期刊文献+
共找到224篇文章
< 1 2 12 >
每页显示 20 50 100
Integrating Levels of Hierarchical Organization in Porous Organic Molecular Materials 被引量:1
1
作者 Jesus Ferrando‑Soria Antonio Fernandez 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第5期134-153,共20页
Porous organic molecular materials(POMMs)are an emergent class of molecular-based materials characterized by the formation of extended porous frameworks,mainly held by non-covalent interactions.POMMs represent a varie... Porous organic molecular materials(POMMs)are an emergent class of molecular-based materials characterized by the formation of extended porous frameworks,mainly held by non-covalent interactions.POMMs represent a variety of chemical families,such as hydrogen-bonded organic frameworks,porous organic salts,porous organic cages,C-H···πmicroporous crystals,supramolecular organic frameworks,π-organic frameworks,halogen-bonded organic framework,and intrinsically porous molecular materials.In some porous materials such as zeolites and metal organic frameworks,the integration of multiscale has been adopted to build materials with multifunctionality and optimized properties.Therefore,considering the significant role of hierarchy in porous materials and the growing importance of POMMs in the realm of synthetic porous materials,we consider it appropriate to dedicate for the first time a critical review covering both topics.Herein,we will provide a summary of literature examples showcasing hierarchical POMMs,with a focus on their main synthetic approaches,applications,and the advantages brought forth by introducing hierarchy. 展开更多
关键词 Porous organic molecular materials HIERARCHY Hydrogen-bonded organic frameworks Porous cages FULLERENE
在线阅读 下载PDF
A low redox potential and long life organic anode material for sodium-ion batteries 被引量:1
2
作者 Zhi Li Yang Wei +7 位作者 Kang Zhou Xin Huang Xing Zhou Jie Xu Taoyi Kong Junwei Lucas Bao Xiaoli Dong Yonggang Wang 《Journal of Energy Chemistry》 2025年第1期557-564,共8页
Sodium-ion batteries (SIBs) with organic electrodes are an emerging research direction due to the sustainability of organic materials based on elements like C,H,O,and sodium ions.Currently,organic electrode materials ... Sodium-ion batteries (SIBs) with organic electrodes are an emerging research direction due to the sustainability of organic materials based on elements like C,H,O,and sodium ions.Currently,organic electrode materials for SIBs are mainly used as cathodes because of their relatively high redox potentials(>1 V).Organic electrodes with low redox potential that can be used as anode are rare.Herein,a novel organic anode material (tetrasodium 1,4,5,8-naphthalenetetracarboxylate,Na_(4)TDC) has been developed with low redox potential (<0.7 V) and excellent cyclic stability.Its three-sodium storage mechanism was demonstrated with various in-situ/ex-situ spectroscopy and theoretical calculations,showing a high capacity of 208 mAh/g and an average decay rate of merely 0.022%per cycle.Moreover,the Na_(4)TDC-hard carbon composite can further acquire improved capacity and cycling stability for 1200 cycles even with a high mass loading of up to 20 mg cm^(-2).By pairing with a thick Na_(3)V_(2)(PO_(4))_(3)cathode (20.6 mg cm^(-2)),the as-fabricated full cell exhibited high operating voltage (2.8 V),excellent rate performance and cycling stability with a high capacity retention of 88.7% after 200 cycles,well highlighting the Na_(4)TDC anode material for SIBs. 展开更多
关键词 Organic anode material Low redox potential Composite anode Sodium-ion batteries
在线阅读 下载PDF
Polycarbonyl conjugated porous polyimide as anode materials for high performance sodium-ion batteries
3
作者 Liangju Zhao Shiyu Qin +7 位作者 Fei Wu Limin Zhu Qing Han Lingling Xie Xuejing Qiu Hongliang Wei Lanhua Yi Xiaoyu Cao 《Chinese Chemical Letters》 2025年第8期498-504,共7页
Conjugated microporous polymers(CMPs)have attracted considerable attention as potential organic anode materials for sodium-ion batteries(SIBs)due to their flexible chemical structure,high porosity,environmental friend... Conjugated microporous polymers(CMPs)have attracted considerable attention as potential organic anode materials for sodium-ion batteries(SIBs)due to their flexible chemical structure,high porosity,environmental friendliness,and cost effectiveness.However,the inherent shortcomings of organic electrodes,such as low conductivity,high solubility in electrolyte,narrow material utilization,etc.,limit their further development.In this work,we successfully prepared a novel porous polyimide PPD containing multicarbonyl active centers via the polycondensation of pyromellitic dianhydride(PMDA)and2,6-diaminoanthraquinone(DAAQ).The stable conjugated structure and multiple redox centers give the polymer high reversible specific capacity(244.6 m Ah/g after 100 cycles at 100 m A/g),ultra-long cycle stability(100.7 m Ah/g after 2000 cycles at 1.0 A/g),and predominant rate capability.Meanwhile,the sodium storage mechanism of the electrode materials during the charging and discharging process is investigated by ex-situ XPS/FTIR analysis.Due to the exceptional electrochemical properties and simple synthesis method,this work may shed light on the preparation of polyimide-based anodes for high specific capacity and rate capability secondary batteries. 展开更多
关键词 Sodium-ion batteries Porous polyimide Polycarbonyl Organic materials Anodes
原文传递
Facile synthesis of phenazine-conjugated polymer material with extraordinary proton-storage redox capability
4
作者 Renyuan Wang Lei Ke +5 位作者 Houxiang Wang Yueheng Tao Yujie Cui Peipei Zhang Minjie Shi Xingbin Yan 《Chinese Chemical Letters》 2025年第5期705-710,共6页
Aqueous proton batteries(APBs)embody a compelling alternative in the realm of economical and reliable energy technologies by virtue of their distinctive“Grotthuss mechanism”.Sustainable production and adjustable mol... Aqueous proton batteries(APBs)embody a compelling alternative in the realm of economical and reliable energy technologies by virtue of their distinctive“Grotthuss mechanism”.Sustainable production and adjustable molecular structure make organic polymers a promising choice for APB electrodes.However,inadequate proton-storage redox capability currently hinders their practical implementation.To address this issue,we introduce a pioneering phenazine-conjugated polymer(PPZ),synthesized through a straightforward polymerization process,marking its debut in APB applications.The inclusion of N-heteroaromatic fused-ring in the extendedπ-conjugated framework not only prevents the dissolution of redox-active units but also refines the energy bandgap and electronic properties,endowing the PPZ polymer with both structural integrity and enhanced redox activity.Consequently,the PPZ polymer as an electrode material achieves a remarkable proton-storage capacity of 211.5 mAh/g,maintaining a notable capacity of 158.3 mAh/g even under a high rate of 8 A/g with a minimal capacity fade of merely 0.00226%per cycle.The rapid,stable and impressive redox behavior is further elucidated through in-situ techniques and theoretical calculations.Ultimately,we fabricate an APB device featuring satisfactory electrochemical attributes with an extraordinary longevity over 10,000 cycles,thereby affirming its auspicious potential for eminent applications. 展开更多
关键词 Aqueous battery Molecular design Organic material Proton storage Electrochemical mechanism
原文传递
Multifunctional Organic Materials,Devices,and Mechanisms for Neuroscience,Neuromorphic Computing,and Bioelectronics
5
作者 Felix L.Hoch Qishen Wang +1 位作者 Kian-Guan Lim Desmond K.Loke 《Nano-Micro Letters》 2025年第10期525-550,共26页
Neuromorphic computing has the potential to overcome limitations of traditional silicon technology in machine learning tasks.Recent advancements in large crossbar arrays and silicon-based asynchronous spiking neural n... Neuromorphic computing has the potential to overcome limitations of traditional silicon technology in machine learning tasks.Recent advancements in large crossbar arrays and silicon-based asynchronous spiking neural networks have led to promising neuromorphic systems.However,developing compact parallel computing technology for integrating artificial neural networks into traditional hardware remains a challenge.Organic computational materials offer affordable,biocompatible neuromorphic devices with exceptional adjustability and energy-efficient switching.Here,the review investigates the advancements made in the development of organic neuromorphic devices.This review explores resistive switching mechanisms such as interface-regulated filament growth,molecular-electronic dynamics,nanowire-confined filament growth,and vacancy-assisted ion migration,while proposing methodologies to enhance state retention and conductance adjustment.The survey examines the challenges faced in implementing low-power neuromorphic computing,e.g.,reducing device size and improving switching time.The review analyses the potential of these materials in adjustable,flexible,and low-power consumption applications,viz.biohybrid spiking circuits interacting with biological systems,systems that respond to specific events,robotics,intelligent agents,neuromorphic computing,neuromorphic bioelectronics,neuroscience,and other applications,and prospects of this technology. 展开更多
关键词 Resistive switching mechanisms Organic materials Brain-inspired neuromorphic computing NEUROSCIENCE Neuromorphic bioelectronics
在线阅读 下载PDF
Extended π-conjugated systems by external ligand-assisted C-H olefination of heterocycles: Facile access to single-molecular white-light-emitting and NIR fiuorescence materials
6
作者 Ruike Hu Kangmin Wang +4 位作者 Junxiang Liu Jingxian Zhang Guoliang Yang Liqiu Wan Bijin Li 《Chinese Chemical Letters》 2025年第4期131-138,共8页
The design and synthesis of a novel π-conjugated fiuorescent framework by external ligand-assisted C-H olefination of heterocycles with excellent regioselectivity and broad substrate scope are reported herein.These n... The design and synthesis of a novel π-conjugated fiuorescent framework by external ligand-assisted C-H olefination of heterocycles with excellent regioselectivity and broad substrate scope are reported herein.These novel fiuorescent materials could present full-color-tunable emissions with large Stokes shifts. Furthermore, the protocol provides an opportunity to rapidly screen novel organic single-molecule whitelight materials with high fiuorescence quantum yields. The robust organic and low-cost white lightemitting diodes could rapidly be fabricated using the white-light-emitting material. Experimental data and theoretical calculations indicate that in the white-light dual emission the relatively short wavelength from high-lying singlet state emission and the relatively long wavelength from low-lying singlet state emission. The anti-Kasha dual-emission systems will provide a foundation for the development and application of organic single-molecule white light materials, effectively promoting the development and innovation of luminescent materials. In addition, this method demonstrated its potential application in the synthesis of new near-infrared(NIR) fiuorescence materials with large Stokes shifts based on the olefination of heterocycles. 展开更多
关键词 π-Conjugated fiuorescent framework C—H olefination Organic single-molecule white-light materials HETEROCYCLES NIR fiuorescence materials
原文传递
Decomposition of Different Organic Materials and Variation of Active Organic Carbon and Nitrogen Contents in Tobacco-planted Soil 被引量:4
7
作者 鲁耀 郑波 +4 位作者 段宗颜 李祖红 解燕 邱学礼 王建新 《Agricultural Science & Technology》 CAS 2015年第1期107-111,共5页
The oilseed cake, vetch, rapeseed straw, wheat straw and corn straw were buried in tobacco-planted soil. The decomposition rates, the variation of active organic C and N contents in the residues and the relationship b... The oilseed cake, vetch, rapeseed straw, wheat straw and corn straw were buried in tobacco-planted soil. The decomposition rates, the variation of active organic C and N contents in the residues and the relationship between active organic C and N contents and decomposition rate were investigated. The results showed the decomposition rates of different organic materials were all high in the early period and then low in the late period. Among the organic materials, the decomposition rates ranked as oilseed cake 〉 vetch 〉 wheat straw and rapeseed straw 〉 corn straw. The decomposition rate was positively related to total N content (P〈0.01), but was negatively related to the active organic C/N ratio (P〈0.01). However, there was no significant relationship between decomposition ratio and active organic C content. With the proceeding of decomposition, the active organic C content and the total N content in rapeseed straw, vetch, wheat straw and corn straw all trended to increase, but the active organic C/N ratio trended to decrease. However, the variation of active organic C content, total N content and active organic C/N ratio in oilseed cake was on the contrary. 展开更多
关键词 Organic material Decomposition rate Active organic C C/N ratio
在线阅读 下载PDF
Effects of Combined Application of Water Retaining Agents and Organic Materials on Water Holding Characteristics of Yellow Brown Soils in Hilly Areas 被引量:1
8
作者 唐玉邦 虞利俊 +4 位作者 徐磊 罗佳 王东升 范如芹 裴勤 《Agricultural Science & Technology》 CAS 2015年第9期1985-1988,共4页
[Objective] The aim was to reduce fertilizer and water losses caused by surface runoffs in rainy season and provide scientific references for soil moisture in arid season. [Method] The application proportion of comple... [Objective] The aim was to reduce fertilizer and water losses caused by surface runoffs in rainy season and provide scientific references for soil moisture in arid season. [Method] The application proportion of complex water-holding organic materials was determined by multi-factor mixture experiment and the curve changes of soil moisture characters were tested to analyze water-holding capacity and water availability of soils. [Result] The initial moisture content of soil with different mixture proportions improved in varying degrees. For example, when water-retention agents reached 0.4% and 0.6% of soil weight, soil moisture contents were 69.0% and70.5%, respectively, which showed significant differences with the control(S0.0). Soil dehydration terms in different treatments all extended, prolonging in the range of4.6-14 d. [Conclusion] The applications of water-retention agent and organic material would improve water-holding capacity of hills and low mountains, and initial moisture content and dehydration cycle tend to be volatile upon mixture proportion. Therefore,it is necessary to adjust soil fertility, crop species, and irrigation to meet crop demands on fertilizer and water. 展开更多
关键词 Water retaining agents Organic materials Soils of hilly areas Water characteristics
在线阅读 下载PDF
Application of New Slope Greening Technology——Reinforced Organic-Material and Plant Seeds Spraying 被引量:1
9
作者 李国庆 阴磊 吴云天 《Agricultural Science & Technology》 CAS 2014年第1期152-154,共3页
The research introduced the flowchart of organic-material and plant seeds spraying and a case of &quot;Dasi&quot; Highway, the highway from Daxing to Sinan in Guizhou Province, a part of a National Highway from Hang... The research introduced the flowchart of organic-material and plant seeds spraying and a case of &quot;Dasi&quot; Highway, the highway from Daxing to Sinan in Guizhou Province, a part of a National Highway from Hangzhou to Ruili, cal ed Hangrui Highway, slope protection. The flowchart included slope cleaning, net preparation, anchor fixation, adding vegetation-growth plate, spraying organic materi-als, coverage of non-woven fabrics, and maintenance. The technique is proved much efficient in protecting and greening road sideslopes consisting of weathered rocks or hard rocks, which provides a solution for abrupt slope greening technology. 展开更多
关键词 SLOPE GREENING Organic materials Reinforced and plant seeds spraying
在线阅读 下载PDF
Transforming Mesoporous Covalent Organic Polymers into Efficient 18-Electron-Redox Anodes via Redox Site Engineering for Superior Li-Ion Storage
10
作者 Fujie Liu Yaozheng Pan +5 位作者 Jicheng Cai Linfeng Zhong Yi Lin Fan Yang Cong Liu Dingshan Yu 《Energy & Environmental Materials》 2026年第1期46-53,共8页
Redox-active covalent organic polymers(COPs)have emerged as appealing renewable electrode materials for next-generation Li-ion batteries,but their performance is limited by insufficient redox sites and inadequate Li-i... Redox-active covalent organic polymers(COPs)have emerged as appealing renewable electrode materials for next-generation Li-ion batteries,but their performance is limited by insufficient redox sites and inadequate Li-ion diffusion.Here,we develop a novel class of mesoporous covalent organic polymer(namely TF-Azo-COP)bearing multiple redox sites and explore its first use as efficient 18-electron-redox anodes for superior Li-ion storage in both coin-type and fiber-type batteries.The newly produced TF-Azo-COP involves three types of active sites including C=N in triazines and imines,N=N in azo,and C6-ring aromatics to enable 18-Li-ion storage on one repeatable segment,while affording extendedπ-conjugation for fast electron transfer and a pore size of~2.5 nm for facilitated ion diffusion with a high coefficient up to~10^(-10)cm^(2)s^(-1)—superior to some reported organic electrodes.Meriting from the above,pairing TF-Azo-COP with metal Li endows a coin cell with good cycling stability and a large reversible capacity of 795.4 mAh g^(-1)at 0.1 A g^(-1)—representing one of the best performances among reported organic electrodes.When coupled with fiber-shaped LiFePO_(4)cathodes,the assembled fiber cell delivers an excellent combination of linear capacity(0.23 mAh cm^(-1)),energy density(0.55 mWh cm^(-1)),cycling stability(250 cycles),and good flexibility. 展开更多
关键词 covalent organic polymers fiber batteries Li-ion batteries multiple redox chemistry organic electrode materials
在线阅读 下载PDF
Developments of photocatalytic overall water splitting to produce H_(2)
11
作者 Jiaxin Su Jiaqi Zhang +3 位作者 Shuming Chai Masakazu Anpo Yuanxing Fang Xinchen Wang 《Nano Materials Science》 2026年第2期351-363,共13页
Over the past half-century,significant efforts have been dedicated to the photocatalytic H_(2)production from H_(2)O under UV–visible light irradiation.These endeavors have yielded remarkable results,with efficiency ... Over the past half-century,significant efforts have been dedicated to the photocatalytic H_(2)production from H_(2)O under UV–visible light irradiation.These endeavors have yielded remarkable results,with efficiency levels now approaching near 100%apparent quantum yields,notably utilizing inorganic semiconducting materials such as modified Al-doped SrTiO_(3)photocatalysts.Meanwhile,advancements in organic polymer semiconducting materials,exemplified by g-C_(3)N_(4),have led to substantial improvements in the efficiency of photocatalytic overall water splitting for H_(2)evolution reaction.These improvements,achieved through chemical engineering methods and molecular-level modifications,have resulted in an apparent quantum yield of 69%at 405 nm,accompanied by significant red-shifting of optical absorption to 1400 nm.These developments are presented in chronological order over the past half-century,underscoring the ongoing quest for innovative breakthroughs to enable largescale practical applications of solar hydrogen production.Key considerations in this pursuit include efficiency,stability,cost-effectiveness,and the independent evolution of H_(2)and O_(2). 展开更多
关键词 Photocatalytic hydrogen production Inorganic semiconducting material Organic polymer semiconducting material TiO_(2) TITANATE g-C_(3)N_(4)
在线阅读 下载PDF
Aggregate stability and associated C and N in a silty loam soil as affected by organic material inputs 被引量:12
12
作者 LONG Pan SUI Peng +6 位作者 GAO Wang-sheng WANG Bin-bin HUANG Jian-xiong YAN Peng ZOU Juan-xiu YAN Ling-ling CHEN Yuan-quan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第4期774-787,共14页
To make recycling utilization of organic materials produced in various agricultural systems, five kinds of organic materials were applied in a field test, including crop straw (CS), biogas residue (BR), mushroom r... To make recycling utilization of organic materials produced in various agricultural systems, five kinds of organic materials were applied in a field test, including crop straw (CS), biogas residue (BR), mushroom residue (MR), wine residue (WR), pig manure (PM), with a mineral fertilizer (CF) and a no-fertilizer (CK) treatment as a control. Our objectives were: i) to quantify the effects of organic materials on soil C and N accumulation; ii) to evaluate the effects of organic materials on soil aggregate stability, along with the total organic carbon (TOC), and N in different aggregate fractions; and iii) to assess the relationships among the organic material components, soil C and N, and C, N in aggregate fractions. The trial was conducted in Wuqiao County, Hebei Province, China. The organic materials were incorporated at an equal rate of C, and combined with a mineral fertilizer in amounts of 150 kg N ha^-1, 26 kg P ha^-1 and 124 kg K ha-1 respectively during each crop season of a wheat-maize rotation system. The inputted C quantity of each organic material treatment was equivalent to the total amount of C contained in the crop straw harvested in CS treatement in the previous season. TOC, N, water-stable aggregates, and aggregate-associated TOC and N were investigated. The results showed that organic material incorporation increased soil aggregation and stabilization. On average, the soil macroaggregate proportion increased by 14%, the microaggregate proportion increased by 3%, and mean-weight diameter (MWD) increased by 20%. TOC content followed the order of PM〉WR〉MR〉BR〉CS〉CK〉CF; N content followed the order WR〉PM〉MR〉BR〉CS〉CF〉CK. No significant correlation was found between TOC, N, and the quality of organic material. Soil silt and clay particles contained the largest part of TOC, whereas the small macroaggregate fraction was the most sensitive to organic materials. Our results indicate that PM and WR exerted better effects on soil C and N accumulation, followed by MR and BR, suggesting that organic materials from ex situ farmland could promote soil quality more as compared to straw returned in situ. 展开更多
关键词 organic materials AGGREGATES soil organic carbon soil nitrogen STABILIZATION
在线阅读 下载PDF
Recent advances in photofunctional polymorphs of molecular materials 被引量:10
13
作者 Bo Lu Shuya Liu Dongpeng Yan 《Chinese Chemical Letters》 SCIE CAS CSCD 2019年第11期1908-1922,共15页
Recently,molecule-based luminescent materials have been drawing extensive attention due to their desirable properties and promising applications in the fields of sensors,lighting display and cell imaging.Crystalline p... Recently,molecule-based luminescent materials have been drawing extensive attention due to their desirable properties and promising applications in the fields of sensors,lighting display and cell imaging.Crystalline polymorph is an intriguing phenomenon that the presence of multiple packing and aggregate architectures of the same molecular system.The studies on polymorphs for molecule-based fluorophores provide the opportunities to adjust the mode of molecular packing and photophysical properties,which will help to illustrate the structure-property relationship.In this review,we focus on the recent progress in various feasible methods of molecule-based crystalline polymorphism growth and their adjustable photofunctional properties,which will open up possibilities of variant optical applications.Firstly,several effective ways to prepare and screen polymorphs are sorted out.And then,we discuss the discrepant properties and multifunctional applications(such as sensors,laser and OFET).Finally,the development trends and future prospects of these polymorphs are also briefly introduced. 展开更多
关键词 POLYMORPHS Organic molecular materials LUMINESCENCE CRYSTALLINE PREPARATION Optical applications Structure-property relationship
原文传递
Decomposition characteristics of organic materials and their effects on labile and recalcitrant organic carbon fractions in a semi-arid soil under plastic mulch and drip irrigation 被引量:10
14
作者 hu juan wu jinggui qu xiaojing 《Journal of Arid Land》 SCIE CSCD 2018年第1期115-128,共14页
Labile organic carbon (LC) and recalcitrant organic carbon (RC) are two major fractions of soil organic carbon (SOC) and play a critical role in organic carbon turnover and sequestration. The aims of this study ... Labile organic carbon (LC) and recalcitrant organic carbon (RC) are two major fractions of soil organic carbon (SOC) and play a critical role in organic carbon turnover and sequestration. The aims of this study were to evaluate the variations of LC and RC in a semi-arid soil (Inner Mongolia, China) under plastic mulch and drip irrigation after the application of organic materials (OMs), and to explore the effects of OMs from various sources on LC and RC by probing the decomposition characteristics of OMs using in-situ nylon mesh bags burying method. The field experiment included seven treatments, i.e., chicken manure (CM), sheep manure (SM), mushroom residue (MR), maize straw (MS), fodder grass (FG), tree leaves (TL) and no OMs as a control (CK). Soil LC and RC were separated by Huygens D's method (particle size-density), and the average soil mass recovery rate and carbon recovery rate were above 95%, which indicated this method was suitable for carbon pools size analysis. The LC and RC contents significantly (P〈0.01) increased after the application of OMs. Moreover, LC and RC contents were 3.2%-8.6% and 5.0%-9.4% higher in 2016 than in 2015. The applications of CM and SM significantly increased (P〈0,01) LC content and LC/SOC ratio, whereas they were the lowest after the application of TL. However, SOC and RC contents were significantly higher (P〈0.01) after the applications of TL and MS. The correlation analysis indicated the decomposition rate of OMs was positively related with LC content and LC/SOC ratio. In addition, lignin, polyphenol, WOM (total water-soluble organic matter), WHA (water-soluble humic acid), HSL (humicdike substance) and HAL (humic acid-like) contents in initial OMs played important roles in SOC and RC. In-situ nylon mesh bags burying experiment indicated the decomposition rates of CM, SM and MS were significantly higher than those of MR, FG, and TL. Furthermore, MS could result in more lignin derivatives, WHA, and HAL polymers in shorter time during the decomposition process. In conclusion, the application of MS in the semi-arid soil under a long-term plastic mulch and drip irrigation condition could not only improve soil fertility, but also enhance soil carbon sequestration. 展开更多
关键词 organic materials labile organic carbon recalcitrant organic carbon decomposition characteristics plasticmulch drip irrigation Inner Mongolia
在线阅读 下载PDF
Selective extraction and separation of Fe,Mn oxides and organic materials in river surficial sediments 被引量:6
15
作者 LI Feng-mei WANG Xiao-li +2 位作者 LI Yu GUO Shu-hai ZHONG Ai-ping 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2006年第6期1233-1240,共8页
In order to investigate the adsorption mechanism of trace metals to surficial sediments (SSs), a selective extraction procedure was improved in the present work. The selective extraction procedure has been proved to... In order to investigate the adsorption mechanism of trace metals to surficial sediments (SSs), a selective extraction procedure was improved in the present work. The selective extraction procedure has been proved to selectively remove and separate Fe, Mn oxides and organic materials (OMs) in the non-residual fraction from the SSs collected in Songhua River, China. After screening different kinds of conventional extractants of Fe and Mn oxides and OMs used for separation of heavy metals in the soils and sediments, NH2OH .HCl (0.1 mol/L) + HNO3 (0.1 mol/L), (NH4)2C2O4 (0.2 mol/L) + H2C2O4 (pH 3.0), and 30% of H2O2 were respectively applied to selectively extract Mn oxides, Fe/Mn oxides and OMs. After the extraction treatments, the target components were removed with extraction efficiencies between 86.09%--3.36% for the hydroxylamine hydrochloride treatment, 80.63%- 101.09% for the oxalate solution extraction, and 94.76%-102.83% for the hydrogen peroxide digestion, respectively. The results indicate that this selective extraction technology was effective for the extraction and separation ofFe, Mn oxides and OMs in the SSs, and important for further mechanism study of trace metal adsorption onto SSs. 展开更多
关键词 surficial sediments selective extraction iron oxides manganese oxides organic materials
在线阅读 下载PDF
Adsorption of Cu(Ⅱ) on humic acids derived from different organic materials 被引量:6
16
作者 LI Cui-lan JI Fan +6 位作者 WANG Shuai ZHANG Jin-jing GAO Qiang WU Jing-gui ZHAO Lan-po WANG Li-chun ZHENG Li-rong 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第1期168-177,共10页
The adsorption of Cu(Ⅱ) from aqueous solution onto humic acid (HA) which was isolated from cattle manure (CHA), peat (PHA), and leaf litter (LHA) as a function of contact time, pH, ion strength, and initial... The adsorption of Cu(Ⅱ) from aqueous solution onto humic acid (HA) which was isolated from cattle manure (CHA), peat (PHA), and leaf litter (LHA) as a function of contact time, pH, ion strength, and initial concentration was studied using the batch method. X-ray absorption spectroscopy (XAS) was used to examine the coordination environment of the Cu(ll) adsorbed by HA at a molecular level. Moreover, the chemical compositions of the isolated HA were characterized by elemental analysis and solid-state 13C nuclear magnetic resonance spectroscopy (NMR). The kinetic data showed that the adsorption equilibrium can be achieved within 8 h. The adsorption kinetics followed the pseudo-second-order equation. The adsorption isotherms could be well fitted by the Langmuir model, and the maximum adsorption capacities of Cu(ll) on CHA, PHA, and LHA were 229.4,210.4, and 197.7 mg g-1, respectively. The adsorption of Cu(Ⅱ) on HA increased with the increase in pH from 2 to 7, and maintained a high level at pH〉7. The adsorption of Cu(Ⅱ) was also strongly influenced by the low ionic strength of 0.01 to 0.2 mol L-1 NaNO3, but was weakly influenced by high ionic strength of 0.4 to 1 mol L-1 NaNO3. The Cu(Ⅱ) adsorption on HA may be mainly attributed to ion exchange and surface complexation. XAS results revealed that the binding site and oxidation state of Cu adsorbed on HA surface did not change at the initial Cu(Ⅱ) concentrations of 15 to 40 mg L 1. For all the Cu(Ⅱ) adsorption samples, each Cu atom was surrounded by 40/N atoms at a bond distance of 1.95 A in the first coordination shell. The presence of the higher Cu coordination shells proved that Cu(Ⅱ) was adsorbed via an inner-sphere covalent bond onto the HA surface. Among the three HA samples, the adsorption capacity and affinity of CHA for Cu(Ⅱ) was the greatest, followed by that of PHA and LHA. All the three HA samples exhibited similar types of elemental and functional groups, but different contents of elemental and functional groups. CHA contained larger proportions of methoxyl C, phenolic C and carbonyl C, and smaller proportions of alkyl C and carbohydrate C than PHA and LHA. The structural differences of the three HA samples are responsible for their distinct adsorption capacity and affinity toward Cu(Ⅱ). These results are important to achieve better understanding of the behavior of Cu(Ⅱ) in soil and water bodies in the presence of organic materials. 展开更多
关键词 humic acid Cu(Ⅱ) ADSORPTION organic material 13C NMR XAS
在线阅读 下载PDF
Recent progress in organic redox flow batteries:Active materials,electrolytes and membranes 被引量:6
17
作者 Hongning Chen Guangtao Cong Yi-Chun Lu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2018年第5期1304-1325,共22页
Redox flow batteries (RFBs) have great potentials in the future applications of both large scale energy storage and powering the electrical vehicle. Critical challenges including low volumetric energy density. high ... Redox flow batteries (RFBs) have great potentials in the future applications of both large scale energy storage and powering the electrical vehicle. Critical challenges including low volumetric energy density. high cost and maintenance greatly impede the wide application of conventional RFBs based on inorganic materials. Redox-active organic molecules have shown promising prospect in the application of RFBs, benefited from their low cost, vast abundance, and high tunability of both potential and solubility. In this review, we discuss the advantages of redo~ active organic materials over their inorganic compart and the recent progress of organic based aqueous and non-aqueous RFBs. Design considerations in active materi- als, choice of electrolytes and membrane selection in both aqueous and non-aqueous RFBs are discussed. Finally. we discuss remaining critical challenges and suggest future directions for improving organic based RFBs. 展开更多
关键词 Organic materials ELECTROLYTE MembraneFlow battery Low cost
在线阅读 下载PDF
Effect of Organic Materials on Speciation of Copper inSoil Solution 被引量:6
18
作者 WANG GUO CHEN JIANBIN +1 位作者 GU XUNGANG GAO SHAN and CAI HAIYANG(Department of Land and Environmental Science, Fujian Agricultural University, Fuzhou 350002 (Chica)) 《Pedosphere》 SCIE CAS CSCD 1999年第2期139-146,共8页
Incubation of two soils, a red soil derived from granodiorte and a fluvo-aquic soil from alluvial deposit,with rice straw, Chinese milk vetch and pig manure under submerged condition were conducted to study thespecies... Incubation of two soils, a red soil derived from granodiorte and a fluvo-aquic soil from alluvial deposit,with rice straw, Chinese milk vetch and pig manure under submerged condition were conducted to study thespecies of Cu in soil solutions as affected by the organic materials. The organic materials increased totalsoluble Cu by raising dissolved organic carbon (DOC) in soil solution when the solution pH values were belowthe range in which Cu deposited quickly. When the solution pH rose to this range, the increase of DOCdid not raise total soluble Cu. Total soluble Cu in all the treatments dropped with incubation time. Afteradding organic materials labile Cu dropped with incubation time and decreased sharply in the pH range ofCu precipitation. Addition of organic materials enhanced slowly labile Cu but depressed the ratio of labileCu to total soluble Cu. Slowly labile Cu decreased with incubation time. Stepwise multiple linear regressionanalysis showed that total soluble Cu was positively correlated with Eh and DOC (P=0.0025), labile Cuwas negatively correlated with pH (P=0.011 8), and slowly labile Cu was positively correlated with Eh andDOC (P=0.002 2). Both the labile and slowly labile Cu were correlated with total soluble Cu at extremelysignificant levels. 展开更多
关键词 coppert dissolved organic carbon organic material SPECIATION
在线阅读 下载PDF
Room-temperature phosphorescence from purely organic materials 被引量:4
19
作者 Yang Liu Ge Zhan +2 位作者 Zhi-Wei Liu Zu-Qiang Bian Chun-Hui Huang 《Chinese Chemical Letters》 SCIE CAS CSCD 2016年第8期1231-1240,1467,共10页
Room-temperature phosphorescence(RTP) materials have attracted great attention due to their involvement of excited triplet states and comparatively long decay lifetimes.In this short review,recent progress on enhanc... Room-temperature phosphorescence(RTP) materials have attracted great attention due to their involvement of excited triplet states and comparatively long decay lifetimes.In this short review,recent progress on enhancement of RTP from purely organic materials is summarized.According to the mechanism of phosphorescence emission,two principles are discussed to construct efficient RTP materials:one is promoting intersystem crossing(ISC) efficiency by using aromatic carbonyl,heavyatom,or/and heterocycle/heteroatom containing compounds;the other is suppressing intramolecular motion and intermolecular collision which can quench excited triplet states,including embedding phosphors into polymers and packing them tightly in crystals.With aforementioned strategies,RTP from purely organic materials was achieved both in fluid and rigid media. 展开更多
关键词 Room-temperature phosphorescence Purely organic material Intersystem crossing Non-radiation transition
原文传递
上一页 1 2 12 下一页 到第
使用帮助 返回顶部