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Characterization of humic substances in bio-treated municipal solid waste landfill leachate

Guangxia QI, Dongbei YUE, Yongfeng NIE

《环境科学与工程前沿（英文）》 2012年 第6卷 第5期   页码 711-716 doi: 10.1007/s11783-012-0421-z

摘要： Considerable organic matter remains in municipal solid waste landfill leachate after biological treatments. Humic substances (HSs) dominate the organic matter in bio-treated landfill leachate. In this study, the HSs from landfill leachate treated by membrane bioreactor (MBR-HSs) were analyzed via elemental analysis, ultraviolet-visible spectroscopy, Fourier transform infrared spectroscopy, and charge polarized magic-angle spinning- C-nuclear magnetic resonance. The characteristic absorption in the UV wavelength range indicated the presence of high C=C and C=O double bonds within the MBR-HSs. Compared with commercial HSs, MBR-HSs had lower carbon content [48.14% for fulvic acids (FA) and 49.52% for humic acids (HA)], higher nitrogen content (4.31% for FA and 6.16% for HA), lower aromatic structure content, and higher carbohydrate and carboxylic atoms of carbon content. FA predominantly had an aliphatic structure, and HA had less condensed or substituted aromatic ring structures than natural HA. The aromatic carbon content of MBR-HSs was lower than that of humus-derived HSs but higher than that of waste-derived HSs, indicating that MBR-HSs appeared to be more similar to humus-derived HSs than waste-derived HA.

关键词： bio-treated landfill leachate     humic substances     elemental analysis     spectroscopic characteristics    

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V-shaped substrate for surface and volume enhanced Raman spectroscopic analysis of microplastics

《环境科学与工程前沿（英文）》 2022年 第16卷 第11期 doi: 10.1007/s11783-022-1578-8

摘要：

● V-shaped substrate was obtained for SERS analysis of microplastics (diameter ≈ 1 μm).

关键词： SERS     V-shaped     AAO     Microplastic     Atmospheric aerosol    

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fulvic acids during thermal sludge treatment assessed by size fractionation, elementary analysis, and spectroscopic

Yuning YANG,Huan LI,Jinyi LI

《环境科学与工程前沿（英文）》 2014年 第8卷 第6期   页码 854-862 doi: 10.1007/s11783-014-0755-9

摘要： Thermal pretreatment can be applied to sludge anaerobic digestion or dewatering. To analyze the variation in humic substances during thermal sludge treatment, sludge humic and fulvic acids were extracted before and after 30-min thermal treatment at 180°C, and then their contents, molecular weight distributions, elementary compositions, and spectral characteristics were compared. The results showed that the total contents of humic and fulvic acids in the sludge almost remained constant during thermal treatment, but 35% of humic and fulvic acids were dissolved from the sludge solids. Moreover, both humic and fulvic acids were partly decomposed and 32% of humic acids were converted to fulvic acids. The median value of the molecular weights of humic acids decreased from 81 to 41 kDa and that of fulvic acids decreased from 15 to 2 kDa. Besides the reduction in molecular size, the chemical structures of humic and fulvic acids also exhibited a slight change, i.e. some oxygen functional groups disappeared and aromatic structures increased after thermal sludge treatment.

关键词： sludge     thermal treatment     humic acids     fulvic acids    

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Diporphyrin tweezer for multichannel spectroscopic analysis of enantiomeric excess

Daniel T. Payne, Mandeep K. Chahal, Václav Březina, Whitney A. Webre, Katsuhiko Ariga, Francis D’Souza, Jan Labuta, Jonathan P. Hill

《化学科学与工程前沿（英文）》 2020年 第14卷 第1期   页码 28-40 doi: 10.1007/s11705-019-1869-1

摘要： Chiral 1,1’-binaphthyl-linked diporphyrin ‘tweezers’ ( )- /( )- and the corresponding zinc(II) complexes ( )- /( )- were prepared as chiral host molecules, and their utility for chiral analyses (especially enantiomeric excess ( ) determinations) were evaluated. Tris(1- -dodecyl)porphyrins were used for the first time as the interacting units. Host capabilities of the diporphyrin tweezers were investigated by titrations with ( , )- and ( , )-cyclohexane-1,2-diamine (CHDA). The host molecules could be used as multichannel probes of by using UV-vis, circular dichroism (CD), fluorescence emission and H nuclear magnetic resonance ( H-NMR) methods. Chiral configurations could also be differentiated using CD or H-NMR spectroscopy. All three optical techniques give good resolution of with reasonable sensitivity considering the low concentrations used (ca. 10 mol·L ). The determination of CHDA enantiomers using NMR spectroscopy is also possible because of the reasonably well separated resonances in the case of ( , )- and ( , )-CHDA. Non-metallated ( )- /( )- hosts could not be used to detect chiral information in a strongly acidic chiral guest. This work demonstrates the utility of 1,1’-binapthyl-linked chiral hosts for chiral analysis of ditopically interacting enantiomers.

关键词： porphyrin dimer     chirality     enantiomeric excess     CD     fluorescence    

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Synthesis, spectroscopic, and electrochemical properties of two dyads consisted of tetrathiafulvalene

Guoqiao LAI, Yibo LIU, Meijiang LI, Yongjia SHEN

《化学科学与工程前沿（英文）》 2009年 第3卷 第2期   页码 192-195 doi: 10.1007/s11705-009-0015-x

摘要： Two donor-σ-acceptor molecules containing tetrathiafulvalene (TTF) and carbazole moieties were synthesized by the reaction of 9-(4-bromo-butyl)-carbazole ( ) with 2,6-bis(hexylthio)-3-(2-cyanoethylthio)-7-(methylthio)-tetrathiafulvalene ( ) or 2,6-bis(2-cyanoethylthio)-3,7-bis(methylthio)tetrathiafulvalene ( ) in the presence of CsOH·H O, respectively. The structures of the molecules were characterized by H NMR, C NMR, MS, and elemental analyses. They showed negligible intramolecular charge-transfer interaction in their ground states as indicated by their UV-Vis spectroscopics and cyclic voltammetry results. Compared with carbazole, their fluorescence was strongly quenched, which implied that a photo induced electron transfer (PET) interaction between TTF and carbazole moieties occurred.

关键词： donor-σ-acceptor molecule     intramolecular charge transfer interaction     photo induced electron transfer     tetrathiafulvalene     carbazole    

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Fluorescence spectroscopic studies of the effect of granular activated carbon adsorption on structural

Shuang XUE, Qingliang ZHAO, Liangliang WEI, Xiujuan HUI, Xiping MA, Yingzi LIN

《环境科学与工程前沿（英文）》 2012年 第6卷 第6期   页码 784-796 doi: 10.1007/s11783-012-0436-5

摘要： This work investigated the effect of granular activated carbon adsorption (GACA) on fluorescence characteristics of dissolved organic matter (DOM) in secondary effluent, by means of excitation–emission matrix (EEM) spectra, the fluorescence regional integration (FRI) method, synchronous spectra, the fluorescence index defined as the ratio of fluorescence emission intensity at wavelength 450 nm to that at 500 nm at excitation ( )=370 nm, and the wavelength that corresponds to the position of the normalized emission band at its half intensity ( ). DOM in the secondary effluent from the North Wastewater Treatment Plant (Shenyang, China) was fractionated using XAD resins into 5 fractions: hydrophobic acid (HPO–A), hydrophobic neutral (HPO–N), transphilic acid (TPI–A), transphilic neutral (TPI–N) and hydrophilic fraction (HPI). Results showed that fluorescent materials in HPO–N and TPI–N were less readily removed than those in the other fractions by GACA. The relative content of fluorescent materials in HPO–A, TPI–A and HPI decreased whereas that in HPO–N and TPI–N increased as a consequence of GACA. Polycyclic aromatics in all DOM fractions were preferentially absorbed by GACA, in comparison with bulk DOM expressed as DOC. On the other hand, the adsorption of aromatic amino acids and humic acid-like fluorophores exhibiting fluorescence peaks in synchronous spectra by GACA seemed to be dependent on the acid/neutral properties of DOM fractions. All five fractions had decreased fluorescence indices as a result of GACA. GACA led to a decreased value for HPO–A, increased values for HPO–N, TPI–A and HPI, and a consistent value for TPI–N.

关键词： granular activated carbon adsorption     dissolved organic matter     fractionation     fluorescence    

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Recent progress in hydrodynamic characteristics research and application of annular centrifugal extractors

《化学科学与工程前沿（英文）》 2022年 第16卷 第6期   页码 854-873 doi: 10.1007/s11705-022-2156-0

摘要： The annular centrifugal extractor (ACE) integrates mixing and separation. It has been widely used in many industrial fields because of its low residence time, compact structure, and high mass transfer efficiency. Most of the literature has focused on flow instabilities, flow visualization, and computational fluid dynamics simulations. More recently, research on hydrodynamic behavior and structural optimization has received widespread attention. With the development of ACE technology, applications have been broadened into several new areas. Hence, this paper reviews research progress regarding ACE in terms of hydrodynamic characteristics and the structural improvements. The latest applications covering hydrometallurgy, nuclear fuel reprocessing, bio-extraction, catalytic reaction, and wastewater treatment are presented. We also evaluate future work in droplet breakup and coalescence mechanisms, structural improvements specific to different process requirements, scaling-up methods, and stability and reliability after scaling-up.

关键词： annular centrifugal extractor     hydrodynamic characteristics     structure optimization     the latest application    

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Clinical characteristics and outcomes of biopsy-proven diabetic nephropathy

null

《医学前沿（英文）》 2017年 第11卷 第3期   页码 386-392 doi: 10.1007/s11684-017-0574-z

摘要：

Kidney damage is common in patients with diabetes mellitus (DM). However, whether the type of kidney damage can be reliably diagnosed using clinical data alone remains unclear. Predictive factors for diabetic nephropathy (DN) outcomes are also poorly understood. In this study, the clinical manifestations of 111 cases of biopsy-proven DN were described, and the clinical and pathological parameters of patients with different DN outcomes were compared. Results showed that long DM duration (>10 years in 32.4% of patients), severe proteinuria (62.2%), and renal dysfunction (estimated glomerular filtration rate [eGFR]<60 mL/(min·1.73 m2)) (52.3%) did not accurately indicate whether the condition of these patients progressed to DN. Hematuria (48.6%) failed to specify either DN or nondiabetic renal disease. Diabetic retinopathy (78.4%) was a crucial complication in patients with DN. Kaplan–Meier analysis revealed that the renal survival of 53 patients who were diagnosed with DN and were followed up was not significantly associated with glomerular classification (P>0.05). Cox’s regression analysis demonstrated that renal survival time was significantly influenced by sex (b= 1.394, P= 0.038), hematuria (b= 0.036, P= 0.029), and eGFR (b= −0.039, P= 0.002) but was not significantly affected by age, 24 h urinary protein excretion, or glomerular classification (P>0.05). In conclusion, the clinical characteristics of DN vary, and renal biopsy is necessary to determine renal damage patterns. Sex, hematuria, and the eGFR may affect DN outcomes, whereas the glomerular classification may not.

关键词： diabetic nephropathy     clinical characteristics     renal biopsy     outcomes    

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Obesity in China: its characteristics, diagnostic criteria, and implications

null

《医学前沿（英文）》 2015年 第9卷 第2期   页码 129-133 doi: 10.1007/s11684-015-0387-x

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从天然产物创制新药的发展趋势

于德泉

《中国工程科学》 1999年 第1卷 第2期   页码 87-90

摘要：

文章展望了从天然产物中创制新药的发展趋势。单味中草药有效成分的研究重点将转向瞄准质控的中药复方化学成分研究。进入21世纪，中国天然药物研究要在国际上占有重要位置，突破口便是中药复方现代化，其关键之一便是化学（有效）成分研究。从中草药中发现有效成分或先导物必须采用化学成分与生物活性研究融为一体的机制，采用高通量筛选，目标就是寻找有效成分或先导物进而创制新药。长短结合，正确处理知识创新和新药开发的关系。知识创新须体现在创制新药的应用基础研究中，是产生巨大效益的理论基础；短程开发是知识累积水平的体现，是科研经费的必要补充和保证。改革传统天然产物化学研究模式，实施以当代最先进大型谱仪为先导的天然产物研究战略。

关键词： 天然产物     创制新药     中草药化学成分     波谱技术     高效色谱与质谱联用     高效色谱与核磁共振联用    

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Obesity-related glomerulopathy: pathogenesis, pathologic, clinical characteristics and treatment

null

《医学前沿（英文）》 2017年 第11卷 第3期   页码 340-348 doi: 10.1007/s11684-017-0570-3

摘要：

In light of the rapid increase in the number of obesity incidences worldwide, obesity has become an independent risk factor for chronic kidney disease. Obesity-related glomerulopathy (ORG) is characterized by glomerulomegaly in the presence or absence of focal and segmental glomerulosclerosis lesions. IgM and complement 3 (C3) nonspecifically deposit in lesions without immune-complex-type deposits during ORG immunofluorescence. ORG-associated glomerulomegaly and focal and segmental glomerulosclerosis can superimpose on other renal pathologies. The mechanisms under ORG are complex, especially hemodynamic changes, inflammation, oxidative stress, apoptosis, and reduced functioning nephrons. These mechanisms synergize with obesity to induce end-stage renal disease. A slow increase of subnephrotic proteinuria (<3.5 g/d) is the most common clinical manifestation of ORG. Several treatment methods for ORG have been developed. Of these methods, renin–angiotensin–aldosterone system blockade and weight loss are proven effective. Targeting mitochondria may offer a novel strategy for ORG therapy. Nevertheless, more research is needed to further understand ORG.

关键词： obesity-related glomerulopathy     pathogenesis     pathologic     clinical characteristics    

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Dynamic characteristics of molten droplets and hot particles falling in liquid pool

Liangxing LI, Weimin MA, Huixiong LI, Tingkuan CHEN,

《能源前沿（英文）》 2010年 第4卷 第2期   页码 246-251 doi: 10.1007/s11708-009-0077-y

摘要： The dynamic characteristics of molten droplets and hot particles at the very beginning of their fall into coolant pools are presented. The falling course of a single droplet or a single hot particle was recorded by a high-speed camera and a curve of velocity . time was obtained. Emphasis was placed on the effects of the droplet’s size and temperature, the coolant’s temperature and properties, and the droplet’s physical properties on the moving behavior. The results for the all cases showed that the velocity of a falling droplet/particle decreased rapidly but rebounded shortly, at the beginning of droplet/particle falling in the coolant. Following such a V-shaped evolution in velocity, the droplet/particle slows down gradually to a comparatively steady velocity. An increase in either coolant temperature or droplet temperature results in a larger velocity variation in the “J-region”, but a smaller deceleration when it moves out of the “J-region”. The elevated volatility of a coolant leads to a steeper deceleration in the “J-region” and beyond. The bigger size of a particle leads to a greater velocity variation in the “J-region” and terminal velocity. A high melting point and thermal conductivity as well as lower heat capacity contribute to dramatic variation in the “J-region” and low terminal velocity.

关键词： dynamic characteristics     molten droplets     high-temperature particles     fuel and coolant interactions    

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Combustion characteristics and kinetics of bio-oil

Ruixia ZHANG, Zhaoping ZHONG, Yaji HUANG

《化学科学与工程前沿（英文）》 2009年 第3卷 第2期   页码 119-124 doi: 10.1007/s11705-009-0068-x

摘要： The combustion characteristics of bio-oils derived from rice husk and corn were studied by thermogravimetry analysis. According to the thermogravimetry (TG), differential thermogravimetry (DTG) and differential thermal analysis (DTA) curves of bio-oils in air and nitrogen atmosphere, we analyzed the combustion characteristics of different kinds of bio-oils in different atmospheres and worked out the combustion kinetics parameters of the bio-oil, providing reliable base data for the burning of bio-oil. The thermogravimetry indicated that the combustion process of bio-oil was divided into three stages. At the same time, the combustion process can be described by different order reaction models, and with the method of Coats-Redfern, the activation energy and frequency factor of different kinds of bio-oils were obtained.

关键词： bio-oil     combustion characteristics     combustion kinetics    

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Study on combustion characteristics of blended coals

LI Yonghua, WANG Chunbo, CHEN Hongwei

《能源前沿（英文）》 2007年 第1卷 第1期   页码 96-100 doi: 10.1007/s11708-007-0010-1

摘要： Power plants in China have to burn blended coal instead of one specific coal for a variety of reasons. So it is of great necessity to investigate the combustion of blended coals. Using a test rig with a capacity of 640 MJ/h with an absolute milling system and flue gas online analysis system, characteristics such as burnout, slag, and pollution of some blended coals were investigated. The ratio of coke and slag as a method of distinguishing coal slagging characteristic was introduced. The results show that the blending of coal has some effect on NO but there is no obvious rule. SO emission can be reduced by blending low sulfur coal.

关键词： combustion     capacity     variety     blended     burnout    

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The strength–dilatancy characteristics embraced in hypoplasticity

Zhongzhi FU, Sihong LIU, Zijian WANG

《结构与土木工程前沿（英文）》 2013年 第7卷 第2期   页码 178-187 doi: 10.1007/s11709-013-0191-0

摘要： The strength-dilatancy characteristics of frictional materials embraced in the hypoplastic model proposed by Gudehus and Bauer are investigated and compared with the revised model suggested by Huang. In the latter the deviatoric stress in the model by Gudehus and Bauer is replaced by a transformed stress according to the stress transformation technique proposed by Matsuoka. The flow rule, the failure state surface equation and the strength-dilatancy relationship embraced in both models are derived analytically. The performance of the two hypoplastic models in reproducing the relationship between the peak strength and the corresponding dilation rate under triaxial compression, plane compression and plane shearing are then extensively investigated and compared with experimental results and with the predictions made by particular classical stress-dilatancy theories. Numerical investigations show that the performance in reproducing the strength-dilatancy relationship is quite satisfactory under triaxial compression stress state in both models and the predictions made by the transformed stress based model are closer to the results obtained from classical stress-dilatancy theories for plane compression and plane shearing problems.

关键词： strength     dilatancy     hypoplasticity     frictional materials    

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标题 作者 时间 类型 操作

Characterization of humic substances in bio-treated municipal solid waste landfill leachate

Guangxia QI, Dongbei YUE, Yongfeng NIE

期刊论文

V-shaped substrate for surface and volume enhanced Raman spectroscopic analysis of microplastics

期刊论文

fulvic acids during thermal sludge treatment assessed by size fractionation, elementary analysis, and spectroscopic

Yuning YANG,Huan LI,Jinyi LI

期刊论文

Diporphyrin tweezer for multichannel spectroscopic analysis of enantiomeric excess

Daniel T. Payne, Mandeep K. Chahal, Václav Březina, Whitney A. Webre, Katsuhiko Ariga, Francis D’Souza, Jan Labuta, Jonathan P. Hill

期刊论文

Synthesis, spectroscopic, and electrochemical properties of two dyads consisted of tetrathiafulvalene

Guoqiao LAI, Yibo LIU, Meijiang LI, Yongjia SHEN

期刊论文

Fluorescence spectroscopic studies of the effect of granular activated carbon adsorption on structural

Shuang XUE, Qingliang ZHAO, Liangliang WEI, Xiujuan HUI, Xiping MA, Yingzi LIN

期刊论文

Recent progress in hydrodynamic characteristics research and application of annular centrifugal extractors

期刊论文

Clinical characteristics and outcomes of biopsy-proven diabetic nephropathy

null

期刊论文

Obesity in China: its characteristics, diagnostic criteria, and implications

null

期刊论文

从天然产物创制新药的发展趋势

于德泉

期刊论文

Obesity-related glomerulopathy: pathogenesis, pathologic, clinical characteristics and treatment

null

期刊论文

Dynamic characteristics of molten droplets and hot particles falling in liquid pool

Liangxing LI, Weimin MA, Huixiong LI, Tingkuan CHEN,

期刊论文

Combustion characteristics and kinetics of bio-oil

Ruixia ZHANG, Zhaoping ZHONG, Yaji HUANG

期刊论文

Study on combustion characteristics of blended coals

LI Yonghua, WANG Chunbo, CHEN Hongwei

期刊论文

The strength–dilatancy characteristics embraced in hypoplasticity

Zhongzhi FU, Sihong LIU, Zijian WANG

期刊论文