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Source apportionment of PM

Wei WEN,Shuiyuan CHENG,Lei LIU,Gang WANG,Xiaoqi WANG

《环境科学与工程前沿（英文）》 2016年 第10卷 第5期 doi: 10.1007/s11783-016-0839-9

摘要： The new hybrid approaches for the source apportionment of PM were proposed. The hybrid approach can be used for source apportionment of secondary species. The metallurgy industry was the biggest contribution source to PM of Tangshan. In winter, the contribution from the coal-fired boilers was the largest one. The objective of this paper is to propose a hybrid approach for the source apportionment of primary and secondary species of PM in the city of Tangshan. The receptor-based PMF (Positive Matrix Factorization) is integrated with the emission inventory (EI) to form the first hybrid method for the source apportionment of the primary species. The hybrid CAMx-PSAT-CP (Comprehensive Air Quality Model with Extensions – Particulate Source Apportionment Technology – Chemical Profile) approach is then proposed and used for the source apportionment of the secondary species. The PM sources identified for Tangshan included the soil dust, the metallurgical industry, power plants, coal-fired boilers, vehicles, cement production, and other sources. It is indicated that the PM pollution is a regional issue. Among all the identified sources, the metallurgy industry was the biggest contribution source to PM , followed by coal-fired boilers, vehicles and soil dust. The other-source category plays a crucial role for PM , particularly for the formation of secondary species and aerosols, and these other sources include non-specified sources such as agricultural activities, biomass combustion, residential emissions, etc. The source apportionment results could help the local authorities make sound policies and regulations to better protect the citizens from the local and regional PM pollution. The study also highlights the strength of utilizing the proposed hybrid approaches in the identification of PM sources. The techniques used in this study show considerable promise for further application to other regions as well as to identify other source categories of PM .

关键词： Secondary species     Emission inventory     PM2.5     Source apportionment    

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THE 4C APPROACH AS A WAY TO UNDERSTAND SPECIES INTERACTIONS DETERMINING INTERCROPPING PRODUCTIVITY

《农业科学与工程前沿（英文）》 2021年 第8卷 第3期   页码 387-399 doi: 10.15302/J-FASE-2021414

摘要：

Modern agriculture needs to develop transition pathways toward agroecological, resilient and sustainable farming systems. One key pathway for such agroecological intensification is the diversification of cropping systems using intercropping and notably cereal-grain legume mixtures. Such mixtures or intercrops have the potential to increase and stabilize yields and improve cereal grain protein concentration in comparison to sole crops. Species mixtures are complex and the 4C approach is both a pedagogical and scientific way to represent the combination of four joint effects of Competition, Complementarity, Cooperation, and Compensation as processes or effects occurring simultaneously and dynamically between species over the whole cropping cycle. Competition is when plants have fairly similar requirements for abiotic resources in space and time, the result of all processes that occur when one species has a greater ability to use limiting resources (e.g., nutrients, water, space, light) than others. Complementarity is when plants grown together have different requirements for abiotic resources in space, time or form. Cooperation is when the modification of the environment by one species is beneficial to the other(s). Compensation is when the failure of one species is compensated by the other(s) because they differ in their sensitivity to abiotic stress. The 4C approach allows to assess the performance of arable intercropping versus classical sole cropping through understanding the use of abiotic resources.

 

关键词： compensation     competition     complementarity     cooperation     interspecific interactions     land equivalent ratio     light     nutrients     species mixtures     water    

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COMPARING PERFORMANCE OF CROP SPECIES MIXTURES AND PURE STANDS

《农业科学与工程前沿（英文）》 2021年 第8卷 第3期   页码 481-489 doi: 10.15302/J-FASE-2021413

摘要：

Intercropping is the planned cultivation of species mixtures on agricultural land. Intercropping has many attributes that make it attractive for developing a more sustainable agriculture, such as high yield, high resource use efficiency, lower input requirements, natural suppression of pests, pathogens and weeds, and building a soil with more organic carbon and nitrogen. Information is needed which species combinations perform best under different circumstances and which management is suitable to bring out the best from intercropping in a given production situation. The literature is replete with case studies on intercropping from across the globe, but evidence synthesis is needed to make this information accessible. Meta-analysis requires a careful choice of metric that is appropriate for answering the question at hand, and which lends itself for a robust meta-analysis. This paper reviews some metrics that may be used in the quantitative synthesis of literature data on intercropping.

 

关键词： intercropping     species mixtures     meta-analysis     metrics     indicators    

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Tracking in urban wastewater treatment plants in a cold region: Occurrence, species and infectivity

《环境科学与工程前沿（英文）》 2022年 第16卷 第9期 doi: 10.1007/s11783-022-1533-8

摘要：

• Cryptosporidium in WWTPs in a cold region was investigated in different seasons.

关键词： WWTPs     Cryptosporidium     Occurrence     Species     Infectivity     Low temperature    

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Mechanisms for simultaneous ozonation of sulfamethoxazole and natural organic matters in secondary effluent

《环境科学与工程前沿（英文）》 2021年 第15卷 第4期 doi: 10.1007/s11783-020-1368-0

摘要：

• SMX was mainly degraded by hydrolysis, isoxazole oxidation and double-bond addition.

关键词： Sulfamethoxazole     Ozonation     Natural organic matters     Secondary effluent     Degradation mechanism    

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IN VITRO ACTIVITY OF EXTRACTS OF FIVE MEDICINAL PLANT SPECIES ON PLANT PATHOGENIC FUNGI

《农业科学与工程前沿（英文）》 2021年 第8卷 第4期   页码 635-644 doi: 10.15302/J-FASE -2020343

摘要：

The antifungal effectiveness of extracts of five medicinal plant species was determined. The inhibitory activity of extracts of Eucalyptus tereticornis, Xanthium sibiricum, Artemisia argyi, Tupistra chinensis and Pyrola calliantha were evaluated against the mycelial growth of the plant pathogenic fungi Aspergillus niger, Botrytis cinerea, Penicillium digitatum, P. expansum, P. italicumand Rhizopus stolonifer. All plant extracts were prepared at 60°C using solvents (either water, 50% ethanol (v/v), 95% ethanol (v/v), ethyl acetate or petroleum ether). Fungicidal effects of all plants tested were confirmed. Different extracts from the same plant species gave different degrees of inhibition. All aqueous extracts had weak or no activity on all fungi tested. Ethyl acetate and 95% ethanol extracts from T. chinensis rhizomes gave greater inhibition and a broader spectrum inhibition than the other extracts. T. chinensis may have potential as a new natural fungicide and may be used for the preservation of agricultural and forestry products such as fruits and vegetables.

 

关键词： Botrytis cinerea / food preservation / plant diseases / plant pathogenic fungi / Tupistra chinensis    

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Physical and chemical processes of wintertime secondary nitrate aerosol formation

Qi YING

《环境科学与工程前沿（英文）》 2011年 第5卷 第3期   页码 348-361 doi: 10.1007/s11783-011-0343-1

摘要： The UCD/CIT model was modified to include a process analysis (PA) scheme for gas and particulate matter (PM) to study the formation of secondary nitrate aerosol during a stagnant wintertime air pollution episode during the California Regional PM /PM Air Quality Study (CRPAQS) where detailed measurements of PM components are available at a few sites. Secondary nitrate is formed in the urban areas from near the ground to a few hundred meters above the surface during the day with a maximum modeled net increase rate of 4 μg·m ·d during the study episode. The secondary nitrate formation rate in rural areas is lower due to lower NO . In the afternoon hours, near-surface temperature can be high enough to evaporate the particulate nitrate. In the nighttime hours, both the gas phase N O reactions with water vapor and the N O heterogeneous reactions with particle-bound water are important for secondary nitrate formation. The N O reactions are most import near the surface to a few hundred meters above surface with a maximum modeled net secondary nitrate increase rate of 1 μg·m ·d and are more significant in the rural areas where the O concentrations are high at night. In general, vertical transport during the day moves the nitrate formed near the surface to higher elevations. During the stagnant days, process analysis indicates that the nitrate concentration in the upper air builds up and leads to a net downward flux of nitrate through vertical diffusion and a rapid increase of surface nitrate concentration.

关键词： secondary nitrate aerosol     N2O5 heterogeneous reaction     process analysis    

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Two-echelon Emergency Response Problem and Simulation Considering Secondary Disasters

Han-peng Zhang,Yi Liao,Hui-xia Luo

《工程管理前沿（英文）》 2014年 第1卷 第3期   页码 318-321 doi: 10.15302/J-FEM-2014042

摘要： It is necessary for subsequent resource distribution planning that get expected relief time considering secondary disasters after natural disaster. The goal of this research is to develop a two-echelon emergency resource distribution model under condition of secondary disasters. Taking minimal maximize relief time as criterion of relief performance, we developed response strategies and simulation model to get the expected value. Numerical studies of this paper presented the result of response strategies.

关键词： simulation     secondary disasters     two-echelon vehicle routing model    

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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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Roles of various Ni species on TiO

Xiaoping CHEN, Jihai XIONG, Jinming SHI, Song XIA, Shuanglin GUI, Wenfeng SHANGGUAN

《能源前沿（英文）》 2019年 第13卷 第4期   页码 684-690 doi: 10.1007/s11708-018-0585-8

摘要： Low-cost nickels can be used as cocatalyst to improve the performance of photocatalysts, which may be promising materials applied in the field of photocatalytic water splitting. In this study, different nickel species Ni, Ni(OH) , NiO, NiO , and NiS are used to modified titanium dioxide (P25) to investigate their roles on the photocatalytic hydrogen evolution activities. UV-visible, X-ray diffraction (XRD), Brunner-Emmet-Teller (BET) measurements, transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) analysis etc. are employed to characterize the physical and chemical properties of catalysts. The results indicate that all the nickel species can improve the photocatalytic hydrogen production activity of P25. The P25 modified with NiO and NiS has more superior photocatalytic hydrogen evolution activities than those modified with other nickel species. The reason for this is that NiO and NiS can form p-n junctions with P25 respectively. In addition, NiO can be selectively deposited on the active sites of P25 via the photodeposition method and NiS is beneficial for H reacting with photo-excited electrons.

关键词： nickel species     TiO2     photocatalytic hydrogen evolution    

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PCDD/Fs emission, risk characterization, and reduction in China’s secondary copper production industry

Haiqian LI, Yonglong LU, Li LI

《环境科学与工程前沿（英文）》 2013年 第7卷 第4期   页码 589-597 doi: 10.1007/s11783-013-0495-2

摘要： Secondary copper production is one of the key polychlorinated dibenzo- -dioxins and dibenzofurans (PCDD/Fs) emission sources in China, but research and data on this issue are rare. In 2004, when the Stockholm Convention entered into force in China, PCDD/Fs emissions from secondary copper production contributed to 32.2% of the total release. In this paper, PCDD/Fs emission dynamics from secondary copper industry were discussed and cumulative risks were characterized. From 2004 to 2009, industrial policies played an indirect role in PCDD/Fs reduction, but its effects are still limited. The Yangtze River Delta, Pearl River Delta and central regions were among the top three of dioxin emissions from secondary copper production in China. Shanghai, Shandong, Zhejiang, and Jiangxi had comparatively higher accumulated risk and were recommended as the priority regions for promoting PCDD/Fs emission control in China. From 2009 to 2015, the PCDD/Fs emission dynamics in the secondary copper industry were presented through simulation. PCDD/Fs emission equations were established, resulting in the recommendation of control technology conversion rate at 30% for small scale smelters and 51%–57% for large and medium-sized enterprises in 2015. In conclusion, both indirect policy and direct control technology retrofitting should be integrated for more effective PCDD/Fs emission reduction in secondary copper industry.

关键词： polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs)     secondary copper production     emission     risk     China    

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Effects of different doses of cadmium on secondary metabolites and gene expression in Artemisia annua

null

《医学前沿（英文）》 2017年 第11卷 第1期   页码 137-146 doi: 10.1007/s11684-016-0486-3

摘要：

This study aims to elucidate the underlying molecular mechanisms of artemisinin accumulation induced by cadmium (Cd). The effects of different Cd concentrations (0, 20, 60, and 120 μmol/L) on the biosynthesis of Artemisia annua L. were examined. Intermediate and end products were quantified by HPLC-ESI-MS/MS analysis. The expression of key biosynthesis enzymes was also determined by qRT-PCR. The results showed that the application of treatment with 60 and 120 μmol/L Cd for 3 days significantly improved the biosynthesis of artemisinic acid, arteannuin B, and artemisinin. The concentrations of artemisinic acid, arteannuin B, and artemisinin in the 120 μmol/L Cd-treated group were 2.26, 102.08, and 33.63 times higher than those in the control group, respectively. The concentrations of arteannuin B and artemisinin in 60 μmol/L Cd-treated leaves were 61.10 and 26.40 times higher than those in the control group, respectively. The relative expression levels of HMGR, FPS, ADS, CYP71AV1, DBR2, ALDH1, and DXR were up-regulated in the 120 μmol/L Cd-treated group because of increased contents of artemisinic metabolites after 3 days of treatment. Hence, appropriate doses of Cd can increase the concentrations of artemisinic metabolites at a certain time point by up-regulating the relative expression levels of key enzyme genes involved in artemisinin biosynthesis.

关键词： Cd     secondary metabolites     gene expressions     Artemisia annua L.    

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Cooperative effect between copper species and oxygen vacancy in CeZrCuO catalysts for carbon monoxide

《化学科学与工程前沿（英文）》 2021年 第15卷 第6期   页码 1524-1536 doi: 10.1007/s11705-021-2106-2

摘要： The effects of Zr doping on the existence of Cu and the catalytic performance of Ce0.7−xZrxCu0.3O2 for CO oxidation were investigated. The characterization results showed that all samples have a cubic structure, and a small amount of Zr doping facilitates Cu2+ ions entering the CeO2 lattice, but excessive Zr doping leads to the formation of surface CuO crystals again. Thus, the number of oxygen vacancies caused by the Cu2+ entering the lattice (e.g., Cu2+–□–Ce4+; □: oxygen vacancy), and the amount of reducible copper species caused by CuO crystals, varies with the Zr doping. Catalytic CO oxidation tests indicated that the oxygen vacancy and the reducible copper species were the adsorption and activation sites of O2 and CO, respectively, and the cooperative effects between them accounted for the high CO oxidation activity. Thus, the samples x = 0.1 and 0.3, which possessed the most oxygen vacancy or reducible copper species, showed the best activity for CO oxidation, with full CO conversion obtained at 110 °C. The catalyst is also stable and has good resistance to water during the reaction.

关键词： Ce–Zr–Cu–O     CO oxidation     reducible copper species     oxygen vacancy     cooperative effect    

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Simple model of sludge thickening process in secondary settlers

Yuankai ZHANG,Hongchen WANG,Lu QI,Guohua LIU,Zhijiang HE,Songzhu JIANG

《环境科学与工程前沿（英文）》 2016年 第10卷 第2期   页码 319-326 doi: 10.1007/s11783-014-0758-6

摘要： In wastewater treatment plants (WWTPs), a secondary settler acts as a clarifier, sludge thickener, and sludge storage tank during peak flows and therefore plays an important role in the performance of the activated sludge process. Sludge thickening occurs in the lower portions of secondary clarifiers during their operation. In this study, by detecting the hindered zone from the complete thickening process of activated sludge, a simple model for the sludge thickening velocity, , describing the potential and performance of activated sludge thickening in the hindered zone was developed. However, sludge thickening in the compression zone was not studied because sludge in the compression zone showed limited thickening. This empirical model was developed using batch settling data obtained from four WWTPs and validated using measured data from a fifth WWTP to better study sludge thickening. To explore different sludge settling and thickening mechanisms, the curves of sludge thickening and sludge settling were compared. Finally, it was found that several factors including temperature, stirring, initial depth, and polymer conditioning can lead to highly concentrated return sludge and biomass in a biologic reactor.

关键词： wastewater treatment plants     secondary settler     sludge thickening     sludge settling     hindered zone    

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On the location of the secondary instantaneous poles in two-degree-of-freedom spherical mechanisms

Soheil ZARKANDI

《机械工程前沿（英文）》 2014年 第9卷 第1期   页码 34-40 doi: 10.1007/s11465-014-0290-1

摘要：

As the instant centers in planar mechanisms, the instantaneous poles (or instant poles, in brief) can be used for kinematic analysis in spherical mechanisms. One of the mandatory steps in this analysis is the determination of the location of these poles. This paper presents a theorem showing analytically that the locus of an unknown secondary instant pole in two-degree-of-freedom (2-DOF) spherical mechanisms is a great circle (GC). The exact location of the pole on its GC is obtained based on the configuration of the mechanism and velocity ratio of the two inputs. Moreover, using the results of the theorem, a geometrical technique is presented to determine the GC of the pole.

关键词： spherical mechanisms     instantaneous poles     great circle     angular velocity    

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标题 作者 时间 类型 操作

Source apportionment of PM

Wei WEN,Shuiyuan CHENG,Lei LIU,Gang WANG,Xiaoqi WANG

期刊论文

THE 4C APPROACH AS A WAY TO UNDERSTAND SPECIES INTERACTIONS DETERMINING INTERCROPPING PRODUCTIVITY

期刊论文

COMPARING PERFORMANCE OF CROP SPECIES MIXTURES AND PURE STANDS

期刊论文

Tracking in urban wastewater treatment plants in a cold region: Occurrence, species and infectivity

期刊论文

Mechanisms for simultaneous ozonation of sulfamethoxazole and natural organic matters in secondary effluent

期刊论文

IN VITRO ACTIVITY OF EXTRACTS OF FIVE MEDICINAL PLANT SPECIES ON PLANT PATHOGENIC FUNGI

期刊论文

Physical and chemical processes of wintertime secondary nitrate aerosol formation

Qi YING

期刊论文

Two-echelon Emergency Response Problem and Simulation Considering Secondary Disasters

Han-peng Zhang,Yi Liao,Hui-xia Luo

期刊论文

Formation of secondary inorganic aerosol in a frigid urban atmosphere

期刊论文

Roles of various Ni species on TiO

Xiaoping CHEN, Jihai XIONG, Jinming SHI, Song XIA, Shuanglin GUI, Wenfeng SHANGGUAN

期刊论文

PCDD/Fs emission, risk characterization, and reduction in China’s secondary copper production industry

Haiqian LI, Yonglong LU, Li LI

期刊论文

Effects of different doses of cadmium on secondary metabolites and gene expression in Artemisia annua

null

期刊论文

Cooperative effect between copper species and oxygen vacancy in CeZrCuO catalysts for carbon monoxide

期刊论文

Simple model of sludge thickening process in secondary settlers

Yuankai ZHANG,Hongchen WANG,Lu QI,Guohua LIU,Zhijiang HE,Songzhu JIANG

期刊论文

On the location of the secondary instantaneous poles in two-degree-of-freedom spherical mechanisms

Soheil ZARKANDI

期刊论文