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Evaluation of Pesticide Toxicity and Chemical Compounds Revealed in Soils of Sikasso and Segou (Mali)
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作者 Vital Traoré Abdrahaman Sidibé +5 位作者 Ahoua Sika Edmond Alou Coulibaly Kalifa Keïta Drissa Samake Daniel Traoré Sergey Kotelevtsev 《Journal of Agricultural Chemistry and Environment》 2016年第1期35-44,共10页
The contaminants of the ground are potentially harmful agents and when they are released in this medium, their persistence becomes an important concern. Because of the expressed interest, a certain number of pesticide... The contaminants of the ground are potentially harmful agents and when they are released in this medium, their persistence becomes an important concern. Because of the expressed interest, a certain number of pesticides and important chemicals and their toxicity are described in this article. The studies went on the determination of the concentration, the lethal amount of the organochlorinated compounds, chemical organophosphates, carbamates and compounds. One summer recorded 3 pesticides in 5 samples of the grounds of Sikasso and Segou (Mali). Their concentration varies from 20 (atrazine) with 45 g/kg of ground. The lethal amounts of the revealed poisons variable from 338 for phtalates to 28.710 mg/kg for hexane (alkane) thus evaluate their impact on the food chain. Organophosphates and the carbamates (insecticidal) involve a reduction of 34.2% of the number of Cyprinus carpio of fresh water. The atrazine contaminates drinking water, but the diuron modifies the behavior and the reproduction of fish by deteriorating their system of olfactive perception of natural substances. Important mortalities of birds are noted around the corn fields of Bougouni treated by the carbofuran. The pesticides involve at the man a reduction in fruitfulness, an increase in the risk of miscarriage of premature birth, congenital malformations and cancers. 展开更多
关键词 EVALUATION TOXICITY PESTICIDES chemical compounds Soils of Sikasso and Segou
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Changes in Chemical Composition of Soluble Organic Chemical Compounds during Litters Decomposition into Tropical Forest of Milletia laurentii De Wild
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作者 Gouolaly Tsiba Mavoungou Naiving Flovique Rosère +5 位作者 Edzonga Josianne Milandou Matoko Jodhry Préféré Malonga Urielle Marini Madingou Parfait Noé Binsangou Stoffenne Ifo Suspense Averti 《Open Journal of Forestry》 2019年第1期70-87,共18页
Recent publication attested that in the urban forest of Brazzaville, litter decomposition is faster with almost 45% of initial weight loss than in the dry season, where an average loss of 26% in initial litter weight ... Recent publication attested that in the urban forest of Brazzaville, litter decomposition is faster with almost 45% of initial weight loss than in the dry season, where an average loss of 26% in initial litter weight is noted (Ifo et al., 2018). This study was carried out in the urban forest of Brazzaville to follow the decomposition of some organic compounds/secondary metabolites (reducing Sugars, total Flavonoid and Polyphenols) of the leaves litters of two tropical species Antiaris toxicaria Lesch and Millettia laurentii De Wild. Thin-layer chromatography and spectrophotometric assay of these metabolites were used on the samples of litters collected in the field on various dates of follow-up of the decomposition (0 d, 14 d, 28 d, 42 d, 56 d, 72 d and 84 d). The chromatographic profile of initial litters shows a series of spots on yellow florescence materializing presence of flavonoids, green fluorescence revealing the presence of the acids phenols derived from the cinnamic acid. But the chromatographic profile of the two litters in decomposition after two weeks remains without structural information, being able to characterize the decomposition of the chemical families highlighted in the initial litters. Also, the analysis of quantitative total reducing sugar in the initial litters, gives average concentrations of 64.4, 58.6, 57.5 g EG/kg Ms respectively for the litters of Millettia laurentii De Wild, Antiaris toxicaria Lesch and the mixed litters (Millettia laurentii and Antiaris toxicaria). Comparatively with the other types of litters, the initial average concentrations in phenolic compounds (polyphenols and flavonoids totals) were the highest for the litters of Antiaris toxicaria Lesch (27.3 g EAG/kg Ms and 13.07 g EC/kg Ms) (P = 0.001). The losses of organic chemical compounds are more significant during the first two weeks of experiment than after this period. Antiaris toxicaria Lesch loses on average 43.8 g EG/kg Ms of reducing Sugars, 12.21 g EC/kg Ms of totals flavonoids and 26.4 g EAG/kg Ms of total polyphenols, equivalent to 30% of loss of the initial weight. Average losses of 45.7 g EG/kg Ms were obtained for reducing sugars, 1.5 g EC/kg Ms for totals flavonoids and 8.72 g EAG/kg Ms for totally phenols in for the litters of Millettia laurentii, comparable to 24% in initial weight loss. This study showed on the one hand, the direct link between rainfall and litters decomposition and the losses in weight of the litters resulted in dissolution in the water of the studied compounds. 展开更多
关键词 Tropical Urban Forest Litter Decomposition Organic chemical compounds
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Cocktail of chemical compounds robustly promoting cell reprogramming protects liver against acute injury 被引量:1
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作者 Yuewen Tang Lin Cheng 《Protein & Cell》 SCIE CAS CSCD 2017年第4期273-283,共11页
Tissue damage induces cells into reprogramming-like cellular state, which contributes to tissue regeneration. However, whether factors promoting the cell repro- gramming favor tissue regeneration remains elusive. Here... Tissue damage induces cells into reprogramming-like cellular state, which contributes to tissue regeneration. However, whether factors promoting the cell repro- gramming favor tissue regeneration remains elusive. Here we identified combination of small chemical com- pounds including drug cocktails robustly promoting in vitro cell reprogramming. We then administrated the drug cocktails to mice with acute liver injuries induced by partial hepatectomy or toxic treatment. Our results demonstrated that the drug cocktails which promoted cell reprogramming in vitro improved liver regeneration and hepatic function in vivo after acute injuries. The underlying mechanism could be that expression of pluripotent genes activated after injury is further upregulated by drug cocktails. Thus our study offers proof-of-concept evidence that cocktail of clinical com- pounds improving cell reprogramming favors tissue recovery after acute damages, which is an attractive strategy for regenerative purpose. 展开更多
关键词 cell reprogramming chemical compounds liver regeneration
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Technology Development and Production of Certain Chemical Platinum Metals Compounds at JSC "Krastsvetmet"
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作者 ILYASHEVICH V. D. PAVLOVA E. I. KORITSKAYA N. G. MAMONOV S. N. SHULGIN D. R. MALTSEV E. V. 《贵金属》 CAS CSCD 北大核心 2012年第A01期85-87,共3页
In recent years JSC "Krastsvetmet" has successfully developed the production of chemically pure compounds of precious metals.Currently methods have been developed and facilities have been provided for indust... In recent years JSC "Krastsvetmet" has successfully developed the production of chemically pure compounds of precious metals.Currently methods have been developed and facilities have been provided for industrial production of the following platinum metals compounds:Rhodium(Ⅲ) chloride hydrate,rhodium(Ⅲ) chloride solution,rhodium(Ⅲ) nitrate solution,rhodium(Ⅲ) iodide,rhodium(Ⅲ) sulfate,hydrated rhodium(Ⅲ) oxide,ammonium hexachlororodiate,rhodium(Ⅲ) phosphate solution,rhodium electrolytes;Iridium(Ⅳ) chloride hydrate,iridium(Ⅲ) chloride hydrate,ammonium hexachloroiridate(Ⅳ),hexa chloriridium acid solution,hexachloriridium crystalline acid;Ruthenium(Ⅲ) chloride hydrate,ruthenium(Ⅳ) hydroxide chloride,ruthenium(Ⅳ) hydroxide chloride solution,ammonium hexachlororuthenate,ruthenium(Ⅲ) chloride solution,potassium,diaquaoctachloronitrido diruthenate.The quality of the production meets the requirements of Russian and foreign consumers. 展开更多
关键词 refined metal feeding materials recovery process solutions crystal hydrates precious metals chemical compounds
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PARTIAL RECONSTITUTION OF BOTANICAL EXTRACT PG102 BY COMBINING CHEMICAL COMPOUNDS KNOWN TO BE PRESENT IN ACTINIDIA ARGUTA: IMPLICATIONS FOR QC OF PHYTOMEDICINES
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作者 Doo Suk Lee Sunyoung Kim 《World Journal of Traditional Chinese Medicine》 2015年第4期91-91,共1页
One of the most important factors limiting the success of plant-derived therapeutics is that these products are generally a mixture containing many different molecules.The compounds responsible for bioactivities and/o... One of the most important factors limiting the success of plant-derived therapeutics is that these products are generally a mixture containing many different molecules.The compounds responsible for bioactivities and/or clinical effects are also not yet identified.To overcome this hurdle,we investigated whether we can reconstitute bioactivities 展开更多
关键词 PG IMPLICATIONS FOR QC OF PHYTOMEDICINES PARTIAL RECONSTITUTION OF BOTANICAL EXTRACT PG102 BY COMBINING chemical compoundS KNOWN TO BE PRESENT IN ACTINIDIA ARGUTA
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The study on the chemical valence and compound form of Arsenic in water in Hetao area of the Inner Mongolia
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《Global Geology》 1998年第1期39-39,共1页
关键词 area The study on the chemical valence and compound form of Arsenic in water in Hetao area of the Inner Mongolia
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Antibacterial enhancement of antibiotic activity by Enterolobium contortisiliquum(Vell.)Morong
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作者 Zildene de Sousa Silveira Nair Silva Macêdo +8 位作者 Thiago Sampaio de Freitas Ana Raquel Pereira da Silva Joycy Francely Sampaio dos Santos Maria Flaviana Bezerra Morais-Braga José Galberto Martins da Costa Raimundo Nonato Pereira Teixeira Jean Paul Kamdem Henrique Douglas Melo Coutinho Francisco Assis Bezerra da Cunha 《Asian Pacific Journal of Tropical Biomedicine》 CAS 2017年第10期945-949,共5页
Objective: To identify the main chemical classes of compounds from aqueous extract of Enterolobium contortisiliquum(E. contortisiliquum) seed bark and to evaluate its antibacterial activity, as well as its potential t... Objective: To identify the main chemical classes of compounds from aqueous extract of Enterolobium contortisiliquum(E. contortisiliquum) seed bark and to evaluate its antibacterial activity, as well as its potential to increase the activity of antibiotics against strains of Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli.Methods: Different classes of compounds in the aqueous extract of E. contortisiliquum were evaluated based on the visual changes in the coloration and the formation of precipitate after the addition of specific reagents. The antibacterial activity of the extract and its potential to increase of antibiotic activity of antibiotics drugs, gentamicin and norfloxacin was determined by using the microdilution method.Results: Our results demonstrated that the following secondary metabolites were presented in E. contortisiliquum seed bark: flavones, flavonols, xanthones, flavononols,chalcones, aurones, flavones and catechins. The extract itself had very low antibacterial activity against all bacterial strains tested(MIC ≥ 1024 μg/m L), but there was an increase in the antibiotic activity of gentamicin and norfloxacin when combined in the subinhibitory concentration(i.e., MIC/8).Conclusions: Our data suggests that E. contortisiliquum seed bark may be an alternative source for new drugs with the potential to increase antibiotic activity against different strains of bacteria. 展开更多
关键词 Antibiotic activity ENHANCEMENT Synergism chemical compounds Bioactivity
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Polynomials of Degree-Based Indices for Three-Dimensional Mesh Network
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作者 Ali N.A.Koam Ali Ahmad 《Computers, Materials & Continua》 SCIE EI 2020年第11期1271-1282,共12页
In order to study the behavior and interconnection of network devices,graphs structures are used to formulate the properties in terms of mathematical models.Mesh network(meshnet)is a LAN topology in which devices are ... In order to study the behavior and interconnection of network devices,graphs structures are used to formulate the properties in terms of mathematical models.Mesh network(meshnet)is a LAN topology in which devices are connected either directly or through some intermediate devices.These terminating and intermediate devices are considered as vertices of graph whereas wired or wireless connections among these devices are shown as edges of graph.Topological indices are used to reflect structural property of graphs in form of one real number.This structural invariant has revolutionized the field of chemistry to identify molecular descriptors of chemical compounds.These indices are extensively used for establishing relationships between the structure of nanotubes and their physico-chemical properties.In this paper a representation of sodium chloride(NaCl)is studied,because structure of NaCl is same as the Cartesian product of three paths of length exactly like a mesh network.In this way the general formula obtained in this paper can be used in chemistry as well as for any degree-based topological polynomials of three-dimensional mesh networks. 展开更多
关键词 Topological polynomials degree-based index three-dimensional mesh network chemical compounds
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Chemical transdifferentiation: closer to regenerative medicine 被引量:1
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作者 Aining Xu Lin Cheng 《Frontiers of Medicine》 SCIE CAS CSCD 2016年第2期152-165,共14页
Cell transdifferentiation, which directly switches one type of differentiated cells into another cell type, is more advantageous than cell reprogramming to generate pluripotent cells and differentiate them into functi... Cell transdifferentiation, which directly switches one type of differentiated cells into another cell type, is more advantageous than cell reprogramming to generate pluripotent cells and differentiate them into functional cells. This process is crucial in regenerative medicine. However, the cell-converting strategies, which mainly depend on the virus-mediated expression of exogenous genes, have clinical safety concerns. Small molecules with compelling advantages are a potential alternative in manipulating cell fate conversion. In this review, we briefly retrospect the nature of cell transdifferentiation and summarize the current developments in the research of small molecules in promoting cell conversion. Particularly, we focus on the complete chemical compound-induced cell transdifferentiation, which is closer to the clinical translation in cell therapy. Despite these achievements, the mechanisms underpinning chemical transdifferentiation remain largely unknown. More importantly, identifying drugs that induce resident cell conversion in vivo to repair damaged tissue remains to be the end-goal in current regenerative medicine. 展开更多
关键词 cell therapy cell transdifferentiation chemical compounds small molecules tissue regeneration
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Pharmacological potentials of phenolic compounds from Prosopis spp.-a review
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作者 Dhananjaya Seturaman Prabha Hans-Uwe Dahms Prabha Malliga 《Journal of Coastal Life Medicine》 2014年第11期918-924,共7页
The shrub Prosopsis juliflora(Sw.)DC.revealed several medicinal properties due to its different chemical compounds such as alkaloids,flavonoids,terpenoids,saponins and phenolic compounds distributed in different parts... The shrub Prosopsis juliflora(Sw.)DC.revealed several medicinal properties due to its different chemical compounds such as alkaloids,flavonoids,terpenoids,saponins and phenolic compounds distributed in different parts of the plant body,such as woody parts(roots,stem,branches and bark)as well as leaves and pollen have been used for the extraction of medically active substances.Prosopsis juliflora containing a diverse group of secondary metabolites has unique and multifactorial medicinal properties.The utilization of this abundant resource provides a viable option for producing bioactive natural products that may serve as lead substances for the chemical and pharmaceutical industries.This review highlights accessible bioactive sources from this plant that are of potential interest for industrial applications. 展开更多
关键词 industrial applications secondary metabolites phenolic compounds chemical compounds active substances natural products
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Comparative analysis of four active compounds of Baikal skullcap and its classical TCM prescriptions according to different clinical curative effects
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作者 Guang-Wei Zhu Sheng-Jun Ma Ao-Xue Liu 《World Journal of Traditional Chinese Medicine》 2017年第1期22-30,共9页
Objective: A sensitive HPLC-DAD detection method was established for the comparative analysis of the four active compounds(including baicalin, baicalein, wogonoside and wogonin) of Baikal Skullcap and its classical TC... Objective: A sensitive HPLC-DAD detection method was established for the comparative analysis of the four active compounds(including baicalin, baicalein, wogonoside and wogonin) of Baikal Skullcap and its classical TCM prescriptions according to different clinical curative effects. And analyze the relationship between compatibility of medicines, content and clinical curative effect.Methods: Water extracts were analyzed by high-performance liquid chromatography-diode array detection(HPLC-DAD), using an Agilent extend-C_(18)(4.6 mm×250 mm,5μm) column by using solvent A(0.2% phosphoric acid water) and solvent B(methanol) in the ratio of 52:48(v/v) at a flow rate of 1 ml/min. The column temperature was maintained at 25°C and the detection wavelength was set at 280 nm.Results: In quantitative analysis, the four selected markers showed good regression(R^2>0.999) within test ranges. The average recoveries were between 99.75~100.60% and their RSD values were between 0.97%~1.71%. The proportions of the four chemical compounds for different efficacy were 33.51~35.76: 6.78~6.87: 3.45~3.64: 1; 18.6~23.64: 3.63~4.27: 1.36~1.53: 1; 29.94~31.78: 5.14~5.23: 3.28~3.56: 1; 33.99~41.91:5.83~7.42: 2.83~3.39: 1.Conclusion: Clinical practice of thousands of years have proved that the curative effect of Traditional Chinese Medicine depends on the compatibility of different kinds of medicine material crude slices. According to this study we found that different compatibility of medicines leads to different proportions of the chemical compounds. We assume that there is a certain correlation between therapeutical effect of TCM and compatibility of medicines. 展开更多
关键词 Baikal skullcap Couplet medicine Clinical curative effect Compatibility of medicines Proportions of the chemical compounds
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Controlled preparation and self-assembly of NdVO_4 nanocrystals 被引量:1
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作者 Li Tian Yan Li +7 位作者 Huifeng Wang Shanmin Chen Jinjing Wang Zhen Guo Qiang Liu Qi Luo Yingjie Li Fafa Wu 《Journal of Rare Earths》 SCIE EI CAS CSCD 2018年第2期179-183,共5页
Phase-pure t-NdVO_4 nanocrystals with different shapes have been synthesized by facile and repeatable hydrothermal methods. The as-synthesized t-NdVO_4 nanoparticles were characterized by various techniques of X-ray d... Phase-pure t-NdVO_4 nanocrystals with different shapes have been synthesized by facile and repeatable hydrothermal methods. The as-synthesized t-NdVO_4 nanoparticles were characterized by various techniques of X-ray diffraction(XRD). scanning electron microscope(SEM) and transmission electron microscope(TEM). The growth process and assembly behavior of t-NdVO_4 nanorod arrays were investigated. The results show that the morphology of t-NdV04 nanocrystals is greatly related to the pH value of precursor solution and that strong basic solution is not in favor of the formation of t-NdVO_4 nanoparticles. Due to the strong adhesive action and stabilization of OH^-ions to some crystal faces of NdVO_4, neodymium vanadate crystallite grows into oriented short nanorods and then into nanorod arrays. The shape, crystalline and dimension of NdVO_4 nanocrystals can be effectively governed in our work. 展开更多
关键词 Inorganic compounds Nanostructures chemical synthesis X-ray diffraction Rare earths
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Hydrothermal synthesis and optical properties of Zn_(1-x)Mn_xS nanorods
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作者 Yangfeng Huang Yebin Cai Hao Liu 《Particuology》 SCIE EI CAS CSCD 2011年第5期533-536,共4页
Zn1-xMnxS (x = 0-0.05) nanorods were successfully synthesized through a hydrothermal route. The morphology, composition and microstructure of Zn1-xMnxS nanorods were characterized respectively by X-ray diffraction ... Zn1-xMnxS (x = 0-0.05) nanorods were successfully synthesized through a hydrothermal route. The morphology, composition and microstructure of Zn1-xMnxS nanorods were characterized respectively by X-ray diffraction (XRD), scanning electron microscopy (SEM) and Raman spectrometer. The optical properties of Zn1-xMnxS nanorods were determineded by UV-Vis absorption spectroscopy and photo- luminescence (PL) emission spectroscopy. The results show that the introduction of Mn^2+ on interstitial sites in ZnS lattice has significant influence on the Raman spectra, UV-Vis absorption spectra and PL emis- sion spectra. With the increase of Mn^2+, the lengths of the sampled nanorods become shorter and the morphologies of the products show disorder accompanied by some nanoparticles. The absorption band edge shifts to longer wavelength. The intensity of the ZnS-related emission gradually becomes weaker, whereas, the Mn^2+-related broad emission spectra located at 580 nm gradually red-shifts and increases. Occupation of Zn^2+ sites in the lattice by Mn^2+ ions results in lattice distortion and influences the energy level structure of ZnS. The Mn doping is found responsible for the changes in the defect-related emission of the ZnS nanorods. 展开更多
关键词 Inorganic compound chemical synthesis Nanostructures Optical properties
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