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降解VOCs的有机-无机光催化剂研究进展
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作者 徐晨晨 张奇 +1 位作者 许琦 袁海燕 《环境工程》 CAS CSCD 北大核心 2020年第1期28-36,共9页
挥发性有机物(VOCs)带来了诸多危害,VOCs治理已成研究热点。光催化降解VOCs因其低成本、无二次污染、节能、高矿化率等优点被广泛研究。TiO 2、Bi 2WO 6、MOF和量子点等光催化剂已应用于VOCs的降解,并在此基础上构建一种新型有机-无机... 挥发性有机物(VOCs)带来了诸多危害,VOCs治理已成研究热点。光催化降解VOCs因其低成本、无二次污染、节能、高矿化率等优点被广泛研究。TiO 2、Bi 2WO 6、MOF和量子点等光催化剂已应用于VOCs的降解,并在此基础上构建一种新型有机-无机复合光催化剂。在构建有机-无机复合光催化剂的过程中,从复合催化剂的有机及无机组分、催化剂结构、光生电子调控等方面研究,以期为制备降解VOCs的新型有机-无机复合光催化剂提供新的研究思路。 展开更多
关键词 有机 无机 光催化 VOCS 有机-无机光催化剂
Avian Community Density and Distribution Patterns among Nicaraguan Conventional and Organic Shade-Coffee Plantations 预览
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作者 Wayne J. Arendt R. Cary Tuckfield +4 位作者 Juan Carlos Martínez-Sánchez Jennifer L. Reidy Frank R. Thompson III Joseph M. Wunderle Jr. José Manuel Zolotoff 《农业科学(英文)》 2020年第1期27-53,共27页
We used a distance-sampling survey method and multivariate statistics to obtain a unique estimate of bird species density and seasonal variation in shade-coffee plantations. Our aim was to determine which cultivation ... We used a distance-sampling survey method and multivariate statistics to obtain a unique estimate of bird species density and seasonal variation in shade-coffee plantations. Our aim was to determine which cultivation practices among plantations contribute most to bird abundance. We conducted avian species counts at 200 points distributed across 10 shade-coffee plantations bordering the lower slopes of the Mombacho Volcano Natural Reserve, in western Nicaragua. We measured vegetation structure (coffee plants and overstory). We used principal components analysis (PCA) among 14 habitat variables to derive a single phyto-geoclimate summary measure (PGSM). We also used PCA to derive an avian abundance summary measure (AASM) from three bird survey variables, which proved to be a good predictor of bird density. We found higher bird species densities (AASM) in organic and traditional polyculture shade coffee plantations whose structurally complex and diverse overstory could be verified by PGSM. However, this finding was true only for birds that were habitat specialists. Our results provide further evidence for promoting organic coffee cultivation practices that maintain a structurally diverse overstory and help retain avian species richness and abundance in coffee plantations. 展开更多
关键词 Bird Density COFFEE Cultivation Practices MONOCULTURE ORGANIC POLYCULTURE Spatial Distribution Species Richness
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掺硼金刚石膜电极电化学消毒中有机物与大肠杆菌的相互作用 预览
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作者 田正顺 陈佰韬 +1 位作者 朱洪 李红娜 《北京农学院学报》 2020年第1期6-11,共6页
【目的】考察掺硼金刚石膜电极电化学体系同时降解有机物和消毒的效果及互相影响机制。【方法】研究掺硼金刚石膜电极电化学体系在有无大肠杆菌存在情况下,对含有邻苯二甲酸二甲酯、邻苯二甲酸二乙酯、苯酚、间苯二酚和间苯三酚5类有机... 【目的】考察掺硼金刚石膜电极电化学体系同时降解有机物和消毒的效果及互相影响机制。【方法】研究掺硼金刚石膜电极电化学体系在有无大肠杆菌存在情况下,对含有邻苯二甲酸二甲酯、邻苯二甲酸二乙酯、苯酚、间苯二酚和间苯三酚5类有机物的水溶液的电解效果,分别测定有机物的降解速率常数及大肠杆菌的对数灭活率;并以间苯二酚为例,探讨有机物浓度及酸碱度对共存体系中有机物的降解效果及大肠杆菌的对数灭活率的影响。【结果】在大肠杆菌存在的情况下,有机物的降解率上升,邻苯二甲酸二甲酯、邻苯二甲酸二乙酯、苯酚、间苯二酚和间苯三酚在大肠杆菌存在下的降解速率常数分别为0.774、0.972、0.990、1.818和7.902h-1,大于不含大肠杆菌时的降解速率常数(0.762、0.870、0.972、1.650、7.686h-1);与之相反,大肠杆菌的灭活变慢。初始浓度为0.030mmol/L时,0.230mg/L间苯二酚在5min内实现完全降解,而初始浓度为0.009mmol/L时只有0.080mg/L被降解;间苯二酚浓度从0.000到0.030mmol/L时,对应的大肠杆菌灭活率从5.40下降到3.24。酸碱度对共存体系有影响,pH=10体系与pH=7体系对间苯二酚的降解率快于pH=4体系。【结论】共存体系中有机物与微生物间的吸附,使得有机物的降解速率变快。同时,有机物的降解速率随其浓度的增加而减慢,但是降解量逐渐增加,在碱性(pH=10)条件下电解对有机物和大肠杆菌的处理效果最优。 展开更多
关键词 电化学消毒 掺硼金刚石膜电极 有机物 大肠杆菌
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Carbon-to-chlorophyll ratio and carbon content of phytoplankton community at the surface in coastal waters adjacent to the Zhujiang River Estuary during summer 预览
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作者 Xiaoyong Yu Jie Xu +3 位作者 Aimin Long Ruihuan Li Zhen Shi Qian P Li 《海洋学报:英文版》 SCIE CAS CSCD 2020年第2期123-131,共9页
Chlorophyll a(Chl a),particulate organic carbon(POC)and biogenic silica(BSi)were determined in coastal waters adjacent to the Zhujiang(Pearl)River Estuary(ZRE)during summer,in order to examine the C:Chl a ratio of phy... Chlorophyll a(Chl a),particulate organic carbon(POC)and biogenic silica(BSi)were determined in coastal waters adjacent to the Zhujiang(Pearl)River Estuary(ZRE)during summer,in order to examine the C:Chl a ratio of phytoplankton and phytoplankton carbon in the plume-impacted coastal waters during summer,as well as to assess the relative contribution of diatoms to the phytoplankton biomass,by the regression between Chl a,POC and BSi.Our results showed that the C:Chl a ratio(g/g)of phytoplankton was high(up to 142),likely due to high light intensity and nutrient limitation.The river plume input stimulated phytoplankton growth,especially diatoms,resulting in higher relative contribution of phytoplankton carbon(55%)and diatoms(34%)to POC in the plume-impacted region than those(33%and 13%)in high salinity area,respectively.Phytoplankton carbon(up to 538μg/L)in the plume-impacted region was much higher than that(<166μg/L)in high salinity area.Our findings were helpful to improve the biogeochemical model in coastal waters adjacent to the ZRE. 展开更多
关键词 chlorophyll a particulate organic carbon biogenic silica phytoplankton carbon DIATOMS
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热重-红外联用技术应用研究进展 预览
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作者 邵秋荣 孟昭建 +2 位作者 陈谷峰 方邢有 霍炜江 《化学分析计量》 CAS 2020年第1期121-127,共7页
对国内外热重-红外联用技术的应用进行综述和展望。主要介绍了热重-红外联用技术在能源清洁利用、化工及其它方面的应用。热重-红外联用技术应用广泛,可进行定量分析,可同时获得多种小分子气体的红外光谱信息。热重-红外联用技术面临的... 对国内外热重-红外联用技术的应用进行综述和展望。主要介绍了热重-红外联用技术在能源清洁利用、化工及其它方面的应用。热重-红外联用技术应用广泛,可进行定量分析,可同时获得多种小分子气体的红外光谱信息。热重-红外联用技术面临的挑战是难以分析弱红外吸收化合物,难以区分具有相似官能团的化合物,水对红外光谱有很大的影响。解决方案是热重-红外技术与质谱联用,增加被测化合物的分析准确性,采用惰性气体吹扫光学台及样品仓减少对测试结果的影响。热重-红外联用技术的发展趋势是热重-红外与质谱联用以提高测试准确性,测试条件规范化以避免检测误判。 展开更多
关键词 热重 红外 能源清洁 有机 无机
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Variation in glomalin in soil pro les and its associationwith climatic conditions,shelterbelt characteristics,and soilproperties in poplar shelterbelts of Northeast China 预览
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作者 Qiong Wang Wenjie Wang +2 位作者 Zhaoliang Zhong Huimei Wang Yujie Fu 《林业研究:英文版》 CAS CSCD 2020年第1期279-290,共12页
Glomalin-related soil protein(GRSP)sequesters large amounts of carbon and plays important roles in maintaining terrestrial soil ecosystem functions and ecological restoration;however,little is known about GRSP variati... Glomalin-related soil protein(GRSP)sequesters large amounts of carbon and plays important roles in maintaining terrestrial soil ecosystem functions and ecological restoration;however,little is known about GRSP variation in 1-m soil profiles and its association with stand characteristics,soil properties,and climatic conditions,hindering GRSP-related degraded soil improvement and GRSP evaluation.In this study,we sampled soils from 1-m profiles from poplar(Populus spp.)shelterbelts in Northeast China.GRSP contents were 1.8–2.0 times higher in the upper 40 cm soil layers than at 40–100 cm.GRSP-related soil organic carbon(SOC)sequestration in deeper soil layers was*1.2 times higher than in surface layers.The amounts of GRSP-related nutrients were similar throughout the soil profile.A redundancy analysis showed that in both surface and deeper layers,soil properties(pH,electrical conductivity,water,SOC,and soil nutrients)explained the majority of the GRSP variation(59.5–84.2%);the second-most-important factor in GRSP regulation was climatic conditions(temperature,precipitation,and altitude),while specific shelterbelt characteristics had negligible effects(<5%).Soil depth and climate indirectly affected GRSP features via soil properties,as manifested by structural equation model analysis.Our findings demonstrate that GRSP is important for carbon storage in deep soils,regardless of shelterbelt characteristics.Future glomalin assessments should consider these vertical patterns and possible regulating mechanisms that are related to soil properties and climatic changes. 展开更多
关键词 Soil depth Glomalin-related soil protein(GRSP) Soil organic carbon storage Climate change Soil improvement
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Study on Improvement of Flowering Cherry Soil in Nanshan Botanical Park of Chongqing City 预览
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作者 Fuyin XU Tao WAN 《农业生物技术:英文版》 CAS 2020年第1期57-59,共3页
[Objectives] This study was conducted to analyze the current status of soil quality in Chongqing and provide scientific data for the rejuvenation of flowering cherry in the botanical park of the city. [Methods] With t... [Objectives] This study was conducted to analyze the current status of soil quality in Chongqing and provide scientific data for the rejuvenation of flowering cherry in the botanical park of the city. [Methods] With the flowering cherry soil in Chongqing Botanical Park as the research object, the typical soil in this area was investigated and improved. [Results] After applying soil conditioners, the pH value of the surface soil decreased from 7.32 to 6.34, and the pH value of the bottom soil decreased from 7.52 to 6.77;and the surface soil organic matter increased from 35.2 to 54.1 g/kg, and the bottom soil organic matter increased from 15.7 to 26.3 g/kg. [Conclusions] The soil has strong buffering capacity, and it is difficult to achieve rapid adjustment of soil pH and organic matter in actual work. Soil improvement needs to be carried out step by step. After targeted improvement, further maintenance is required in the later stage. 展开更多
关键词 Flowering cherry Organic matter Acid-base property Soil improvement
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Review on Effects of Nitrogen on the Internal Quality ofPeach Fruit 预览
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作者 Zhisheng MA Yunyun JIA +1 位作者 Yuehui WANG Ruixia BAI 《农业生物技术:英文版》 CAS 2020年第1期80-84,100,共6页
On the basis of referring plenty of literatures, we summarized the research advance in effects of nitrogen on the internal quality of peach fruit. Most studies have shown that proper nitrogen application can improve i... On the basis of referring plenty of literatures, we summarized the research advance in effects of nitrogen on the internal quality of peach fruit. Most studies have shown that proper nitrogen application can improve internal quality of fruit, and excessive nitrogen application can reduce soluble solid and sugar contents of fruit, increase organic acid content, reduce fruit aroma, increase protein and amino acid contents, and increase or reduce vitamin C content. Relevant issues were discussed. 展开更多
关键词 Peach tree NITROGEN FRUIT Soluble solid content Organic acid Vitamin C Protein Amino acid
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Adsorption behaviour of Eu(Ⅲ) on natural bamboo fibres: effects of pH, humic acid, contact time, and temperature 预览
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作者 Tao Yu Jun Yang Ze-Yang Wang 《核技术:英文版》 SCIE CAS CSCD 2020年第1期32-41,共10页
To study the adsorption properties of organic functional groups in plant fibres and identify a highly efficient and affordable adsorbent for radioactive wastewater treatment,natural bamboo fibre(NBF)samples were prepa... To study the adsorption properties of organic functional groups in plant fibres and identify a highly efficient and affordable adsorbent for radioactive wastewater treatment,natural bamboo fibre(NBF)samples were prepared,and the adsorption properties of Eu(Ⅲ)on NBFs were studied under given experimental conditions.The effects of the pH,solid-to-liquid ratio,background ions,humic acid,contact time,and temperature on the adsorption behaviour of Eu(Ⅲ)on NBFs were investigated.Adsorption was greatly influenced by pH,and the adsorption curves presented two inflection points at pH≈7 and pH≈11.Moreover,while the ionic strength presented a negative effect at pH<7,the high ionic strength favoured adsorption at pH>7.During adsorption on NBFs,the–OH,C–H,O–H,C–O,and C=O were the main adsorption groups.Hydrolysis occurring on the NBF surface caused the adsorption process to become increasingly difficult at pH>7.The maximum adsorption capacity of NBFs was 147.6 mg/g at 308 K,and the adsorption could be described using the pseudo-second-order kinetic model.The adsorption of Eu(Ⅲ)on NBFs was a spontaneous and endothermic process according to the thermodynamic parameters of the process,and the adsorption thermodynamics could be well described using the Freundlich adsorption model.Therefore,NBFs were determined to be an efficient,inexpensive,and easily disposable sewage treatment material. 展开更多
关键词 ADSORPTION EU(III) Natural bamboo fibre Organic functional group
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有机物对电解锰电流效率的影响 预览
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作者 袁爱群 郭雨桐 +6 位作者 明宪权 李维健 陈南雄 吴晓丹 黄增尉 周泽广 韦冬萍 《湿法冶金》 CAS 北大核心 2020年第1期46-50,55,共6页
在自制电解液体系中,考察有机物湿法还原软锰矿所得浸出液中可能存在的8种有机物,即葡萄糖、蔗糖、甲酸、乙酸、腐殖酸、酒石酸、乌头酸、柠檬酸对锰电解电流效率的影响。结果表明:少量葡萄糖和蔗糖对锰电解电流效率影响较小,随葡萄糖... 在自制电解液体系中,考察有机物湿法还原软锰矿所得浸出液中可能存在的8种有机物,即葡萄糖、蔗糖、甲酸、乙酸、腐殖酸、酒石酸、乌头酸、柠檬酸对锰电解电流效率的影响。结果表明:少量葡萄糖和蔗糖对锰电解电流效率影响较小,随葡萄糖和蔗糖浓度增大,电解液黏度增大,进而影响电流效率;随甲酸、乙酸、腐殖酸浓度增大,电流效率呈下降趋势;酒石酸、乌头酸、柠檬酸质量浓度分别大于15、6、12g/L时,电流效率下降,进而导致电解锰质量下降;当柠檬酸质量浓度为12g/L时,可以减少二氧化硒添加量,柠檬酸和二氧化硒最佳添加量分别为6、0.015g/L,此时锰电解电流效率为77.9%。 展开更多
关键词 电解 有机物 电流效率 影响
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Theoretical Studies on Novel Gridspiroarenes: Structures, Noncovalent Interactions and Reorganization Energies
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作者 Lei Yang Cheng-Zhu Yin +11 位作者 Mohamad Akbar Ali Chao-Yang Dong Xin-Miao Xie Xiang-Ping Wu Jie Mao Yong-Xia Wang Yang Yu Ling-Hai Xie Lin-Yi Bian Jian-Min Bao Xue-Qin Ran Wei Huang 《中国化学:英文版》 SCIE CAS CSCD 2019年第9期915-921,共7页
Organic semiconductor materials with low reorganization energy have various applications such as in organic light-emitting diodes (OLEDs),organic field-effect transistor (OFETs) and organic solar cells (OSCs).In this ... Organic semiconductor materials with low reorganization energy have various applications such as in organic light-emitting diodes (OLEDs),organic field-effect transistor (OFETs) and organic solar cells (OSCs).In this work,we have designed a new class of gridspiroarenes (GS-SFX and GS-SITF) with #-shaped structures,which have novel crisscross geometrical structures compared to widely used spirocyclic arenes-SFX and SITF.The structure electronic properties,adiabatic ionization potentials (IPa),adiabatic electron affinities (EAa) and reorganization energies (λ) of GS-SFX and GS-SITF have been calculated using density functional theory (DFT) method.The calculated HOMO and LUMO spatial distributions suggest that GS-SFX and GS-SITF have better transport properties.The noncovalent interaction analysis shows the weak intramolecular interactions between their arms.The results indicate that the reorganization energies of GS-SFX and GS-SITF are significantly reduced compared to the dimer structures-DSFX and DSITF.Furthermore,the GS-SITF1 which is one of the isomers of GS-SITF exhibits the lowest values for λ(h)(0.067 eV) and λ(e)(0.153 eV).Therefore,we believe the predicted structure,electronic property,and reorganization energy are good indicator for transport materials.This work has systematically studied the effect of gridization,which provides insights to design organic semiconductor materials with excellent charge transport properties. 展开更多
关键词 ORGANIC LIGHT-EMITTING DIODES (OLEDs) ORGANIC FIELD-EFFECT TRANSISTOR (OFETs) ORGANIC solar cells (OSCs)
Performance of the hybrid growth sequencing batch reactor (HG-SBR)for biodegradation of phenol under various toxicity conditions
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作者 NikAthirah Yusoff Soon-An Ong +4 位作者 Li-Ngee Ho Yee-Shian Wong Farah Naemah Mohd Saad WanFadhilah Khalik Sin-Li Lee 《环境科学学报:英文版》 SCIE EI CAS CSCD 2019年第1期64-72,共9页
Hybrid growth microorganisms in sequencing batch reactors have proven effective for treating the toxic compound phenol,but the toxicity effect under different toxicity conditions has rarely been discussed.Therefore,th... Hybrid growth microorganisms in sequencing batch reactors have proven effective for treating the toxic compound phenol,but the toxicity effect under different toxicity conditions has rarely been discussed.Therefore,the performance of the HG-SBR under toxic,acute and chronic organic loading can provide the overall operating conditions of the system.Toxic organic loading (TOL)was monitored during the first 7 hr while introducing 50mg/L phenol to the system.The system was adversely affected with the sudden introduction of phenol to the virgin activated sludge,which caused a low degradation rate and high dissolved oxygen consumption during TOL.Acute organic loading (AOL)had significant effects at high phenol concentrations (600,800 1000mg/L).The specific oxygen uptake rate (SOUR)gradually decreased to 4.9mg O2/(g MLVSS.hr)at 1000mg/L of phenol compared to 12.74mg O2(g MLVSS-hr)for 200mg/L of phenol.The HG-SBR was further monitored during chronic organic loading (COL)over 67 days.The effects of organic loading were more apparent at 800mg/L and 1000mg/L phenol concentrations,as the removal range was between 22%-30% and 18%-46%respectively,which indicated the severe effects of COL. 展开更多
关键词 TOXIC ORGANIC LOADING Acute ORGANIC LOADING Chronic ORGANIC LOADING Phenol Sequencing BATCH reactor
A major step toward efficient and stable single-material organic solar cells
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作者 Jean Roncali 《中国科学:化学英文版》 SCIE EI CAS CSCD 2019年第9期1085-1086,共2页
Organic photovoltaics (OPV) can potentially combine low cost, lightness, flexibility and low environmental impact. In less than two decades, the power conversion efficiency(PCE) of OPV cells has increased from 1 to mo... Organic photovoltaics (OPV) can potentially combine low cost, lightness, flexibility and low environmental impact. In less than two decades, the power conversion efficiency(PCE) of OPV cells has increased from 1 to more than 15%thanks to parallel efforts in material design and device technology. 展开更多
关键词 ORGANIC photovoltaics (OPV) power conversion efficiency(PCE) STABLE single-material ORGANIC solar cells
Hexyl substitution of pentathienoacene toward a significant improvement in charge transport
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作者 Ping He Hantang Zhang +3 位作者 Chunhui Xu Yonggang Zhen Huanli Dong Wenping Hu 《中国化学快报:英文版》 SCIE CAS CSCD 2019年第4期903-905,共3页
A novel semiconductor, dihexyl-substituted pentathienoacene (C6-PTA) is designed and synthesized in five steps with the total yield up to 25.2%. The introduction of hexyl chains endow the thin film semiconductor with ... A novel semiconductor, dihexyl-substituted pentathienoacene (C6-PTA) is designed and synthesized in five steps with the total yield up to 25.2%. The introduction of hexyl chains endow the thin film semiconductor with about threefold increase in carrier mobility and one to three orders of magnitude improvement in current on/off ratio. Furthermore, single crystal FETs based on C6-PTA exhibited mobility up to 0.64 cm2 V-1 s-1, which is over 50 times higher than the thin film counterpart. The results indicate clearly that C6-PTA is a promising organic semiconductor with high stability. 展开更多
关键词 ORGANIC FIELD-EFFECT TRANSISTORS ORGANIC SEMICONDUCTORS Thienoacene Charge transport Stability
Adsorption kinetics of platinum group elements onto macromolecular organic matter in seawater 预览
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作者 Kai Liu Xuelu Gao +1 位作者 Qianguo Xing Fushan Chen 《海洋学报:英文版》 SCIE CAS CSCD 2019年第8期8-16,共9页
Adsorption kinetics of the interaction between Pt, Pd and Rh(defined here as platinum group elements, PGEs)ions and macromolecular organic compounds(MOCs,>10 kDa), including humic acid, carrageenan and bovine serum... Adsorption kinetics of the interaction between Pt, Pd and Rh(defined here as platinum group elements, PGEs)ions and macromolecular organic compounds(MOCs,>10 kDa), including humic acid, carrageenan and bovine serum albumin, and different cutoff fractions of natural organic matter(>1 kDa and >3 kDa) obtained from seawater using centrifugal ultrafiltration devices were investigated. For a given element, all the adsorption kinetics did not reach equilibrium except the interaction between Pt and >1 kDa cutoff, and between Pd and humic acid.For all the tested MOCs, the adsorption kinetics could be divided into two stages, a rapid adsorption process in the first 8 h and the desorption stage after the first 8 h until the equilibrium. The change trend of partition coefficient(log10Kd) values with experiment time was consistent with that of the kinetic curves. However, in the interaction between PGE ions and natural dissolved organic matter(NDOM), an obvious difference in the change trends of log10Kd and kinetic curves was observed. It indicated that the partition behavior of PGE ions interacting with NDOM in seawater was a combined effect of different organic constituents. The adsorption and log10Kd of PGEs in the >1 kDa NDOM fraction were higher and more stable than those in the >3 kDa NDOM fraction. The results also indicated that the 1–3 kDa NDOM may dominate the interaction between PGEs ions and NDOM. Moreover, no kinetic model could perfectly simulate the adsorption process. It indicated that the colloidal struction and morphology of MOCs or NDOM in seawater might be inhomogeneous. Hence, the interaction between PGE ions and organic matter in seawater was a complicated process and needs further research. 展开更多
关键词 ADSORPTION KINETICS PLATINUM group elements macromolecular ORGANIC compounds natural ORGANIC MATTER seawater
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Ozone-Biological Activated Carbon. Advanced Removal. Typical Persistent Organic pollutants from Micropolluted Source Water. Yangtze DeltaREgion 预览
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作者 Yaqiong Li 《探索-环境科学与技术》 2019年第1期18-21,共4页
Ozone-Biological Activated Carbon(O3-Bac). Studied. Advanced Removal. organics from micropolluted Source Water. water supply plant P located. J City. yangtze DeltaREgion..: Show, 19. 2%. permanganate Index10. 4%. tota... Ozone-Biological Activated Carbon(O3-Bac). Studied. Advanced Removal. organics from micropolluted Source Water. water supply plant P located. J City. yangtze DeltaREgion..: Show, 19. 2%. permanganate Index10. 4%. total organic carbon23. 0% UV254. Removed. advanced treatment. O3-Bac.Eight types. polycyclic aromatic Hydrocarbon(PAH)16 types. organochlorinated pesticides(OCPs), Five types. haloacetic Acids(Haas). Detected. Source Water.. Total concentrations. 53. 9-100. 06. 5-41. 8, 2. 5 × 10^3-1. 1 × 10^4Ng in L^-1... Advanced O3-Bac treatment removed 32. 5%. PAHs 25. 9%. OCPsGreatly improving. effluent. conventional Water Supply Process.HoweverHaas. mainly removed. conventional process. A removal. 33. 8%-0%.After. advanced treatment. O3-Bac. Chloroacetic acid slightly decreasedWhile the concentration of bromokinetic acid slightly created. 展开更多
关键词 Ozone-Biological Activated Carbon(O3.-Bac) POLYCYCLIC aromatic hydrocarbons(PAHs) ORGANIC Pesticides(OCPs) HALAL kids(Haas) Yangtza DeltaREgion Persistent ORGANIC pollutants(POPs)
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Influence of High Relative Humidity on Secondary Organic Carbon: Observations at a Background Site in East China
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作者 Linlin LIANG Guenter ENGLING +8 位作者 Yuan CHENG Xiaoye ZHANG Junying SUN Wanyun XU Chang LIU Gen ZHANG Hui XU Xuyan LIU Qianli MA 《气象学报:英文版》 SCIE CSCD 2019年第5期905-913,共9页
To investigate the impacts of relative humidity(RH) on secondary organic aerosol(SOA) concentrations and chemical reactions, the carbonaceous aerosol components [i.e., organic carbon(OC) and element carbon(EC)] were q... To investigate the impacts of relative humidity(RH) on secondary organic aerosol(SOA) concentrations and chemical reactions, the carbonaceous aerosol components [i.e., organic carbon(OC) and element carbon(EC)] were quantified in daily PM2.5 samples collected at a background site in East China during summer 2015. Based on the method of EC-tracer, the concentration of secondary organic carbon(SOC) demonstrated an obvious negative relationship with RH higher than 60%. Moreover, the ratio of SOC/EC also exhibited obvious decreasing trends with increasing RH, indicating negative effects for chemical production of SOA under high RH conditions. Due to high RH,photochemistry was weakened, gaseous oxidant concentrations was lowered(e.g., significantly decreased O3 levels),and the production rates of SOA were relatively low. On the other hand, because of more water uptake under higher RH conditions, the aerosol droplet acidity was reduced and enhancement of SOA formation by acidity was accordingly absent. In addition, high RH also plays an important role in changing viscosity of pre-existing aerosol coatings,which can affect reactive uptake yield of SOA. Overall, the results from this study imply that SOA production may be more associated with photochemical processes, while aqueous-phase chemistry is not very important for some SOA formation in a moist ambient environment. In the ambient atmosphere, oxidant concentrations, reaction rates,airborne species, etc., are highly variable. How do these factors affect SOA yields under given ambient environment warrants further detailed investigations. 展开更多
关键词 relative humidity organic aerosol secondary organic carbon(SOC) PHOTOCHEMISTRY AQUEOUS-PHASE
Carbon isotope and environmental changes in lakes in arid Northwest China
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作者 Weiguo LIU Xiangzhong LI +4 位作者 Zheng WANG Huangye WANG Hu LIU Bo ZHANG Huan ZHANG 《中国科学:地球科学英文版》 SCIE EI CAS CSCD 2019年第8期1193-1206,共14页
The stable carbon isotope composition(δ13 C) of lacustrine sediments, which can record changes in past environmental conditions such as the C4/C3 terrestrial vegetation composition, has been widely used for the recon... The stable carbon isotope composition(δ13 C) of lacustrine sediments, which can record changes in past environmental conditions such as the C4/C3 terrestrial vegetation composition, has been widely used for the reconstruction of terrestrial ecosystems and global climate changes. It has also been widely used in paleolimnological studies in arid northwestern China. In recent years, however, an increasing number of studies have enriched the environmental significance reflected by the stable carbon isotope geochemistry of lakes;therefore, the interpretation of lake δ13 C variations in paleoenvironmental reconstructions should be carefully evaluated from various aspects. In this paper, previous studies from the past several decades on the lacustrineδ13 C variations in arid northwestern China were reviewed, and the possible mechanisms of the δ13 C variations were discussed.Our study will provide a reference for the application of carbon isotope geochemistry in paleoenvironmental reconstructions. 展开更多
关键词 CARBON isotope Lake ARID region of NORTHWESTERN China Total ORGANIC CARBON ORGANIC biomarkers
Efficient organic solar cells achieved at a low energy loss
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作者 Wenrui Liu Jianyun Zhang +1 位作者 Shengjie Xu Xiaozhang Zhu 《科学通报:英文版》 SCIE EI CSCD 2019年第16期1144-1147,共4页
Organic photovoltaics(OPVs)have attracted much attention because of the advantages in low-cost and large-area fabrication and the great potentials in achieving flexible and semi-transparent devices(1)However,compared ... Organic photovoltaics(OPVs)have attracted much attention because of the advantages in low-cost and large-area fabrication and the great potentials in achieving flexible and semi-transparent devices(1)However,compared with inorganic and perovskite solar cells[2],OPVs show relatively low photoelectric conversion efficiencies,which is admittedly attributed to intrinsically low dielectric constants of organic materials[3]resulting in large energy losses(Eloss=EgqVoc,where Eg is the optical bandgap of the photoactive layer,Voc is the open-circuit voltage of photovoltaic devices and q is elementary charge). 展开更多
关键词 EFFICIENT ORGANIC SOLAR CELLS at a LOW energy LOSS ORGANIC photovoltaics
Carbonaceous aerosol in ambient air: Parallel measurements between water cyclone and carbon analyzer
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作者 Min-Suk Bae James J. Schwab +2 位作者 Da-Jeong Park Zang-Ho Shon Ki-Hyun Kim 《颗粒学报:英文版》 SCIE EI CAS CSCD 2019年第3期153-158,共6页
A water cyclone,developed to collect and preserve biological aerosols in a small liquid flow,was interfaced with a total organic carbon analyzer to measure the aerosol organic and inorganic carbon fractions.The total ... A water cyclone,developed to collect and preserve biological aerosols in a small liquid flow,was interfaced with a total organic carbon analyzer to measure the aerosol organic and inorganic carbon fractions.The total carbon was compared against parallel measurements of elemental carbon (EC) and organic carbon (OC) using a Sunset Real Time ECOC Analyzer between 12-29 January 2009.A National Institute for Occupational Safety and Health (NIOSH) like protocol for the measurements included four temperature steps ending at 840 ℃ for OC under a helium atmosphere followed by two temperature steps ramped to 850 ℃ for EC in a helium-oxygen atmosphere,Carbon data comparison between the water cyclone-TOC and the TOC measured by the analyzer indicated good agreement (r2 =0.82,linear regression slope =0.98,p < 0.001).Analyses of the relationship between total water organic carbon and OC,investigated using data sets from case studies spanning two different events,suggested it was possible to distinguish between the primary and secondary sources. 展开更多
关键词 WATER soluble ORGANIC CARBON Total ORGANIC CARBON CARBONACEOUS material
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