In order to effectively cultivate applied pharmaceutical talents,aiming at the current teaching situation of organic chemistry,the basic course of pharmaceutical specialty,including the problems of curriculum setting,...In order to effectively cultivate applied pharmaceutical talents,aiming at the current teaching situation of organic chemistry,the basic course of pharmaceutical specialty,including the problems of curriculum setting,experimental teaching,and the integration of classroom and professional knowledge,it is proposed to overcome the problem of curriculum setting by combining"online+offline"in teaching.It should overcome the problems in experimental teaching with the help of virtual simulation platform.By cultivating students organic chemistry thinking and paying attention to the integration of subject and professional knowledge,students recognition of organic chemistry course can be improved,and the quality of training can be improved.展开更多
The recently introduced even-odd rule has been shown to successfully represent chemical structures of ions and molecules. While comparing available drawings in the scientific literature with the list of compounds pred...The recently introduced even-odd rule has been shown to successfully represent chemical structures of ions and molecules. While comparing available drawings in the scientific literature with the list of compounds predicted by the even-odd rule, it became however obvious that existing compounds are fewer than expected. Several predicted compounds involving many covalent bonds have apparently never been experimentally observed. Neutral oxygen for instance is expected to have 6 valence electrons, whereas oxygen can only build a maximum of two bonds, as in water. This specificity is observed for elements in the top-right corner of the periodic table. For compounds to contain only single covalent bonds, and thus follow the even-odd rule, further explanations are necessary. The present paper proposes that those specific elements experience a transfer of electrons from the valence shell into the inner shell, making them unavailable for further bonding. These elements will be described as organic, hereby providing a clear and hopefully unifying definition of the term. In opposition, inorganic elements have a constant inner shell no matter their electrical state or the number of bonds they maintain. More than 70 compounds involving 11 elements of the main group are studied, revealing a progression from fully inorganic elements at the left of the periodic table to fully organic elements. The transition between inorganic or organic elements is made of few elements that take an organic form when negatively charged;they are labelled semi-organic. The article concludes that the fully organic elements of the main group are Oxygen and Fluorine, whereas semi-organic elements are more numerous: C, N, S, Cl, Se, Br and I. Thus, the even-odd rule becomes fully compatible with scientific knowledge of compounds in liquid or gaseous phase.展开更多
Following the introduction of the new even-odd and isoelectronic rules and definitions affecting the understanding of electronic structure and bonds, the author has thought necessary to summarize understandings in the...Following the introduction of the new even-odd and isoelectronic rules and definitions affecting the understanding of electronic structure and bonds, the author has thought necessary to summarize understandings in the form of a table. The classical periodic table, a simple tool used by generations of physicists, is here extended to become a useful tool aimed specifically at chemists. In chemistry, position and number of covalent bonds of each atom are needed, as well as the exact location of charges. The table gives the number of possible bonds for each element and reveals how it is affected by charges. Additionally, the specific table indicates for each atom its isoelectronic elements and highlights the distinction between organic and inorganic elements. Discussion is led on the first two rows of the table by successfully comparing its statement with more than 50 well-known liquid and gaseous compounds.展开更多
Sodium-ion batteries(SIBs)have attracted considerable interest as an alternative to lithium-ion batteries owing to their similar electrochemical performance and superior long-term cycle stability.Organic materials are...Sodium-ion batteries(SIBs)have attracted considerable interest as an alternative to lithium-ion batteries owing to their similar electrochemical performance and superior long-term cycle stability.Organic materials are regarded as promising anode materials for constructing SIBs with high capacity and good retention.However,utilization of organic materials is rather limited by their low energy density and poor stability at high current densities.To overcome these limitations,we utilized a novel polymeric disodium phthalocyanines(pNaPc)as SIB anodes to provide stable coordination sites for Na ions as well as to enhance the stability at high current density.By varying the linker type during a one-pot cyclization and polymerization process,two pNaPc anodes with O-(O-pNaPc)and S-linkers(S-pNaPc)were prepared,and their structural and electrochemical properties were investigated.The O-pNaPc binds Na ions with a lower binding energy compared with S-pNaPc,which leads to more facile Na-ion coordination/dissociation when engaged as SIB anode.The use of O-pNaPc significantly improves the redox kinetics and cycle stability and allows the fabrication of a full cell against Na_(3)V_(2)(PO_(4))_(2)F_(3)/C cathode,which demonstrates its practical application with high energy density(288 Wh kg^(-1))and high power density(149 W kg^(-1)).展开更多
Previous studies showed that water chemistry and concentrations of dissolved organic matter (DOM) could affect its molecular conformation and binding characteristics with hydrophobic organic contaminants (HOCs). Howev...Previous studies showed that water chemistry and concentrations of dissolved organic matter (DOM) could affect its molecular conformation and binding characteristics with hydrophobic organic contaminants (HOCs). However, the conformational change of DOM resultant from water chemistry and concentrations of DOM was not extensively investigated; therefore, the contradictory reports regarding the binding property with HOCs were available in literature. In this study, the effects of ionic strength, pH and DOM concentrations on the fluorescence properties of two humic acids (HA), namely Fluka HA and Amherst HA, were investigated by three-dimensional excitation-emission matrix fluorescence spectroscopy (3DEEM) and steady-state fluorescence polarization (FP) techniques. The results not only corroborated previous observations obtained by other investigators, but revealed some new information about the fluorescence properties and molecular conformation of the humic acids under different water chemistry and DOM concentration conditions, which could shed light on its binding mechanisms and binding properties with HOCs.展开更多
Overall, General, Organic, and Biological Chemistry is a very useful text to support a twosemester undergraduate course series in chemistry for health sciences students. Its strengths are the use of the P.A.V.E. way t...Overall, General, Organic, and Biological Chemistry is a very useful text to support a twosemester undergraduate course series in chemistry for health sciences students. Its strengths are the use of the P.A.V.E. way to student learning applications. It is very obvious that the author has the background and the preparation of the student taking the course(s) in mind when she was writing the textbook.展开更多
Different imines were prepared.The reaction was carried out using different conditions,with aromatic aldehydes,aniline and with different energy sources.Yield,purity and experimental fusion point were calculated in ea...Different imines were prepared.The reaction was carried out using different conditions,with aromatic aldehydes,aniline and with different energy sources.Yield,purity and experimental fusion point were calculated in each case,and they were compared to the ones found in literature.The importance of structural effects of aldehyde reacting with aniline was established as well as reaction conditions.The efficacy of the reaction can not be predicted,since each aldehyde has a different structure and therefore reacts differently.The main objective of this project is academic.A methodology to carry out a structured research(it is one of the levels of problem-based learning(ABP)),was implemented.Students work in pairs using Combinatorial Chemistry,and each pair does a different exercise on the same theoretical objective.Results from every team are discussed in a seminary where conclusions regarding which was the most efficient reaction are reached.展开更多
Employing cathode materials with multiple redox couples and electrolytes with efficient cation transport kinetics are two effective approaches to improving the electrochemical performance of batteries.In this work,for...Employing cathode materials with multiple redox couples and electrolytes with efficient cation transport kinetics are two effective approaches to improving the electrochemical performance of batteries.In this work,for the first time,we present a design strategy of simultaneously realizing reversible cationic and anionic redox chemistries as well as selective anion/cation transport in the viologen-based COFs(BAVCOF:X,coordinated anions of X=Cl^(-),Br^(-),I^(-),and ClO_(4)^(-))for high-performance Na-ion cathodes.Besides the cationic redox of viologen segments,the different redox activities of anions effectively tune the total capacities of the COFs.Meanwhile,electrochemical analysis and ab-initial molecular dynamics(AIMD)calculation illustrate that the anion/cation transport kinetics of electrolytes caged in the COFs'channels can be selectively tuned by the coordinated anions.As a result,combining high-potential Br-/Br_(2)redox couple,cationic redox of viologen segments,and enhanced Na+transport kinetics,the BAV-COF:Brdemonstrates stable performance with energy densities of 358.7 and 145.2 Wh kg^(-1)at power densities of 116.5 and 2124.1 W kg^(-1),respectively.This study offers new insight into the fabrication of organic cathodes with anionic redox and the advantages of COFs electrode materials in anion/cation transport selectivity for energy storage applications.展开更多
To realistically simulate the impacts of marine isoprene and primary organic aerosols (POA) on atmospheric chemistry, a unified model framework with online emissions, comprehensive treatment of gas-phase chemistry, an...To realistically simulate the impacts of marine isoprene and primary organic aerosols (POA) on atmospheric chemistry, a unified model framework with online emissions, comprehensive treatment of gas-phase chemistry, and advanced aerosol microphysics is required. In this work, the global-through-urban WRF/Chem model (GU-WRF/Chem) implemented with the online emissions of marine isoprene and size-resolved marine POA is applied to examine such impacts. The net effect of these emissions was increased surface concentrations of isoprene and organic aerosols and decreased surfaced concentrations of hydroxyl radical and ozone over most marine regions. With the inclusion of these emissions, GU-WRF/Chem better predicted the surface concentrations of isoprene and organic aerosols and the aerosol number size distribution when compared to measurements in clean marine conditions.展开更多
From the perspective of students,the effectiveness of task-based approach in In-organic and Analytical Chemistry course were summarized.The strength and weak points of TBA were analyzed,and the specific suggestions fo...From the perspective of students,the effectiveness of task-based approach in In-organic and Analytical Chemistry course were summarized.The strength and weak points of TBA were analyzed,and the specific suggestions for obtaining better effect were put forward.The result showed a satisfactory achievement and unexpected result in showing the effectiveness of this teaching model.Not only could this TBA enhance student's overall knowledge of discipline but also cultivate students' multi-dimensional competence:competence in searching literatures, communication and management,autonomous,co-operative and reflective learning,and competence in analyzing and problem-solving,as well as improving their language expression ability,and skills in using multi-media and internet technology into their academic course learning and research.The implication of this research on the classroom teaching practice will shed light on the future teaching reform of other courses in China.展开更多
After a disciplinary upsurge, organic chemistry is about to embark on an epoch-making transition at the turn of the century. At present when the discipline is once again making its way into life sciences, this article...After a disciplinary upsurge, organic chemistry is about to embark on an epoch-making transition at the turn of the century. At present when the discipline is once again making its way into life sciences, this article gives a running commmentary on its current state and some developmental trends making a debut in this new research orientation. Finally, several ideas are aired to the community of Chinese chemists, advising them on how to welcome the historic transition.展开更多
Organic chemistry is undergoing a major paradigm shift,moving from a labor-intensive approach to a new era dominated by automation and artificial intelligence(AI).This transformative shift is being driven by technolog...Organic chemistry is undergoing a major paradigm shift,moving from a labor-intensive approach to a new era dominated by automation and artificial intelligence(AI).This transformative shift is being driven by technological advances,the ever-increasing demand for greater research efficiency and accuracy,and the burgeoning growth of interdisciplinary research.AI models,supported by computational power and algorithms,are drastically reshaping synthetic planning and introducing groundbreaking ways to tackle complex molecular synthesis.In addition,autonomous robotic systems are rapidly accelerating the pace of discovery by performing tedious tasks with unprecedented speed and precision.This article examines the multiple opportunities and challenges presented by this paradigm shift and explores its far-reaching implications.It provides valuable insights into the future trajectory of organic chemistry research,which is increasingly defined by the synergistic interaction of automation and AI.展开更多
The binding constant(KDOM) of pyrene onto different molecular weight(Mw) fractions of a dissolved organic matter(DOM) extract from an estuarine sediment was measured via a fluorescence quenching method,and the p...The binding constant(KDOM) of pyrene onto different molecular weight(Mw) fractions of a dissolved organic matter(DOM) extract from an estuarine sediment was measured via a fluorescence quenching method,and the possible binding mechanisms were discussed.The influence of water chemical parameters on pyrene binding was studied to elucidate the effects of DOM steric conformation.DOM fraction with larger M w(14000) showed a greater KDOM(2.02×10 5) than that with smaller Mw did,and the KDOMs were 1.16×105 and 1.13×105 for the fractions with M w of 1000―14000 and 1000,respectively.The K DOM s of different M w DOM fractions were correlated positively with the atomic ratio of C/H and absorbance at 280 nm;while a negative correlation existed between K DOM and(O+C)/N(atomic ratio),and K DOM and O-containing groups.These correlations indicate the positive influence of aromatic structure and the negative effect of polarity on DOM binding capacity.Infrared spectroscopy revealed that specific interactions existed between pyrene and the DOM fraction with larger M W besides hydrophobic partition,i.e.,NH-π interaction in DOM moiety(1000―14000) and π-π electron donor acceptor(EDA) forces in DOM moiety(14000).KDOM varied in a complex pattern with increasing cation concentration and pH,which could be explained by the change in DOM steric conformation.Formed aggregates favored the lipophilic partition of pyrene.However,the accessibility to some interior binding sites became low when the aggregate was too large,leading to a reduced KDOM.展开更多
OMGKRP is one of various Karuho poison mysteriously used by unscrupulous individuals to kill people during conflict and animals in Goma City, in DRC. The symptoms and signs of most cases are usually confused with many...OMGKRP is one of various Karuho poison mysteriously used by unscrupulous individuals to kill people during conflict and animals in Goma City, in DRC. The symptoms and signs of most cases are usually confused with many chronic diseases like tuberculosis and HIV/AIDS;with renal, hepatic and cardiac manifestations as well as blood chemistry changes. The study investigated the toxic effect of OMGKRP poison on blood chemistry, serum enzymes and organ toxicity including the kidney, lung, liver and heart of Wistar albino rats. A laboratory-based experimental study was conducted. Fifty animals in 5 groups each with 10 animals were dosed daily for 28 days with 1.0 mg, 5.0 mg, 20.0 mg and 5000.0 mg/Kg body weight of OMGKRP and normal saline as control group. International standard guidelines, OECD 407 and NIH 2011 were followed during the study period. The blood chemistry analysis, relative organ weight and histopathological changes in the kidney, lung, liver and heart were performed. The findings showed that OMGKRP was associated with increased blood chemistry parameters including total proteins, creatinine, urea, K+?levels, direct albumin levels, a decrease in Cl−?levels and albumin levels. Histopathological findings showed an increased relative weight and tissue damages of the lung, kidney, liver and heart. Therefore, OMGKRP Karuho poison caused toxicity on blood chemistry, serum enzymes as well as histopathological changes in the lung, renal, hepatic and cardiac tissue damages in Wistar albino rats.展开更多
基金Supported by No.2022-79 Teaching Reform Project of Guangzhou Huashang College(HS2022ZLGC58)No.2022-79 Quality Engineering Project of Guangzhou Huashang College(HS2022ZLGC04).
文摘In order to effectively cultivate applied pharmaceutical talents,aiming at the current teaching situation of organic chemistry,the basic course of pharmaceutical specialty,including the problems of curriculum setting,experimental teaching,and the integration of classroom and professional knowledge,it is proposed to overcome the problem of curriculum setting by combining"online+offline"in teaching.It should overcome the problems in experimental teaching with the help of virtual simulation platform.By cultivating students organic chemistry thinking and paying attention to the integration of subject and professional knowledge,students recognition of organic chemistry course can be improved,and the quality of training can be improved.
文摘The recently introduced even-odd rule has been shown to successfully represent chemical structures of ions and molecules. While comparing available drawings in the scientific literature with the list of compounds predicted by the even-odd rule, it became however obvious that existing compounds are fewer than expected. Several predicted compounds involving many covalent bonds have apparently never been experimentally observed. Neutral oxygen for instance is expected to have 6 valence electrons, whereas oxygen can only build a maximum of two bonds, as in water. This specificity is observed for elements in the top-right corner of the periodic table. For compounds to contain only single covalent bonds, and thus follow the even-odd rule, further explanations are necessary. The present paper proposes that those specific elements experience a transfer of electrons from the valence shell into the inner shell, making them unavailable for further bonding. These elements will be described as organic, hereby providing a clear and hopefully unifying definition of the term. In opposition, inorganic elements have a constant inner shell no matter their electrical state or the number of bonds they maintain. More than 70 compounds involving 11 elements of the main group are studied, revealing a progression from fully inorganic elements at the left of the periodic table to fully organic elements. The transition between inorganic or organic elements is made of few elements that take an organic form when negatively charged;they are labelled semi-organic. The article concludes that the fully organic elements of the main group are Oxygen and Fluorine, whereas semi-organic elements are more numerous: C, N, S, Cl, Se, Br and I. Thus, the even-odd rule becomes fully compatible with scientific knowledge of compounds in liquid or gaseous phase.
文摘Following the introduction of the new even-odd and isoelectronic rules and definitions affecting the understanding of electronic structure and bonds, the author has thought necessary to summarize understandings in the form of a table. The classical periodic table, a simple tool used by generations of physicists, is here extended to become a useful tool aimed specifically at chemists. In chemistry, position and number of covalent bonds of each atom are needed, as well as the exact location of charges. The table gives the number of possible bonds for each element and reveals how it is affected by charges. Additionally, the specific table indicates for each atom its isoelectronic elements and highlights the distinction between organic and inorganic elements. Discussion is led on the first two rows of the table by successfully comparing its statement with more than 50 well-known liquid and gaseous compounds.
基金financial supports from the Research Grants Council of the Hong Kong Special Administrative Region(Poly U15217521)the Hong Kong Polytechnic University(Q-CDA3)Initiative for fostering University of Research and Innovation Program of the National Research Foundation(NRF)funded by the Korean government(MSIT)(No.2020M3H1A1077095)
文摘Sodium-ion batteries(SIBs)have attracted considerable interest as an alternative to lithium-ion batteries owing to their similar electrochemical performance and superior long-term cycle stability.Organic materials are regarded as promising anode materials for constructing SIBs with high capacity and good retention.However,utilization of organic materials is rather limited by their low energy density and poor stability at high current densities.To overcome these limitations,we utilized a novel polymeric disodium phthalocyanines(pNaPc)as SIB anodes to provide stable coordination sites for Na ions as well as to enhance the stability at high current density.By varying the linker type during a one-pot cyclization and polymerization process,two pNaPc anodes with O-(O-pNaPc)and S-linkers(S-pNaPc)were prepared,and their structural and electrochemical properties were investigated.The O-pNaPc binds Na ions with a lower binding energy compared with S-pNaPc,which leads to more facile Na-ion coordination/dissociation when engaged as SIB anode.The use of O-pNaPc significantly improves the redox kinetics and cycle stability and allows the fabrication of a full cell against Na_(3)V_(2)(PO_(4))_(2)F_(3)/C cathode,which demonstrates its practical application with high energy density(288 Wh kg^(-1))and high power density(149 W kg^(-1)).
基金supported jointly by the National Knowledge Innovation Pro-gram of the Chinese Academy of Sciences (KZCX2-YW-102)the National Natural Science Foundation of China (40525011, 40632011)
文摘Previous studies showed that water chemistry and concentrations of dissolved organic matter (DOM) could affect its molecular conformation and binding characteristics with hydrophobic organic contaminants (HOCs). However, the conformational change of DOM resultant from water chemistry and concentrations of DOM was not extensively investigated; therefore, the contradictory reports regarding the binding property with HOCs were available in literature. In this study, the effects of ionic strength, pH and DOM concentrations on the fluorescence properties of two humic acids (HA), namely Fluka HA and Amherst HA, were investigated by three-dimensional excitation-emission matrix fluorescence spectroscopy (3DEEM) and steady-state fluorescence polarization (FP) techniques. The results not only corroborated previous observations obtained by other investigators, but revealed some new information about the fluorescence properties and molecular conformation of the humic acids under different water chemistry and DOM concentration conditions, which could shed light on its binding mechanisms and binding properties with HOCs.
文摘Overall, General, Organic, and Biological Chemistry is a very useful text to support a twosemester undergraduate course series in chemistry for health sciences students. Its strengths are the use of the P.A.V.E. way to student learning applications. It is very obvious that the author has the background and the preparation of the student taking the course(s) in mind when she was writing the textbook.
文摘Different imines were prepared.The reaction was carried out using different conditions,with aromatic aldehydes,aniline and with different energy sources.Yield,purity and experimental fusion point were calculated in each case,and they were compared to the ones found in literature.The importance of structural effects of aldehyde reacting with aniline was established as well as reaction conditions.The efficacy of the reaction can not be predicted,since each aldehyde has a different structure and therefore reacts differently.The main objective of this project is academic.A methodology to carry out a structured research(it is one of the levels of problem-based learning(ABP)),was implemented.Students work in pairs using Combinatorial Chemistry,and each pair does a different exercise on the same theoretical objective.Results from every team are discussed in a seminary where conclusions regarding which was the most efficient reaction are reached.
基金supported by the NSFC/RGC Joint Research Scheme 2020/21(Project No:N_City U104/20)。
文摘Employing cathode materials with multiple redox couples and electrolytes with efficient cation transport kinetics are two effective approaches to improving the electrochemical performance of batteries.In this work,for the first time,we present a design strategy of simultaneously realizing reversible cationic and anionic redox chemistries as well as selective anion/cation transport in the viologen-based COFs(BAVCOF:X,coordinated anions of X=Cl^(-),Br^(-),I^(-),and ClO_(4)^(-))for high-performance Na-ion cathodes.Besides the cationic redox of viologen segments,the different redox activities of anions effectively tune the total capacities of the COFs.Meanwhile,electrochemical analysis and ab-initial molecular dynamics(AIMD)calculation illustrate that the anion/cation transport kinetics of electrolytes caged in the COFs'channels can be selectively tuned by the coordinated anions.As a result,combining high-potential Br-/Br_(2)redox couple,cationic redox of viologen segments,and enhanced Na+transport kinetics,the BAV-COF:Brdemonstrates stable performance with energy densities of 358.7 and 145.2 Wh kg^(-1)at power densities of 116.5 and 2124.1 W kg^(-1),respectively.This study offers new insight into the fabrication of organic cathodes with anionic redox and the advantages of COFs electrode materials in anion/cation transport selectivity for energy storage applications.
文摘To realistically simulate the impacts of marine isoprene and primary organic aerosols (POA) on atmospheric chemistry, a unified model framework with online emissions, comprehensive treatment of gas-phase chemistry, and advanced aerosol microphysics is required. In this work, the global-through-urban WRF/Chem model (GU-WRF/Chem) implemented with the online emissions of marine isoprene and size-resolved marine POA is applied to examine such impacts. The net effect of these emissions was increased surface concentrations of isoprene and organic aerosols and decreased surfaced concentrations of hydroxyl radical and ozone over most marine regions. With the inclusion of these emissions, GU-WRF/Chem better predicted the surface concentrations of isoprene and organic aerosols and the aerosol number size distribution when compared to measurements in clean marine conditions.
基金Supported by 2011 Shaanxi Higher Education Teaching Reform Program(11BY12)
文摘From the perspective of students,the effectiveness of task-based approach in In-organic and Analytical Chemistry course were summarized.The strength and weak points of TBA were analyzed,and the specific suggestions for obtaining better effect were put forward.The result showed a satisfactory achievement and unexpected result in showing the effectiveness of this teaching model.Not only could this TBA enhance student's overall knowledge of discipline but also cultivate students' multi-dimensional competence:competence in searching literatures, communication and management,autonomous,co-operative and reflective learning,and competence in analyzing and problem-solving,as well as improving their language expression ability,and skills in using multi-media and internet technology into their academic course learning and research.The implication of this research on the classroom teaching practice will shed light on the future teaching reform of other courses in China.
文摘After a disciplinary upsurge, organic chemistry is about to embark on an epoch-making transition at the turn of the century. At present when the discipline is once again making its way into life sciences, this article gives a running commmentary on its current state and some developmental trends making a debut in this new research orientation. Finally, several ideas are aired to the community of Chinese chemists, advising them on how to welcome the historic transition.
基金supported by the National Natural Science Foundation of China(22071004,21933001 and 22150013)
文摘Organic chemistry is undergoing a major paradigm shift,moving from a labor-intensive approach to a new era dominated by automation and artificial intelligence(AI).This transformative shift is being driven by technological advances,the ever-increasing demand for greater research efficiency and accuracy,and the burgeoning growth of interdisciplinary research.AI models,supported by computational power and algorithms,are drastically reshaping synthetic planning and introducing groundbreaking ways to tackle complex molecular synthesis.In addition,autonomous robotic systems are rapidly accelerating the pace of discovery by performing tedious tasks with unprecedented speed and precision.This article examines the multiple opportunities and challenges presented by this paradigm shift and explores its far-reaching implications.It provides valuable insights into the future trajectory of organic chemistry research,which is increasingly defined by the synergistic interaction of automation and AI.
基金Supported by the National Natural Science Foundation of China(Nos.20737002,41073087)
文摘The binding constant(KDOM) of pyrene onto different molecular weight(Mw) fractions of a dissolved organic matter(DOM) extract from an estuarine sediment was measured via a fluorescence quenching method,and the possible binding mechanisms were discussed.The influence of water chemical parameters on pyrene binding was studied to elucidate the effects of DOM steric conformation.DOM fraction with larger M w(14000) showed a greater KDOM(2.02×10 5) than that with smaller Mw did,and the KDOMs were 1.16×105 and 1.13×105 for the fractions with M w of 1000―14000 and 1000,respectively.The K DOM s of different M w DOM fractions were correlated positively with the atomic ratio of C/H and absorbance at 280 nm;while a negative correlation existed between K DOM and(O+C)/N(atomic ratio),and K DOM and O-containing groups.These correlations indicate the positive influence of aromatic structure and the negative effect of polarity on DOM binding capacity.Infrared spectroscopy revealed that specific interactions existed between pyrene and the DOM fraction with larger M W besides hydrophobic partition,i.e.,NH-π interaction in DOM moiety(1000―14000) and π-π electron donor acceptor(EDA) forces in DOM moiety(14000).KDOM varied in a complex pattern with increasing cation concentration and pH,which could be explained by the change in DOM steric conformation.Formed aggregates favored the lipophilic partition of pyrene.However,the accessibility to some interior binding sites became low when the aggregate was too large,leading to a reduced KDOM.
文摘OMGKRP is one of various Karuho poison mysteriously used by unscrupulous individuals to kill people during conflict and animals in Goma City, in DRC. The symptoms and signs of most cases are usually confused with many chronic diseases like tuberculosis and HIV/AIDS;with renal, hepatic and cardiac manifestations as well as blood chemistry changes. The study investigated the toxic effect of OMGKRP poison on blood chemistry, serum enzymes and organ toxicity including the kidney, lung, liver and heart of Wistar albino rats. A laboratory-based experimental study was conducted. Fifty animals in 5 groups each with 10 animals were dosed daily for 28 days with 1.0 mg, 5.0 mg, 20.0 mg and 5000.0 mg/Kg body weight of OMGKRP and normal saline as control group. International standard guidelines, OECD 407 and NIH 2011 were followed during the study period. The blood chemistry analysis, relative organ weight and histopathological changes in the kidney, lung, liver and heart were performed. The findings showed that OMGKRP was associated with increased blood chemistry parameters including total proteins, creatinine, urea, K+?levels, direct albumin levels, a decrease in Cl−?levels and albumin levels. Histopathological findings showed an increased relative weight and tissue damages of the lung, kidney, liver and heart. Therefore, OMGKRP Karuho poison caused toxicity on blood chemistry, serum enzymes as well as histopathological changes in the lung, renal, hepatic and cardiac tissue damages in Wistar albino rats.