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Local and regional contributions to PM in the Beijing 2022 Winter Olympics infrastructure areas duringhaze episodes

《环境科学与工程前沿（英文）》 2021年 第15卷 第6期 doi: 10.1007/s11783-021-1434-2

摘要：

• Regional transportation contributed more than local emissions during haze episodes.

关键词： 2022 Winter Olympics     PM2.5     Source apportionment    

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Improving simulations of sulfate aerosols during winter haze over Northern China: the impacts of heterogeneous

Meng Gao,Gregory R. Carmichael,Yuesi Wang,Dongsheng Ji,Zirui Liu,Zifa Wang

《环境科学与工程前沿（英文）》 2016年 第10卷 第5期 doi: 10.1007/s11783-016-0878-2

摘要： Incorporating the missing heterogeneous oxidation of S(IV) by NO into the WRF-Chem model. Sulfate production is not sensitive to increase in SO emission. The newly added reaction reproduces sulfate concentrations well during winter haze. We implemented the online coupled WRF-Chem model to reproduce the 2013 January haze event in North China, and evaluated simulated meteorological and chemical fields using multiple observations. The comparisons suggest that temperature and relative humidity (RH) were simulated well (mean biases are -0.2K and 2.7%, respectively), but wind speeds were overestimated (mean bias is 0.5 m?s ). At the Beijing station, sulfur dioxide (SO ) concentrations were overpredicted and sulfate concentrations were largely underpredicted, which may result from uncertainties in SO emissions and missing heterogeneous oxidation in current model. We conducted three parallel experiments to examine the impacts of doubling SO emissions and incorporating heterogeneous oxidation of dissolved SO by nitrogen dioxide (NO ) on sulfate formation during winter haze. The results suggest that doubling SO emissions do not significantly affect sulfate concentrations, but adding heterogeneous oxidation of dissolved SO by NO substantially improve simulations of sulfate and other inorganic aerosols. Although the enhanced SO to sulfate conversion in the HetS (heterogeneous oxidation by NO ) case reduces SO concentrations, it is still largely overestimated by the model, indicating the overestimations of SO concentrations in the North China Plain (NCP) are mostly due to errors in SO emission inventory.

关键词： Sulfate aerosols     Winter haze     WRF-Chem     Northern China    

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Secondary aerosol formation in winter haze over the Beijing-Tianjin-Hebei Region, China

Dongjie Shang, Jianfei Peng, Song Guo, Zhijun Wu, Min Hu

《环境科学与工程前沿（英文）》 2021年 第15卷 第2期 doi: 10.1007/s11783-020-1326-x

摘要： Abstract • Characteristics and interannual variation of aerosol pollution are illustrated. • Mechanisms of secondary aerosol formation in winter haze of North China are reviewed. • Directions in future studies of secondary aerosol formation are provided. Severe haze pollution occurs frequently in the winter over the Beijing-Tianjin-Hebei (BTH) region (China), exerting profound impacts on air quality, visibility, and human health. The Chinese Government has taken strict mitigation actions since 2013 and has achieved a significant reduction in the annual mean PM2.5 concentration over this region. However, the level of secondary aerosols during heavy haze episodes showed little decrease during this period. During heavy haze episodes, the concentrations of secondary aerosol components, including sulfate, nitrate and secondary organics, in aerosol particles increase sharply, acting as the main contributors to aerosol pollution. To achieve effective control of particle pollution in the BTH region, the precise and complete secondary aerosol formation mechanisms have been investigated, and advances have been made about the mechanisms of gas phase reaction, nucleation and heterogeneous reactions in forming secondary aerosols. This paper reviews the research progress in aerosol chemistry during haze pollution episodes in the BTH region, lays out the challenges in haze formation studies, and provides implications and directions for future research.

关键词： Secondary aerosol formation     Regional haze     Photochemical reaction     Aqueous reaction     Chemical mechanism    

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Characterization of bacterial communities during persistent fog and haze events in the Qingdao coastal

《环境科学与工程前沿（英文）》 2021年 第15卷 第3期 doi: 10.1007/s11783-020-1334-x

摘要：

• Light haze had little effect on bacterial communities.

关键词： Bacterial community     Persistent fog and haze     Particle size    

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Modeling radiative effects of haze on summer-time convective precipitation over North China: a case study

Xuying WANG, Bin ZHANG

《环境科学与工程前沿（英文）》 2016年 第10卷 第4期 doi: 10.1007/s11783-016-0840-3

摘要： We modeled the impact of haze radiative effects on precipitation in North China. Shortwave heating induced by haze radiative effects would reduce heavy rainfalls. Convection was the key factor that whether precipitation was enhanced or suppressed. Precipitation was often suppressed where CAPE, RH and updraft velocities were high. The impact of haze radiative effect on summertime 24-h convective precipitation over North China was investigated using WRF model (version 3.3) through model sensitivity studies between scenarios with and without aerosol radiative effects. The haze radiative effect was represented by incorporating an idealized aerosol optical profile, with AOD values around 1, derived from the aircraft measurement into the WRF shortwave scheme. We found that the shortwave heating induced by aerosol radiative effects would significantly reduce heavy rainfalls, although its effect on the post-frontal localized thunderstorm precipitation was more diverse. To capture the key factors that determine whether precipitation is enhanced or suppressed, model grids with 24-h precipitation difference between the two scenarios exceeding certain threshold (>30 mm or<-30 mm) were separated into two sets. Analyses of key meteorological variables between the enhanced and suppressed regimes suggested that atmospheric convection was the most important factor that determined whether precipitation was enhanced or suppressed during summertime over North China. The convection was stronger over places with precipitation enhancement over 30 mm. Haze weakened the convection over places with precipitation suppression exceeding 30 mm and caused less water vapor to rise to a higher level and thus further suppressed precipitation. The suppression of precipitation was often accompanied with relatively high convective available potential energy (CAPE), relative humidity (RH) and updraft velocities.

关键词： Haze     Aerosol radiative effects     Convective precipitation    

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霾的预测与预防问题

张 葵

《中国工程科学》 2015年 第17卷 第1期   页码 103-113

摘要：

针对低能见度天气的危害性，运用信息数字方法发现了霾的发生、发展与地热的联系和大气结构特征的改变。霾的预测、预防，需要正确把握近地低空大气的滚流状态和热结构特征。霾的形成既有人为排放也有自然界地热引发地下污染物和污浊气体的释放问题，地热可作为霾天气预报的先兆信息。大气环境的改善，需要人们改进排放技术，也需要研究自然污染源问题。

关键词： 能见度；霾；数字化预测；预防策略    

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International Winter Wheat Improvement Program: history, activities, impact and future

Alexey MORGOUNOV, Fatih OZDEMIR, Mesut KESER, Beyhan AKIN, Thomas PAYNE, Hans-Joachim BRAUN

《农业科学与工程前沿（英文）》 2019年 第6卷 第3期   页码 240-250 doi: 10.15302/J-FASE-2019261

摘要：

International Winter Wheat Improvement Program (IWWIP) was established in 1986 between the Government of Turkey and CIMMYT with three main objectives: (1) develop winter/facultative germplasm for Central and West Asia, (2) facilitate global winter wheat germplasm exchange, and (3) training wheat scientists. ICARDA joined the program in 1991 making it a three-way partnership that continues to work effectively. The germplasm developed by IWWIP as well as the winter wheat cultivars and lines received from global cooperators are assembled into international nurseries. These nurseries are offered annually to public and private entities (IWWIP website) and distributed to more than 100 cooperators in all continents. IWWIP impact has primarily been in new winter wheat cultivars combining broad adaptation, high yield potential, drought tolerance and disease resistance. A total of 93 IWWIP cultivars have been released in 11 countries occupying annually an estimated 2.5–3.0 Mha. IWWIP cooperation with researchers in Turkey, Central and West Asia and several US universities has resulted in a number of publications reviewed in this paper. Important IWWIP impacts include national inventories of wheat landraces in Turkey, Tajikistan and Uzbekistan, their collection, characterization, evaluation and utilization.

关键词： biotic and abiotic stresses     breeding     methodology     winter wheat    

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冬小麦产量的水肥耦合模型

翟丙年,李生秀

《中国工程科学》 2002年 第4卷 第9期   页码 69-74

摘要：

采用五因素五水平二次通用旋转组合设计方案（1/2实施），在盆栽条件下，不同水分状况氮素对冬小麦产量的影响。通过建立回归模型及对其进行解析和寻优分析，得出如下结论：各试验因素对冬小麦籽粒产量影响的大小顺序为土壤含水量＞越冬期施氮＞拔节期施氮＞灌浆期施氮＞苗期施氮。施氮关键时期为越冬期、拔节期；苗期施氮和土壤含水量及越冬期施氮和土壤含水量交互效应显著，其中越冬期施氮和土壤含水量比苗期施氮和土壤含水量交互作用更为显著。

关键词： 冬小麦     氮素     土壤含水量     水肥耦合     数学模型    

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Characteristics and mixing state of S-rich particles in haze episodes in Beijing

Jun Hu, Fengkui Duan, Kebin He, Yongliang Ma, Shuping Dong, Xiande Liu

《环境科学与工程前沿（英文）》 2016年 第10卷 第5期 doi: 10.1007/s11783-016-0861-y

摘要： Four types of S-rich particles are identified by SEM/FESEM-EDX With on-line observation, characteristics of S-rich particles are discovered Intensities of formation of S-rich particles are seasonally different Direct individual analysis using Scanning Electron Microscopy combined with online observation was conducted to examine the S-rich particles in PM of two typical polluted haze episodes in summer and winter from 2014 to 2015 in Beijing. Four major types of S-rich particles, including secondary CaSO particles (mainly observed in summer), S-rich mineral particles (SRM), S-rich water droplets (SRW) and (C, O, S)-rich particles (COS) were identified. We found the different typical morphologies and element distributions of S-rich particles and considered that (C, O, S)-rich particles had two major mixing states in different seasons. On the basis of the S-rich particles’ relative abundances, S concentrations and their relationships with PM as well as the seasonal comparison, we revealed that the S-participated formation degrees of SRM and SRW would enhance with increasing PM concentration. Moreover, C-rich matter and sulfate had seasonally different but significant impacts on the formation of COS.

关键词： S-rich particles     Morphology     Element distribution     Mixing state    

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Lodging resistance and yield potential of winter wheat: effect of planting density and genotype

Yonggui XIAO,Jianjun LIU,Haosheng LI,Xinyou CAO,Xianchun XIA,Zhonghu HE

《农业科学与工程前沿（英文）》 2015年 第2卷 第2期   页码 168-178 doi: 10.15302/J-FASE-2015061

摘要： Improved lodging resistance is important for achieving high yield in irrigated environments. This study was conducted to determine genotypic variation in lodging resistance and related morphological traits among winter wheat cultivars planted at two densities, and to identify key traits associated with lodging resistance. Lodging performance of 28 genotypes, including 24 released cultivars and four advanced lines, was evaluated at 250 plants per square meter and 500 plants per square meter in Shandong province during the 2008–2009 and 2009–2010 crop seasons. At the higher density, the average grain yield was 2.6% higher, even though lodging score rose by as much as 136%. The higher planting density increased lodging through increased leaf area index (LAI), plant height, center of gravity and length of basal internodes, and reduced grain weight per spike and diameter of the lower two stem internodes. LAI, center of gravity and diameter of first internodes, as the important indicators for lodging resistance, were significantly correlated with lodging score, with = 0.62, 0.59 and −0.52 ( <0.01), respectively. Plant pushing resistance was significantly associated with diameter and length of the first internodes ( = 0.71–0.77, <0.01), indicating it could be used to assess the strength of the lower stem. Higher planting density could be used to select genotypes with lodging resistance in irrigated environments. Cultivars carrying high plant density tolerance and high yield potential, such as Jimai 22 and Liangxing 66, were recommended as leading cultivars for production as well as elite crossing parents for further increasing yield potential in the Yellow and Huai Valleys Winter Wheat Zone in China.

关键词： common wheat     yield potential     lodging performance     pushing resistance     leaf area index    

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Purification of ice structuring protein complexes from winter wheat using Triton X-114 phase partitioning

Huaneng XU, Haiying CHEN, Weining HUANG,

《化学科学与工程前沿（英文）》 2009年 第3卷 第4期   页码 383-385 doi: 10.1007/s11705-009-0249-7

摘要： Ice structuring proteins (ISPs) isolated from the cold-acclimated plants have a great potential in improving the quality of frozen foods. The purification of ISP complexes from winter wheat was achieved using an aqueous two-phase system of Triton X-114. The highly reactive phenols were removed, and the ISP complexes remained in the aqueous phase after phase separation. The ISP complexes treated by this procedure retained higher thermal hysteresis activity than those treated by ammonium sulfate method. The phase separation technique provides a simple and mild way for removing phenols from ISP complexes.

关键词： separation technique     thermal hysteresis     cold-acclimated     purification     X-114    

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Primary assessment of the diversity of Omicron sublineages and the epidemiologic features of autumn/winter

《医学前沿（英文）》 2023年 第17卷 第4期   页码 758-767 doi: 10.1007/s11684-022-0981-7

摘要： With the recent ongoing autumn/winter 2022 COVID-19 wave and the adjustment of public health control measures, there have been widespread SARS-CoV-2 infections in Chinese mainland. Here we have analyzed 369 viral genomes from recently diagnosed COVID-19 patients in Shanghai, identifying a large number of sublineages of the SARS-CoV-2 Omicron family. Phylogenetic analysis, coupled with contact history tracing, revealed simultaneous community transmission of two Omicron sublineages dominating the infections in some areas of China (BA.5.2 mainly in Guangzhou and Shanghai, and BF.7 mainly in Beijing) and two highly infectious sublineages recently imported from abroad (XBB and BQ.1). Publicly available data from August 31 to November 29, 2022 indicated an overall severe/critical case rate of 0.035% nationwide, while analysis of 5706 symptomatic patients treated at the Shanghai Public Health Center between September 1 and December 26, 2022 showed that 20 cases (0.35%) without comorbidities progressed into severe/critical conditions and 153 cases (2.68%) with COVID-19-exacerbated comorbidities progressed into severe/critical conditions. These observations shall alert healthcare providers to place more resources for the treatment of severe/critical cases. Furthermore, mathematical modeling predicts this autumn/winter wave might pass through major cities in China by the end of the year, whereas some middle and western provinces and rural areas would be hit by the upcoming infection wave in mid-to-late January 2023, and the duration and magnitude of upcoming outbreak could be dramatically enhanced by the extensive travels during the Spring Festival (January 21, 2023). Altogether, these preliminary data highlight the needs to allocate resources to early diagnosis and effective treatment of severe cases and the protection of vulnerable population, especially in the rural areas, to ensure the country’s smooth exit from the ongoing pandemic and accelerate socio-economic recovery.

关键词： SARS-CoV-2     COVID-19     Omicron     genomic epidemiology    

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Improving water use efficiency in grain production of winter wheat and summer maize in the North China

Xiying ZHANG,Wenli QIN,Juanna XIE

《农业科学与工程前沿（英文）》 2016年 第3卷 第1期   页码 25-33 doi: 10.15302/J-FASE-2016090

摘要： Reducing irrigation water use by improving water use efficiency (WUE) in grain production is critical for the development of sustainable agriculture in the North China Plain (NCP). This article summarizes the research progresses in WUE improvement carried out at the Luancheng station located in the Northern part of NCP for the past three decades. Progresses in four aspects of yield and WUE improvement are presented, including yield and WUE improvement associated with cultivar selection, irrigation management for improving yield and WUE under limited water supply, managing root system for efficient soil water use and reducing soil evaporation by straw mulch. The results showed that annual average increase of 0.014 kg·m for winter wheat and 0.02 kg·m in WUE were observed for the past three decades, and this increase was largely associated with the improvement in harvest index related to cultivar renewal and an increase in chemical fertilizer use and soil fertility. The results also indicated that deficit irrigation for winter wheat could significantly reduce the irrigation water use, whereas the seasonal yield showed a smaller reduction rate and WUE was significantly improved. Straw mulching of summer maize using the straw from winter wheat could reduce seasonal soil evaporation by 30–40 mm. With new cultivars and improved management practices it was possible to further increase grain production without much increase in water use. Future strategies to further improve WUE are also discussed.

关键词： harvest index     cultivar selection     deficit irrigation     root water uptake     straw mulching    

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基于暗通道先验的单幅图像快速去雾算法 Research Articles

Bo-xuan YUE, Kang-ling LIU, Zi-yang WANG, Jun LIANG

《信息与电子工程前沿（英文）》 2019年 第20卷 第8期   页码 1109-1118 doi: 10.1631/FITEE.1700148

摘要： 在雾气中，可见光的散射降低了图像可见度。目前，去雾仍是图像处理应用的一个挑战。为实现去雾，提出一种基于单个像素的去雾加速算法。不同于基于区块的方法，所提方法分别估计每个区域的变换矩阵和大气光参数，其中加速的关键在于所有参数能在一次遍历中获得。然后，对传输映射进行双边过滤，恢复像素之间的关系。通过线性模糊模型恢复后，对恢复的图像进行调整，以提高对比度、光照强度和饱和度，尤其是补偿由相应波长引起的不同通道的光强误差。实验结果表明，该方法在处理速率方面优于已有的最先进去雾算法。与其他去雾方法比较和引入定量准则（峰信噪比、可检测边际速率、信息熵差）验证该方法有效。

关键词： 去雾；暗通道先验；雾图像模型；双边滤波    

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Formation of secondary inorganic aerosol in a frigid urban atmosphere

《环境科学与工程前沿（英文）》 2022年 第16卷 第2期 doi: 10.1007/s11783-021-1452-0

摘要：

•Harbin showed relatively high threshold RH (80%) for apparent increase of SOR.

关键词： Haze     Sulfate     Nitrate     Heterogeneous chemistry     Biomass burning     Northeast China    

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标题 作者 时间 类型 操作

Local and regional contributions to PM in the Beijing 2022 Winter Olympics infrastructure areas duringhaze episodes

期刊论文

Improving simulations of sulfate aerosols during winter haze over Northern China: the impacts of heterogeneous

Meng Gao,Gregory R. Carmichael,Yuesi Wang,Dongsheng Ji,Zirui Liu,Zifa Wang

期刊论文

Secondary aerosol formation in winter haze over the Beijing-Tianjin-Hebei Region, China

Dongjie Shang, Jianfei Peng, Song Guo, Zhijun Wu, Min Hu

期刊论文

Characterization of bacterial communities during persistent fog and haze events in the Qingdao coastal

期刊论文

Modeling radiative effects of haze on summer-time convective precipitation over North China: a case study

Xuying WANG, Bin ZHANG

期刊论文

霾的预测与预防问题

张 葵

期刊论文

International Winter Wheat Improvement Program: history, activities, impact and future

Alexey MORGOUNOV, Fatih OZDEMIR, Mesut KESER, Beyhan AKIN, Thomas PAYNE, Hans-Joachim BRAUN

期刊论文

冬小麦产量的水肥耦合模型

翟丙年,李生秀

期刊论文

Characteristics and mixing state of S-rich particles in haze episodes in Beijing

Jun Hu, Fengkui Duan, Kebin He, Yongliang Ma, Shuping Dong, Xiande Liu

期刊论文

Lodging resistance and yield potential of winter wheat: effect of planting density and genotype

Yonggui XIAO,Jianjun LIU,Haosheng LI,Xinyou CAO,Xianchun XIA,Zhonghu HE

期刊论文

Purification of ice structuring protein complexes from winter wheat using Triton X-114 phase partitioning

Huaneng XU, Haiying CHEN, Weining HUANG,

期刊论文

Primary assessment of the diversity of Omicron sublineages and the epidemiologic features of autumn/winter

期刊论文

Improving water use efficiency in grain production of winter wheat and summer maize in the North China

Xiying ZHANG,Wenli QIN,Juanna XIE

期刊论文

基于暗通道先验的单幅图像快速去雾算法

Bo-xuan YUE, Kang-ling LIU, Zi-yang WANG, Jun LIANG

期刊论文

Formation of secondary inorganic aerosol in a frigid urban atmosphere

期刊论文