investigated in a high-throughput microporous tube-in-tube microchannel reactor. The effects of design and operating parameters such as micropore size, annular channel width, liquid volumetric flow rate, ozone-containing gas volumetric flow rate, initial pH of the solution and initial AR 14 concentration on decolorization efficiency and ozone utilization efficiency were studied with the aim to optimize the operation conditions. An increase of the ozone-containing gas or liquid flow rate could greatly intensify the gas-liquid mass transfer. Reducing the micropore size and the annular channel width led to a higher mass transfer rate and was beneficial to decolorization. Decolorization efficiency increased with an increasing ozone-containing gas volumetric flow rate, as well as a decreasing liquid volumetric flow rate and initial AR 14 concentration. The optimum initial pH for AR 14 ozonation was determined as 9.0. The degradation kinetics was observed to be a pseudo-first-order reaction with respect to AR 14 concentration. The difference between the decolorization and COD removal efficiency indicated that many intermediates existed in AR 14 ozonation. The formation of six organic intermediates during ozonation was detected by GC/MS, while the concentration of nitrate and sulfate ions was determined by ion chromatography. The possible degradation mechanism of AR 14 in aqueous solution was proposed.