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Quantitative Extraction of p-Coumaric Acid and Ferulic Acid in Different Gramineous Materials and Structural Changes of Residual Alkali Lignin
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作者 Tanhao Zhang Shuo Zhang +1 位作者 Wu Lan Fengxia Yue 《Journal of Renewable Materials》 SCIE EI 2023年第2期555-566,共12页
Ferulic acid(FA)and p-coumaric acid(pCA)in bagasse,wheat straw,corn straw,and corncob were extracted by alkaline hydrolysis and characterized by gas chromatography(GC)and gas chromatography-mass spectrometry(GC-MS).It... Ferulic acid(FA)and p-coumaric acid(pCA)in bagasse,wheat straw,corn straw,and corncob were extracted by alkaline hydrolysis and characterized by gas chromatography(GC)and gas chromatography-mass spectrometry(GC-MS).It was found that the FA and most of the pCA in gramineous biomass could be dissociated and released after being treated with 1 M NaOH at 100℃for 4 h.The yields of pCA/FA in bagasse,wheat straw,corn straw,and corncob determined by GC-FID are 39.8/11.5,13.7/11.0,28.0/11.0,and 35.1/14.5 mg/g,respectively.The raw materials and the treated solid residues were characterized by gel-state 2D Heteronuclear Single Quantum Coherence Nuclear Magnetic Resonance(2D HSQC NMR).It was found that only a small amount of lignin was detected in the residue after alkali treatment,indicating that the alkali treatment conditions can effectively cleave the FA and pCA.Additionally,the lignin in the alkali solution was recovered and characterized by 2D HSQC NMR.The FA was not able to be detected by NMR,whereas a small amount of pCA remained in the alkali lignin.This study reveals the structural change of residual lignins during the quantitative isolation of FA and pCA,which is essential for the selective isolation of pCA/FA and valorization of residual alkali lignin. 展开更多
关键词 GRAMINEAE ferulic acid p-coumaric acid alkali lignin alkaline pretreatment
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Analysis of Organic Acids Accumulated in Kochia Scoparia Shoots and Roots by Reverse-phase High Performance Liquid Chromatography Under Salt and Alkali Stress 被引量:7
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作者 YAN Hong ZHAO Wei +2 位作者 JIAO Xin-qian YAN Bing-jun ZHOU Dao-wei 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2006年第3期315-318,共4页
Several organic acids accumulated in Kochia Scoparia shoots and roots were studied by means of reverse-phase high performance liquid chromatography with a C18 column. Five types of binary organic acids were separated.... Several organic acids accumulated in Kochia Scoparia shoots and roots were studied by means of reverse-phase high performance liquid chromatography with a C18 column. Five types of binary organic acids were separated. The organic acid concentrations were determined in K. Scoparia seedlings stressed by saline (NaCI) and alkaline (NaHCO3) at the same Na^+ concentration. Concentrations of organic acids are stimulated by alkaline because the cells will adjust their pH values through the accumulation of organic acids, when the environment is basic. The concentrations of oxalic acid and succinic acid are higher than those of other organic acids, including tartaric acid and malic acid, and the concentration of citric acid is the lowest. The concentrations of the organic acids in the roots are higher than those in the shoots under salt(NaCI) stress, but the results are opposite while the roots are under alkali ( NaHCO3 ) stress. This indicates that there are different adaptive strategies for K. Scopar/a seedlings in organic acid metabolism under salt and alkali stress. 展开更多
关键词 Kochia Scoparia(L. Sehrad salt stress alkaline stress Organic acid HPLC
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Effect of Ascorbic Acid and Silicium on Photosynthesis, Antioxidant Enzyme Activity, and Fatty Acid Contents in Canola Exposure to Salt Stress 被引量:9
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作者 Ahmad Bybordi 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2012年第10期1610-1620,共11页
The effects of exogenous ascorbic acid and silicium on leaf fresh weigh, seed yield, photosynthesis, changes of the activities of major antioxidant enzymes, nitrate reductase activity, proline accumulation, chlorophyl... The effects of exogenous ascorbic acid and silicium on leaf fresh weigh, seed yield, photosynthesis, changes of the activities of major antioxidant enzymes, nitrate reductase activity, proline accumulation, chlorophyll content, and fatty acid composition were investigated in salt-stressed canola. A hydroponic pot experiment was conducted based on randomized complete block design, factorial arrangement was used with 16 combinations of salinity stress (0, 100, 200, and 300 mmol L-1 NaC1), ascorbic acid (0 and 30 mmol L-1), and silicium (2 and 4 mmol L-1 from potassium silicate) with three replicates. The results showed that salinity significantly decreased leaf area and leaf fresh weight, seed yield, photosynthesis, nitrate reductase activity, chlorophyll content, and seed protein percentage. Conversely, respiration, antioxidant enzymes activity, proline accumulation, and linolenic acid percentage increased due to salt stress. Ascorbic acid application improved photosynthesis and seed yield and mitigated antioxidant enzyme activity. In addition, nitrate reductase activity and chlorophyll a and b were positively affected by ascorbic acid. Regarding silicium application, that was found that leaf area, leaf fresh weight, seed yield and photosynthesis, ascorbate peroxidase activity, nitrate reductase activity, and chlorophyll content increased, while respiration decreased. Furthermore, silicium had not significant effect on antioxidant enzyme activity. In general, ascorbic acid and silicium were involved in the defensive mechanisms against salinity stress and it can be suggested that, ascorbic acid and silicium application had positive effect on canola growth under conditions of salt stress. 展开更多
关键词 ascorbic acid salt stress CANOLA SILICIUM
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Effects of Exogenous Trehalose on the Metabolism of Sugar and Abscisic Acid in Tomato Seedlings Under Salt Stress 被引量:4
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作者 Yanchun Feng Xiuyu Chen +2 位作者 Yulong He Xiaohong Kou Zhaohui Xue 《Transactions of Tianjin University》 EI CAS 2019年第5期451-471,共21页
Salt stress a ects the growth and development of plants, which results in a decrease in crop quality and yield. In this study, we used tomato seedlings treated with salt and trehalose as experimental materials and ana... Salt stress a ects the growth and development of plants, which results in a decrease in crop quality and yield. In this study, we used tomato seedlings treated with salt and trehalose as experimental materials and analyzed them using the technique for order preference by similarity to ideal solution analysis to select the optimal trehalose concentration for treatment. We also determined the contents of sugar and abscisic acid (ABA) and detected the expression of genes involved in the metabolism of sugar and ABA by quantitative real-time PCR. Results showed that the optimal trehalose concentration was 2 mmol/L for tomato seedlings under salt stress. Exogenous trehalose decreased the starch content and increased the soluble sugar con- tent by a ecting the expression of genes related to the metabolism of starch and soluble sugar. Exogenous trehalose altered the accumulation and distribution of sugar by inducing the upregulation of sugar transporter genes. Furthermore, trehalose increased the ABA content to induce salt stress response by regulating the expression of genes related to the synthesis and metabolism of ABA. In conclusion, trehalose can e ectively alleviate salt stress and enhance salt tolerance of tomato. These ndings provide a novel perspective and a better resource to investigate the salt tolerance mechanism and a new method for alleviating salt stress in tomato. 展开更多
关键词 Tomato TREHALOSE salt stress SUGAR METABOLISM SUGAR TRANSPORTER Abscisic acid
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Cloning of Bile Salt Hydrolase Gene and Its Expression in Lactic Acid Bacteria 被引量:3
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作者 LI Bin JIANG Yujun 《Journal of Northeast Agricultural University(English Edition)》 CAS 2011年第2期48-53,共6页
According to the sequence of the bile salt hydrolase (BSH) gene of Bifidobacterium and the restriction enzyme cutting sites of expression vector pNZ8148, primers were designed and the bile salt hydrolase (BSH) gen... According to the sequence of the bile salt hydrolase (BSH) gene of Bifidobacterium and the restriction enzyme cutting sites of expression vector pNZ8148, primers were designed and the bile salt hydrolase (BSH) gene was gotten from Bacillus bifidus ATCC 29521 by PCR. BSH gene was inserted into lactic acid bacteria expression vector pNZ8148 to construct the recombinant pNZ8148-BSH. The recombinant pNZ8148-BSH was transferred into lactic acid bacteria NZ9000 with electrotransformation method. And the recombinant which could express BSH protein was obtained. It was identified by SDS-PAGE electrophoresis and activity verification. The result could provide a rationale reference for expressing BSH in lactic acid bacteria. 展开更多
关键词 bile salt hydrolase lactic acid bacteria gene cloning IDENTIFICATION recombinant expression
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Effect of bile salts and bile acids on human gastric mucosal epithelial cells 被引量:2
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作者 Yinxue Song Jun Gong 《Journal of Nanjing Medical University》 2008年第4期217-223,共7页
Objective:To explore the effect of bile salt and bile acid on cultured eternalized human gastric mucosa epithelium GES-1 cells. Methods:Cultured eternalized human gastric mucosa epithelium GES-1 cells were treated w... Objective:To explore the effect of bile salt and bile acid on cultured eternalized human gastric mucosa epithelium GES-1 cells. Methods:Cultured eternalized human gastric mucosa epithelium GES-1 cells were treated with media containing 6 different kinds of bile salts and 3 different kinds of bile acids and their mixture with different concentrations: GCDC(glycochenodeoxychoμte), GDC (glycodeoxychoμte), GC(glycochoμte), TCDC(taurochenodeoxychoμte), TDC(taurodeoxychoμte), TC (taurochoμte), LCA (lithocholicacid), CA(cholic acid), DCA(deoxycholic acid)(50 μ mol/L,250 μ mol/L,500 μ mol/L,1000 μ mol/L), DY(mixture of bile salts) and DS(mixture of bile acids)(250 μ mol/L,500 μ mol/L,1000 μ mol/L,1500 μ mol/L, 2000 μ mol/L), in comparison with the control group(in normal media without bile salts and bile acids). Cell proliferation was assessed by MTT(3-[4,5-Dimethylthiaolyl]-2,5- diphenyl-tetrazolium bromide) assay for 72 hours with different concentrations and the apoptotic cells were assayed by flow cytometry (FCM) with Annex V-FITC conjugated with propidium iodide(PI) staining for 24 hours with different concentrations(1500,2000 μt mol/L). Results:There was no significant difference in morphology and cell proliferation in GC group after 24-72 h. Low concentration(50 μ mol/L) of GCDC, GDC, TCDC, TDC and TC accelerated gastric epithelial cell growth in a dosage-time dependent manner. At middle concentration (250-500 μ mol/L), it showed positive effect after 24-48 h, while negative effect after 72 h. At high concentration(1000 μ mol/L), it accelerated gastric epithelial cell growth after 24h and show consistent inhibition even leading to necrosis after 48-72 h. LCA and CA showed a positive effect on the concentration of 50 μ mol/L after 24-72 h, while 250-1000 μ mol/L showed a trend towards apoptosis after 24-72 h. At 50-500 μmol/L, DCA showed proliferation after 24 h and apoptosis after 48-72 h, but showed necrosis after 24-72 h at 1000 μmol/L. DY and DS could facilitate normal gastric mucosa epithelial cell growth at low concentration (250-500 μ mol/L), however at 1000-2000 μ mol/L the trend shifted from apoptosis to necrosis. FCM with Annexin-V conjugated with PI staining revealed that GCDC, GDC, GC, TCDC, TDC, TC, LCA, CA, DCA, DY and DS induced apoptosis of human gastric mucosal epithelial cells. They were all significantly higher than that of the control(P 〈 0.05), but there was no significant difference in GC group (P 〉 0.05). The bile salts induced apoptosis in a time-dose-dependent manner. Conclusion:Our results suggested that bile acid and bile salt is the trigger of injury in human gastric mucosal epithelial cells. 展开更多
关键词 bile salts bile acid duodenogastric reflux gastric mucosal epithelial cells APOPTOSIS
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A Bifunctional Brønsted Acidic Deep Eutectic Solvent to Dissolve and Catalyze the Depolymerization of Alkali Lignin 被引量:2
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作者 Lifen Li Zhigang Wu +4 位作者 Xuedong Xi Baoyu Liu Yan Cao Hailong Xu Yingcheng Hu 《Journal of Renewable Materials》 SCIE EI 2021年第2期219-235,共17页
Lignin is an abundant renewable macromolecular material in nature,and degradation of lignin to improve its hydroxyl content is the key to its efficient use.Alkali lignin(AL)was treated with Brønsted acidic deep e... Lignin is an abundant renewable macromolecular material in nature,and degradation of lignin to improve its hydroxyl content is the key to its efficient use.Alkali lignin(AL)was treated with Brønsted acidic deep eutectic solvent(DES)based on choline chloride and p-toluenesulfonic acid at mild reaction temperature,the structure of the lignin before and after degradation,as well as the composition of small molecules of lignin were analyzed in order to investigate the chemical structure changes of lignin with DES treatment,and the degradation mechanism of lignin in this acidic DES was elucidated in this work.FTIR and NMR analyses demonstrated the selective cleavage of the lignin ether linkages in the degradation process,which was in line with the increased content of phenolic hydroxyl species.XPS revealed that the O/C atomic ratio of the regenerated lignin was lower than that of the AL sample,revealing that the lignin underwent decarbonylation during the DES treatment.Regenerated lignin with low molecular weight and narrow polydispersity index was obtained,and the average molecular weight(Mw)decreased from 17680 g/mol to 2792 g/mol(130°C,3 h)according to GPC analysis.The lignin-degraded products were mainly G-type phenolics and ketones,and small number of aldehydes were also generated,the possible degradation pathway of lignin in this acidic DES was proposed. 展开更多
关键词 alkali lignin DEPOLYMERIZATION Brønsted acidic deep eutectic solvent structural analysis
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Crystal Structure,Stability and Dissolution of a Drug-drug Molecular Salt Hydrate of Berberine with Protocatechuic Acid 被引量:2
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作者 张燕杰 娄本勇 +2 位作者 黄雅丽 张梅 林棋 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2018年第3期400-406,共7页
A drug-drug molecular salt hydrate of berberine and protocatechuic acid has been prepared.Protocatechuic acid lost its carboxylic proton and turned to be protocatechuic anion to form a 1:1:1 organic salt hydrate wit... A drug-drug molecular salt hydrate of berberine and protocatechuic acid has been prepared.Protocatechuic acid lost its carboxylic proton and turned to be protocatechuic anion to form a 1:1:1 organic salt hydrate with berberine,[C(20)H(18)NO4]+[C7H5O4]^-·H2O(1).Compound1 crystallizes in the triclinic system,space group P1 with a = 7.9849(5),b =10.5437(5),c = 14.3621(5)?,α = 77.983(4),β = 82.900(4),γ = 78.024(4)o,V = 1152.82(10) A^3,Mr= 507.48,Dc= 1.462 g/cm^3,μ = 0.929 mm^-1,F(000) = 532,Z = 2,the final R = 0.0488 and w R = 0.1322 for 3993 reflectionswith I 〉 2σ(I).The hydrate exhibited good solid state stability against humidity,which may result from strong hydrogen-bonding interactions between water molecules and carboxylate groups.The hydrate also exhibited acceptable solubility and dissolution rate. 展开更多
关键词 berberine protocatechuic acid molecular salt hydrate non-hygroscopic
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Novel Perchlorate and Sulphate Salts of 2-Aminonicotinic Acid:Synthesis,Characterization,Thermal Studies and Hirshfeld Surface Analysis 被引量:1
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作者 马玉恒 葛书旺 +1 位作者 沈亚 孙柏旺 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第1期7-15,共9页
Since 2-aminonicotinic acid is a zwitterionic molecule,the salt or co-crystal strategy was used for the precipitation under identical conditions and obtained two novel salts: salt 1 with 2:1:2 stoichiometry of 2-am... Since 2-aminonicotinic acid is a zwitterionic molecule,the salt or co-crystal strategy was used for the precipitation under identical conditions and obtained two novel salts: salt 1 with 2:1:2 stoichiometry of 2-aminonicotinic acid:perchloric acid:H2O and salt 2 with 2:1:3 stoichiometry of 2-aminonicotinic acid:sulfuric acid:H2O. Their crystal structures were characterized by single-crystal X-ray diffraction,differential scanning calorimetry(DSC) and thermogravimetric analyses(TGA). The structure determination shows that two salts are both primarily stabilized by the strong N–H…O hydrogen bonding interaction between 2-aminonicotinic acid and its corresponding acids. Constituents of the salt-crystalline phase were also investigated in terms of Hirshfeld surfaces. In the crystal lattice,a three-dimensional hydrogen-bonded network is observed,including the formation of a two-dimensional molecular scaffolding motif. Hirshfeld surfaces and fingerprint plots of two salts show that the structures are stabilized by H…H,O–H…O and C–O…π intermolecular interactions. 展开更多
关键词 2-aminonicotinic acid salt X-ray diffraction Hirshfeld surfaces
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Photodynamic Therapy of Cancer Cells with Methanesulfonate Salts of 5-Aminolevulinic Acid and Its Derivatives
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作者 QIU Xue-peng KOSOBE Toshiyuki KAWASHIMA Norimichi 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2010年第1期66-69,共4页
A series of 5-aminolevulinic acid and its alkylester methanesulfonates was exploited to photodynamic therapy(PDT) of human lymphocytic cells, U-937 in vitro. The PDT efficiency is influenced by the concentration and... A series of 5-aminolevulinic acid and its alkylester methanesulfonates was exploited to photodynamic therapy(PDT) of human lymphocytic cells, U-937 in vitro. The PDT efficiency is influenced by the concentration and incubation time. Generally, for ALA and its alkylester methanesulfonates, the cell survival rate decreases and the accumulation ability of PplX increases with the concentration and incubation time. We found that the longer carbon chain methanesulfonates(C5-S, C6-S, C8-S) exhibit better PDT effect than ALA methanesulfonate. This possibly provides a promising route to the clinical application ofPplX-mediated PDT to cancer cell. 展开更多
关键词 Photodynamic therapy Methanesulfonate salt 5-Aminolevulinic acid DERIVATIVE Cancer cell
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Effect of Acid and Alkali Stress on Seed Germination and Seedling Growth of Caragana versicolor
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作者 Ge Qingsong Wang Hang +1 位作者 Gao Yi Fang Jiangping 《Animal Husbandry and Feed Science》 CAS 2019年第2期45-48,共4页
With seeds of Caragana versicolor in Purang County, Tibet as the materials, the seed germination and seedling growth of C. versicolor were measured under acid and alkali stress, and the soil acidity and alkalinity for... With seeds of Caragana versicolor in Purang County, Tibet as the materials, the seed germination and seedling growth of C. versicolor were measured under acid and alkali stress, and the soil acidity and alkalinity for normal growth and development of C. versicolor were determined, so as to provide the theoretical basis for cultivation of C. versicolor in acidified or alkaline soil. The results showed that the seed germination of C. versicolor was promoted when treated by strong acid (pH 3) and strong alkali (pH 11) solutions, and the seedling effect was good. The results also indicated that C. versicolor was a kind of plant with strong acid and alkali resistance, suitable for cultivation in acid and alkali soil areas. 展开更多
关键词 Tibet CARAGANA VERSICOLOR acid and alkali stress Seed germination SEEDLING growth
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Feeding Calcium Salts of Linseed Oil on Productive Performance and Milk Fatty Acid Profile in Grazing Dairy Cows
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作者 Yaliska Moreno González Jesica Iorio +7 位作者 María Florencia Olmeda Dino Curletto Daniel Scandolo Martín Guillermo Maciel Alejandra Cuatrin Rafael Alejandro Palladino Carolina Pérez Eloy Eduardo Salado 《Open Journal of Animal Sciences》 2020年第4期761-781,共21页
The objective of this study was to determine the effect of supplying calcium salts of linseed oil (Ca-FA) rich in omega-3 (α-linolenic acid) on the production and chemical composition of milk and its nutraceutical va... The objective of this study was to determine the effect of supplying calcium salts of linseed oil (Ca-FA) rich in omega-3 (α-linolenic acid) on the production and chemical composition of milk and its nutraceutical value in dairy cows in early lactation. The trial lasted 12 weeks (2 weeks for adaptation to lipids and 10 weeks of data collection). A total of 36 Holstein dairy cows with 58.0 ± 17.0 days in milk (DIM), 594.1 ± 92.4 kg BW, 2.6 ± 1.5 parity and 38.9 ± 9.3 kg milk day<sup>-1</sup> were used in a randomized complete block design. The treatments were: 1) Omega-3 (O3): 5.2 kg DM day<span style="font-size:10px;white-space:normal;"><sup>-1</sup></span> of concentrate including 0.7 kg DM of Ca-FA + 13.5 kg DM <span style="white-space:normal;">day</span><span style="font-size:10px;white-space:normal;"><sup>-1</sup></span> of partial mixed ration (PMR) + 12 kg DM <span style="white-space:normal;">day</span><span style="font-size:10px;white-space:normal;"><sup>-1</sup></span> of alfalfa pasture (Medicago sativa) and 2) Control (C): diet similar to O3 but lipid supplementation was replaced by cracked corn grain so that the diets were isoenergetic. No treatment effect was detected (P > 0.05) for any milk production and composition variables, except for urea in milk that was slightly higher in O3 (P = 0.02). The treatment × week interaction was significant (P < 0.05) for fat yield and content, with differences (P < 0.01) only in the 3rd week of the data collection period in favor of group C (1.39 vs. 1.13 kg<span style="font-family:Verdana, Helvetica, Arial;white-space:normal;background-color:#FFFFFF;">&#183;</span><span style="white-space:normal;">day</span><span style="font-size:10px;white-space:normal;"><sup>-1</sup></span> and 3.86% vs. 3.23% for fat yield and content, respectively). Total DMI and PMR were similar (P > 0.05) between treatments. Concentrate intake was higher (P < 0.01) in C compared with O3. Pasture DMI tended (P = 0.06) to be greater for cows that received the O3 treatment compared with C. Total metabolizable energy (ME) intake was similar (P = 0.44) between treatments. No treatment effect was detected (P > 0.05) in rumen environment parameters. Supplementation with Ca-FA reduced (P < 0.05) the hypercholesterolemic fraction of milk (C12:0, C14:0 and C16:0, -13.6%, -7.4% and -9.0%, respectively). The concentration of α-linolenic acid (C<sub>18:3n-3</sub>) increased (108%, P < 0.01) in O3 group compared with group C. The absence of negative effects of lipids on the fat content of milk and ruminal fermentation suggests that protection by saponification was effective. The supplementation with Ca-FA (0.85 <span style="white-space:normal;">kg</span><span style="white-space:normal;font-family:Verdana, Helvetica, Arial;background-color:#FFFFFF;">&#183;</span><span style="white-space:normal;">day</span><span style="font-size:10px;white-space:normal;"><sup>-1</sup></span>) improved the healthy value of the milk. 展开更多
关键词 Dairy Cow Calcium salts of Linseed Oil α-Linolenic acid Nutraceutical Value
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Synthesis and Crystal Structure Analysis of 2-(3,5-Di-tert-butyl-2-hydroxyphenyl)-2-(3,4- dimethylphenyl) Acetic Acid Dimethylamine Salt
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作者 程杰 成昌梅 +3 位作者 何娟 尚培华 王如骥 赵玉芬 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第4期414-418,共5页
A new compound 2-(3,5-di-tert-butyl-2-hydroxyphenyl)-2-(3,4-dimethylphenyl) acetic acid dimethylamine salt ([NH2(CH3)2][C24H31O3]) was synthesized and structurally determined. It is of monoclinic system, space... A new compound 2-(3,5-di-tert-butyl-2-hydroxyphenyl)-2-(3,4-dimethylphenyl) acetic acid dimethylamine salt ([NH2(CH3)2][C24H31O3]) was synthesized and structurally determined. It is of monoclinic system, space group P21/c with a = 14.731(2), b = 10.1185(10), c = 17.065(2) A^°, β = 98.293(10)° ,Z = 4, V = 2517.0(6)A^°^3, Dc = 1.091 g/cm^3, F(000) = 904 and Mr= 413.58. The dihedral angle defined by two benzene rings is 98.23°. 展开更多
关键词 2-(3 5-di-tcrt-butyl-2-hydraxyphenyl)-2-(3 4-dimethylphenyl) acetic acid dimethylamine salt synthesis X-ray diffraction crystal structure
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Bifunctional Mn-doped CoSe_(2) nanonetworks electrode for hybrid alkali/acid electrolytic H_(2) generation and glycerol upgrading
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作者 Linfeng Fan Yaxin Ji +5 位作者 Genxiang Wang Zhifang Zhang Luocai Yi Kai Chen Xi Liu Zhenhai Wen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第9期424-431,I0012,共9页
Electrolytic water splitting,as a promising route to hydrogen(H_(2))production,is still confronted with the sluggish anodic oxygen evolution reaction(OER)and its less value-added O2 production.Herein,we report a bifun... Electrolytic water splitting,as a promising route to hydrogen(H_(2))production,is still confronted with the sluggish anodic oxygen evolution reaction(OER)and its less value-added O2 production.Herein,we report a bifunctional electrode fabricated by in situ growth of Mn-doped CoSe_(2)nanonetworks on carbon fiber cloth(Mn-CoSe_(2)/CFC),which shows attractive electrocatalytic properties toward glycerol oxidation reaction(GOR)in alkali and hydrogen evolution reaction(HER)in acid.A flow alkali/acid hybrid electrolytic cell(fA/A-hEC)was then developed by coupling anodic GOR with cathodic HER with the Mn-CoSe_(2)/CFC bifunctional electrode.Such fA/A-hEC enables a rather low voltage of 0.54 V to achieve 10 mA cm^(-2),and maintain long-term electrolysis stability over 300-h operation at 100 mA cm^(-2)with Faraday efficiencies of over 99%for H_(2)and 90%for formate production.The designed bifunctional electrode in such innovative fA/A-hEC device provides insightful guidance for coupling energy-efficient hydrogen production with biomass upgradation. 展开更多
关键词 Mn-doped CoSe_(2)nanonetworks Glycerol upgrading electrooxidation Hydrogen production Bifunctional electrocatalytic electrode Hybrid flow alkali/acid electrolyzer
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Swelling Properties of New Hydrogels Based on the Dimethyl Amino Ethyl Acrylate Methyl Chloride Quaternary Salt with Acrylic Acid and 2-Methylene Butane-1,4-Dioic Acid Monomers in Aqueous Solutions
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作者 Issa Katime Eduardo Mendizábal 《Materials Sciences and Applications》 2010年第3期162-167,共6页
Hydrogels of dimethylaminoethyl acrylate methyl chloride quaternary salt (Q9) have been synthesized with different monomer ratio by copolymerization of this poorly studied monomer either with acrylic acid or with 2-me... Hydrogels of dimethylaminoethyl acrylate methyl chloride quaternary salt (Q9) have been synthesized with different monomer ratio by copolymerization of this poorly studied monomer either with acrylic acid or with 2-methylene bu-tane-1,4-dioic acid. Hydrogel swelling was measured as a function of the composition of the hydrogel and of the crosslinking agent ratio. High values of swelling have been obtained at very high crosslinking values (【14 wt %) and the equilibrium swelling was reached at very low time (less than 15 minutes). The swelling isotherms consisted of a steep initial portion and then levelled off as asymptotically to the equilibrium swelling limit. The experimental data suggest clearly that the swelling process obeys second-order kinetics. According to this, the kinetics rate constant and the equilibrium water content were determined at different comonomer composition and crosslinker concentration. The calculated kinetic constants ranged from 0.48 to 3.76 &#215;10-2 min-1 for poly (acrylic acid-co-Q9) hydrogels and from 0.68 to 4.0 &#215;10-2 min-1 for poly (2-methylene butane-1,4-dioic acid-co-Q9) hydrogels depending on the hydrogels composition. The diffusion process was evaluated for each hydrogel showing a non-Fickian type diffusion. In all cases was observed a considerable increase in diffusion coefficient as Q9 content increases. 展开更多
关键词 DIMETHYL Amino Ethyl Acrylate Methyl Chloride QUATERNARY salt 2-methylene butane-1 4-Dioic acid Acrylic acid SWELLING Diffusion Coefficients Kinetic Order
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Influence of Neutral Salts and pH on Exchangeable Acidity of Red Soil and Latosol Colloids 被引量:2
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作者 ZHOU SHIWEI, ZHANG GANGYA and ZHANG XIAONIAN Institute of Soil Science, the Chinese Academy of Sciences, Nanjing 210008 (China) 《Pedosphere》 SCIE CAS CSCD 2002年第1期81-88,共8页
In the present work, the exchangeable acidity of a red soil colloid and a latosol colloid at different pH during reacting with four neutral salts was measured. The results show that the exchangeable acidity increased ... In the present work, the exchangeable acidity of a red soil colloid and a latosol colloid at different pH during reacting with four neutral salts was measured. The results show that the exchangeable acidity increased with increasing amounts of the neutral salts added, and the relation between them was almost linear. When the amount of the neutral salt added was lower than a certain value, the slope of the line was high, and the slope turned low when the amount exceeded that value, so there was a turning point in each line. The addition amounts of the neutral salts for the turning points were affected by the cation species of the neutral salts, but pH had less effect on them. After the turning points occurred, the exchangeable acidity of the red soil colloid still gradually increased with the addition amounts of the neutral salts, but that of the latosol colloid did not increase any more. The exchangeable acidity in NaClO4, KClO4 and NaCl solutions increased at first, and then decreased with increasing pH, that is to say, peak values appeared. The peak positions of the exchangeable acidity in relation to pH changed with neutral salt solutions and were affected by the surface characteristics of the soil colloids, but not affected by the amounts of the neutral salts added. The exchangeable acidity in the Ba(NO3)2 solution increased continuously with increasing pH. The exchangeable acidity of the red soil colloid was obviously larger than that of the latosol colloid. 展开更多
关键词 红壤 淋滤土 胶体 PH 中性盐 土壤酸度
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Salt Effect on the Liquid-Liquid Equilibrium of (Water + Propionic Acid + Cyclohexanol) System at T=(298.2,303.2,and 308.2) K 被引量:1
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作者 Bahram Ghalami-Choobar Ali Ghanadzadeh and Shahram Kousarimehr 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2011年第4期565-569,共5页
Effects of salt and temperature on the liquid phase equilibrium of the(water + propionic acid + cyclohexanol) system were investigated.The liquid-liquid equilibrium data in the presence of KCl for various salt ionic s... Effects of salt and temperature on the liquid phase equilibrium of the(water + propionic acid + cyclohexanol) system were investigated.The liquid-liquid equilibrium data in the presence of KCl for various salt ionic strength of 0.5,1.0,1.5,2.0,and 2.5 mol·dm3 and in absence of the salt at T=(298.2,303.2,and 308.2)K were determined.The experimental results were correlated based on the Othmer-Tobias equation and Pitzer ion-interaction model.Thermodynamic properties such as distribution coefficients and activity coefficients of propionic acid in water + cyclohexanol were determined.In addition,the separation factor,S,of the chosen solvent was obtained for the investigated system. 展开更多
关键词 液液平衡 盐效应 环己醇 系统 酸水 丙酸 离子相互作用 热力学性质
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Physiological Mechanism of Salicylic Acid for Alleviation of Salt Stress in Rice 被引量:11
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作者 D.JINI B.JOSEPH 《Rice science》 SCIE CSCD 2017年第2期97-108,共12页
Soil salinity is one of the most important problems of crop production in estuarine and coastal zones. Improvement in salt tolerance of major food crops is an important way for the economic utilization of coastal zone... Soil salinity is one of the most important problems of crop production in estuarine and coastal zones. Improvement in salt tolerance of major food crops is an important way for the economic utilization of coastal zones. This study proved that the application of salicylic acid(SA) improved the growth and yield under salt stress conditions and investigated its physiological mechanisms for salt tolerance. The investigation on the effect of SA for salt tolerance during germination showed that the decreased rates of germination and growth(in terms of shoot and root lengths) by the salt stress were significantly increased by the SA application(SA + NaCl). The treatment of SA to the high and low saline soils enhanced the growth, yield and nutrient values of rice. The effects of SA on Na^+, K^+ and Cl~– ionic accumulation were traced under salt stress condition by inductively coupled plasma optical emission spectrometry and ion chromatography. It was revealed that the increased accumulation of Na^+ and Clˉ ions by the salt stress were reduced by SA application. An increased concentration of endogenous SA level was detected from the SA-treated rice varieties(ASD16 and BR26) by liquid chromatography electrospray Ionization-tandem mass spectrometry. The activities of antioxidant enzymes such as superoxide dismutase, catalase and peroxidase were increased by salt stress whereas decreased by the SA application. The study proved that the application of SA could alleviate the adverse effects of salt stress by the regulation of physiological mechanism in rice plants. In spite of salt stress, it can be applied to the coastal and estuarine regions to increase the rice production. 展开更多
关键词 salicylic acid salt tolerance ORYZA SATIVA NaCl GERMINATION PHYSIOLOGY
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Effects of Cinnamic Acid on Bacterial Community Diversity in Rhizosphere Soil of Cucumber Seedlings Under Salt Stress 被引量:9
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作者 LIU Jing WU Feng-zhi YANG Yang 《Agricultural Sciences in China》 CAS CSCD 2010年第2期266-274,共9页
To investigate the effects of a plant autotoxin, cinnamic acid, on bacterial communities in the rhizosphere soil of cucumber seedlings under salt stress, we used cucumber as the experimental material, cinnamic acid as... To investigate the effects of a plant autotoxin, cinnamic acid, on bacterial communities in the rhizosphere soil of cucumber seedlings under salt stress, we used cucumber as the experimental material, cinnamic acid as the autotoxin, and NaCl to apply salt stress. Bacterial communities in the rhizosphere soil were analyzed using polymerase chain reaction (PCR), denaturing gradient gel electrophoresis (DGGE), and clone sequencing. Salt stress decreased the diversity of bacterial species in rhizosphere soil of cucumber seedlings at several growth stages. Cinnamic acid exacerbated the effects of salt stress at high concentrations, but alleviated its effects at low concentrations. Cloning and sequencing results indicated that DGGE bands amplified from soil samples showed high homology to uncultured bacterial species. Cinnamic acid at 50 mg kg^-1 soil improved cucumber growth and was the most effective treatment to alleviate the effects of salt stress on bacterial communities. 展开更多
关键词 BACTERIA cinnamic acid CUCUMBER salt stress PCR-DGGE
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Reductive smelting of spent lead–acid battery colloid sludge in a molten Na_2CO_3 salt 被引量:8
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作者 Yu-jie Hu Chao-bo Tang +1 位作者 Mo-tang Tang Yong-ming Chen 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2015年第8期798-803,共6页
Lead extraction from spent lead–acid battery paste in a molten Na2CO3 salt containing Zn O as a sulfur-fixing agent was studied. Some influencing factors, including smelting temperature, reaction time, Zn O and salt ... Lead extraction from spent lead–acid battery paste in a molten Na2CO3 salt containing Zn O as a sulfur-fixing agent was studied. Some influencing factors, including smelting temperature, reaction time, Zn O and salt dosages, were investigated in detail using single-factor experiments. The optimum conditions were determined as follows: T = 880°C; t = 60 min; Na2CO3/paste mass ratio = 2.8:1; and the Zn O dosage is equal to the stoichiometric requirement. Under the optimum conditions, the direct recovery rate of lead reached 98.14%. The results suggested that increases in temperature and salt dosage improved the direct recovery rate of lead. XRD results and thermodynamic calculations indicated that the reaction approaches of lead and sulfur were Pb SO4→Pb and Pb SO4→Zn S, respectively. Sulfur was fixed in the form of Zn S, whereas the molten salt did not react with other components, serving only as a reaction medium. 展开更多
关键词 lead–acid batteries molten salts lead smelting des
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