Brown carbon (BrC) plays a significant role in altering atmospheric radiation. Beyond biomass and biofuel combustion, recent studies identify fossil fuel sources – especially residential coal burning and vehicle exhaust – as major contributors to BrC. This underscores a gap in climate models, which often assume fossil fuel organic aerosols (OAs) are non-absorbing or treat all OA as light-scattering. In this study, we simulate BrC over the North China Plain (NCP) during a winter pollution event using the WRF-Chem model, incorporating explicit BrC absorption properties. The model aligns well with observed pollutant and aerosol levels, revealing an average near-surface BrC concentration of 5.2 µg m−3, contributing 16.4 % to aerosol absorption at 365 nm. Using a diagnostic adjoint approach, we estimate that BrC exerts a direct radiative effect (DRE) averaging −0.09 W m−2 at the top of the atmosphere, reducing the cooling effect of organic carbon by 28.0 % and producing a local warming effect of up to +0.40 W m−2. Coal combustion is the largest BrC source in the NCP in 2014, though secondary BrC also significantly impacts the regional radiation balance.

Abstract. Brown carbon (BrC) is recognized as a considerable factor changing the atmospheric radiation balance. In addition to the biomass and biofuel sources, both field observations and laboratory studies suggest that fossil fuel combustion is an important contributor to BrC. This highlights a critical gap in the treatment of BrC in climate models, which typically categorize organic aerosols (OA) from fossil fuels as non-absorbing or simplistically assume that all OA are light-scattering. Here we present a regional simulation of BrC during a highly polluted winter in North China Plain (NCP) by using the WRF-Chem model incorporating currently known BrC sources with explicit absorption properties. The modified model generally performs well in simulating air pollutants and aerosols species against observations. Our simulations show that the average near-surface mass concentration of BrC in the NCP is 4.8 μg m-3 and its contribution to the aerosol absorption optical depth at 365 nm is 11.2 %. A diagnostic adjoint method has been used to quantify the overall direct radiative effect (DRE) of BrC and contributions from various sources. We find that the DRE of BrC is predominantly negative with an average of -0.10 W m-2 at the top of the atmosphere (TOA) over the NCP, and consequently decreases the direct radiative cooling effect of OA by 24.0 % with a TOA warming of up to +0.34 W m-2. Our findings reveal that residential coal combustion is the principal contributor to the DRE of BrC in the NCP, and a noteworthy contribution from secondary BrC.

Column-integrated aerosol optical properties were derived systematically from measurements made in Xi'an, which is located in Guanzhong Plain of central China with a ground-based CIMEL sun photometer from May to November 2012. Aerosol optical depths (AODs), Ångström exponents, water vapor contents, and aerosol optical and micro-physical properties, including aerosol volume size distribution, complex refractive indices and single scattering albedo (SSA), were determined. Daily variations in AODs at 440 nm (τ440) generally followed those of the 24-hr PM2.5 mass concentrations, but there were differences in the relationships in summer and autumn. August showed the highest monthly τ440 (1.13) while the largest monthly Ångström exponent (α440–870 = 1.30) and water vapor content (Cw = 4.28) both occurred in July. Monthly averages of the aerosol size distributions showed the dominance of coarse mode aerosols, except in July and August, when the contribution of the accumulation and coarse modes were fairly comparable. Monthly changes in the complex refractive index (including both real and imaginary parts) and SSA were also studied, including their wavelength dependences; these analyses implied changes in the abundances of the aerosol types. Finally, an episode involving urban and dust aerosols was analyzed using sun photometer aerosol retrievals; MODIS images captured by Aqua satellite and average wind vectors from the NCEP operational global analyses were also considered in the case study.

The mass and light absorption contributions of organic carbon (OC), elemental carbon (EC), and mineral dust influence glacial melting and potentially contribute to climate change over the high Himalayas and Tibetan Plateau (HTP). Plateau-scale investigations of these components and their respective light absorption are limited due to the high altitude. In this study, we combined the analysis of major light-absorbing substances and their corresponding multiwavelength absorption to determine their specific contributions firstly. We investigated the spatial variations of total suspended particle (TSP) mass across the HTP, noting high contributions from dust, carbonaceous components, and secondary inorganic aerosols (SNA, including sulfate, nitrate, and ammonium). Enhanced levels of primary and secondary OC and SNA were observed in the marginal areas of the HTP, associated with high relative humidity (RH) and OX levels (O-3+NO2). EC was the primary contributor to light absorption, accounting for approximately 68%, 46%, and 64% in Ngari, Qinghai Lake, and Beiluhe, respectively. We found higher light-absorbing contributions from carbonaceous aerosols in the marginal areas compared to the central HTP site, particularly during the heating seasons (similar to 90%). Fugitive dust significantly contributed to TSP mass but not to light absorption. The concurrent constraints on the mass and optical properties of OC, EC, and dust in this study can help reduce uncertainties in climate models specific to the HTP.

以汾渭平原典型城市——咸阳为研究区域,利用地面空气质量监测数据和欧洲中期天气预报中心(ECMWF)发布的第五代全球气候再分析资料数据集(ERA5),分析了咸阳市2018-2020年3 a采暖期污染物浓度变化特征和不同污染程度下的气象条件,采用统计学方法分析各项污染物浓度与气象因素间的相关性,使用多元线性回归模型评价各气象因素对PM2.5浓度的影响程度,使用二元Logistic回归分析气象因素对PM2.5超标风险的影响.咸阳市采暖期首要污染物以细颗粒物(PM2.5)和可吸入颗粒物(PM10)为主,采暖期超标最多的污染物为PM2.5,超标天数逐年递减;PM10的日变化呈"双峰双谷"型,PM2.5的谷值出现在17:00且夜晚浓度较高.颗粒物浓度与相对湿度呈正相关,与风速、边界层高度、温度、气压呈负相关.多元线性回归预测模型显示PM2.5浓度预测值与实测值变化趋势保持一致,预测值的波动频率比实测值大,预测准确率为51.54％;二元Logistic回归模型显示:除相对湿度外,其他气象因素对PM2.5超标情况都是保护因素,边界层高度每增高1m,日均浓度超标风险降低0.7％;相对湿度每升高1％,日均浓度超标风险升高5.3％;温度每升高1℃,日均浓度超标风险降低19.8％;气压每升高1hPa,日均浓度超标风险降低9.7％.以上研究结果揭示了咸阳市采暖期主要气象因素对空气污染的影响程度,为我国北方城市今后的空气污染治理提供科学依据,为相关政策制定提供理论参考.

溶液制备PbS胶体量子点薄膜太阳能电池制作成本低且输出性能可观一直受到广泛关注.然而器件内部的吸收层与空穴传输功能层材料对环境的敏感性阻碍其发展应用,本文报道在大气环境下基于一次性油墨成膜路径制备PbS胶体量子点薄膜太阳能电池.研究证实以三水合乙酸铅为起始原料合成PbS胶体量子点的尺寸分布及其空气稳定性较好,后期在油墨中引入钝化剂3-巯基丙酸可进一步加强油墨的稳定性并提升电池性能.优化后器件相较对照组器件的电压(VOC)和填充因子(F.F.)均有所改善.最后在标准测试条件下,优化组器件的输出性能参数分别为:Jsc=23.961 mA/cm2、Voc=0.63 V、F.F.=64.7％及PCE=9.767％,且未封装条件下表现出良好的输出稳定性,30天后在相对湿度RH=10％以下空气环境下仍然保持原有92.48％效率值.

近年来,纳米尺度半导体材料由于其独特的物理化学性质在光电应用领域受到了广泛关注.在众多种类的纳米半导体材料中,Ⅰ-Ⅲ-Ⅵ2/Ⅰ-Ⅴ-Ⅵ2族三元金属硫化物由于其带隙易调、能通过化学计量比调控能带结构、毒性较低、原料来源广泛以及价格低廉等特点引起许多研究者的研究兴趣.其中AgBiS2作为该材料体系代表之一,具有合适的带隙、较高的吸收系数、耐潮湿等优异等特性,作为光电器件有源层材料具有较好的发展前景.首先结合AgBiS2材料结构基本性质对其光电特性进行阐述,总结应用于光电领域的AgBiS2纳米材料多样合成钝化处理途径及其在光电应用领域最新进展,并对其未来发展过程可能遇到的问题进行探讨.

Atmospheric black carbon (BC), primary and secondary brown carbon (BrCpri and BrCsec) are the light-absorbing carbonaceous aerosol components. The vertical changes in the BC and BrC distributions are not generally known. Here, we presented a study of the spectral light absorption properties, direct solar absorption, and potential source areas of BC and BrC at the foothill (375 m a.s.l.) and summit (2060 m a.s.l.) of Mt. Hua, China. More than tripled BC and BrC light absorption coefficient were observed at the foothill compared to the summit. The dominant carbonaceous light-absorbing was attributed to BC with the percentages of 77 % (foothill) and 79 % (summit), respectively. The light absorption coefficient and direct solar absorption of BrCpri were much higher than those of BrCsec at foothill, especially in winter. The enhancing contributions of BrCsec light absorption coefficient and direct solar absorption were observed with high RH and visibility at the summit. The light absorption properties of BC, BrCpri, and BrCsec may be attributed to the emissions, meteorological conditions, and photochemical oxidation. The inferred potential source spatial distributions of BC and BrCpri showed different patterns at the foothill and summit. The results underlined the primary emission effects (including BC and BrCpri) at the foothill and the importance of BrCsec at the summit, respectively.

The impacts of anthropogenic emissions on the reduction of source‐specific equivalent black carbon (eBC) aerosols and their direct radiative effects (DREs) were investigated during the lockdown of the coronavirus outbreak in a megacity of China in 2020. Five eBC sources were identified using a hybrid environmental receptor model. Results showed that biomass burning, traffic‐related emissions, and coal combustion were the dominant contributors to eBC. The generalized additive model indicated that the reduction of traffic‐related eBC during the lockdown was entirely attributed to the decrease of emissions. Decreased biomass‐burning activities and favorable meteorological factors are both important drivers for the biomass‐burning eBC reduction during the lockdown. A radiative transfer model showed that the DRE efficiency of eBC from biomass burning was the strongest, followed by coal combustion and traffic‐related emissions. This study highlights that aggressive reduction in the consumption of residential solid fuels would be effective in achieving climate change mitigation.

莫来石晶须具有耐高温、高强度、热膨胀系数小以及抗热震性能好等优点,在陶瓷复合材料中具有良好的应用前景.实验采用某公司自制莫来石晶须材料,采用X射线衍射仪(XRD)、扫描电镜(SEM)对该莫来石晶须材料进行了分析表征,并对其进行了一定程度的破碎、筛分和分散,以外加方式掺入到卫生洁具的坯体中,探讨了不同加入量以及不同筛分细度的莫来石材料对卫生洁具陶瓷机械强度的影响效果.

建筑节能材料成为降低建筑能耗的首选,墙体保温隔热材料具有巨大市场潜力和发展空间.蛭石基保温隔热材料是一种性能优异,可以广泛应用的新型保温材料.通过对文献调研,汇总了目前蛭石基保温材料的类型,从原料、胶凝材料和成型工艺等方面列举了蛭石基保温材料的实例,总结了蛭石基保温材料的发展现状,并分析其未来发展方向.

As one of the third-generation solar cells,colloidal quantum dot solar cells have attracted huge attentions owing to their simple preparation process and device flexibility.Notably,the surface passivation of the colloidal quantum dots for building the active layer has a critical impact on the device performances.This paper was aimed to briefly describe the recent research progress in surface passivation of the device-graded colloidal quantum dots and the effects of various ligands on device performances,with prospects of the future development trend.

陶瓷颜料中,红色颜料品种少且制备难度大.金红颜料是一种以金的胶体为着色剂的釉上彩颜料,它的呈色范围广,可获得棕色、粉红、黄色、紫红等色调.其色彩鲜艳、着色力强,是陶瓷釉上装饰颜料的名贵品种之一.本文概述了金红颜料的研究现状、呈色机理,综述了金红颜料的制备工艺、组成、金胶粒子的形貌与尺寸等因素对呈色的影响,并对金红颜料的应用现状进行了展望.

蒙脱石是一种黏土矿物,具有纳微米级粒径、大比表面积、特殊的纳米层间域、层间离子可交换性等物化性质,且分布广泛、储量丰富、价格低廉,可作为一种良好的环境材料用于对污水中各类污染物的吸附去除.蒙脱石对重金属、放射性核素,以及磷酸根等离子有较好的吸附能力.由于其表面极强的亲水性,蒙脱石矿物对弱极性和非极性有机污染物的吸附性能较差,限制了其应用范围.大量研究者选取适当的表面活性剂、硅烷偶联剂,通过插层、嫁接及柱撑等表面改性和结构改型处理,不仅大大提高其对无机离子的吸附能力,还可将蒙脱石亲水性表面变为疏水亲油表面,改变其表面张力与接触角,极大提升其对有机污染物的吸附性能.目前,对蒙脱石黏土矿物表面反应性的研究(包括黏土矿物的表面改性、层间域改造)已引起广泛关注,研究者通过不断寻求新技术、新方法,以扩展蒙脱石环境材料应用的广度和深度.利用离子交换、插层、柱撑、层间聚合等各种处理方法,把其他离子或化合物引入蒙脱石层间域,对其进行结构与表面性质的调控,使其表-界面物理化学性质发生相应的变化,制得具有不同功能性质的新型材料,可作为污染物的吸附剂、催化剂、混凝剂等广泛应用于环境污染修复领域.本文综述了近年来一些主要的蒙脱石矿物环境材料的构建方法及进展,探讨其微观结构对吸附性能的影响,阐述黏土矿物结构与吸附性能之间的构效关系,为开发新型高效环保的黏土矿物环境材料提供借鉴.

锡酸钡(BaSnO3)因其优异的介电性能在电解质陶瓷等领域已经得到广泛的应用.近几年,由于BaSnO3被发现可以替代TiO2作为钙钛矿太阳能电池中优质的电子传输层材料,逐渐吸引了国内外研究者们的关注.主要介绍了BaSnO3的晶体结构、制备方法及其掺杂改性等相关内容,并简要叙述了其国内外的研究现状以及未来的发展前景.

To investigate aerosol radiative effects, the Sun–Sky Radiometer Observation Network (SONET) has performed long-term observations of columnar atmospheric aerosol properties at 20 distributed stations around China. The aerosol direct radiative forcing (RF) and efficiency (RFE, the rate at which the atmosphere is forced per unit of aerosol optical depth) were estimated using radiative transfer model simulations based on the ground-based observations dating back to 2009. Results of multi-year monthly average RF illustrated that: the dust-dominant aerosol population at arid and semi-arid sites exerted moderate cooling effects (−8.0~−31.2 W/m2) at the top and bottom of atmosphere (TOA and BOA); RF at continental background site was very weak (−0.8~−2.9 W/m2); fine-mode dominant aerosols at urban and suburban sites exerted moderate cooling effects (−9.3~−24.1 W/m2) at TOA but more significant cooling effects (−19.4~−50.6 W/m2) at BOA; RF at coastal sites was comparable with values of urban sites (−5.5~−19.5 W/m2 at TOA, and −15.6~−44.6 W/m2 at BOA), owing to combined influences by marine and urban–industrial aerosols. Differences between RFE at TOA and BOA indicated that coarse-mode dominant aerosols at arid, semi-arid, and continental background sites were less efficient to warm the atmosphere; but fine-mode dominant aerosols at urban, suburban, and coastal sites were shown to be more efficient to heat the atmosphere.

以R2O-ZnO-B2O3-SiO2 (ZBS)体系为日用玻璃贴花装饰用无铅熔剂的基础配方,通过调整Na2O的含量,探讨Na2O含量对熔剂性能的影响.采用热膨胀仪、光泽度仪、SEM及FT-IR对样品的热膨胀系数、光泽度及显微结构进行表征,分析熔剂组成-结构-性能之间的关系和变化规律.结果 表明:样品的热膨胀系数α随Na2O的增加先增大后减小;光泽度、耐碱性随Na2O的增加而增大;耐酸性、彩烤温度随Na2O的增加而降低.当w(Na2O)=9.07％时,ZBS系统熔剂的α与玻璃基板的匹配性最好,光泽度能达到82,耐酸性最好,耐碱性甚至可以达到商业标准的4～5级.

The enrichment of mercury in sphalerite plays an important role in the migration and accumulation of Hg in the earth system. Despite Fe being the most common foreign ion in natural sphalerite, the effect of Fe substitution on the activity of sphalerite in the sequestration of Hg is not well understood. In this study, sphalerite and Fe-bearing sphalerite were synthesized by a coprecipitation method. Then, the structures and physico-chemistry properties were characterized, and their roles in the sequestration of gaseous He were compared. The Fe-bearing sphalerite exhibits better activity in the removal of gaseous Hg, with an average sequestration rate of 1.42 mu g g(-1) min(-1) compared to the sequestration rate of 0.27 mu g g(-1) min(-1) for sphalerite at 80 degrees C. The sequestration of Hg by sphalerite is dominated by a chemical adsorption mechanism involving the rupture of the Zn-S bond and formation of HgS. The Fe substitution coincorporates oxygen in the surface and bulk structure of sphalerite. This is evidenced by the occurrence of binding energy affiliated with surface lattice oxygen and the formation of massive H2O in the X-ray photoelectron spectra (XPS) and hydrogen temperature-programmed reduction (H-2-TPR) analyses of Fe-bearing sphalerite, respectively. The presence of lattice O weakens the adjacent Zn-S bond strength. This weakening is verified in the analyses of H-2-TPR, thermogravimetric and differential scanning calorimetry (TG-DSC), Raman spectra, and structure optimization and is especially obvious for the increase in the Zn-S bond length and the decrease in both the oxidation and reduction temperature for the Zn-S bond in Fe-bearing sphalerite. The weakening of the Zn-S bond strength favors its breakage to form HgS and improves the activity of sphalerite in the sequestration of gaseous Hg-0.

Aerosol optical depth (AOD) derived from satellite remote sensing is widely used to estimate surface PM2.5 (dry mass concentration of particles with an in situ aerodynamic diameter smaller than 2.5 µm) concentrations. In this research, a two-stage spatio-temporal statistical model for estimating daily surface PM2.5 concentrations in the Guanzhong Basin of China is proposed, using 6 km × 6 km AOD data available from the Visible Infrared Imaging Radiometer Suite (VIIRS) instrument as the main variable and meteorological factors, land-cover, and population data as auxiliary variables. The model is validated using a cross-validation method. The linear mixed effects (LME) model used in the first stage could be improved by using a geographically weighted regression (GWR) model or the generalized additive model (GAM) in the second stage, and the predictive capability of the GWR model is better than that of GAM. The two-stage spatio-temporal statistical model of LME and GWR successfully captures the temporal and spatial variations. The coefficient of determination (R2), the bias and the root-mean-squared prediction errors (RMSEs) of the model fitting to the two-stage spatio-temporal models of LME and GWR were 0.802, −0.378 µg/m3, and 12.746 µg/m3, respectively, and the model cross-validation results were 0.703, 1.451 µg/m3, and 15.731 µg/m3, respectively. The model prediction maps show that the topography has a strong influence on the spatial distribution of the PM2.5 concentrations in the Guanzhong Basin, and PM2.5 concentrations vary with the seasons. This method can provide reliable PM2.5 predictions to reduce the bias of exposure assessment in air pollution and health research.