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Effects of Microencapsulated Compound Acidifier on Acidity and Development of Gastrointestinal Tract in Weaning Piglets 被引量:4
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作者 JIA Gang YAN Jia-you WANG Kang-ning 《Animal Husbandry and Feed Science》 CAS 2009年第6期34-37,共4页
The effects of different types of compound acidifiers (encapsulated and non-encapsulated) in maize-soybean basic diets on acidity and development of the gastrointestinal tract in weaning piglets were investigated in... The effects of different types of compound acidifiers (encapsulated and non-encapsulated) in maize-soybean basic diets on acidity and development of the gastrointestinal tract in weaning piglets were investigated in this study. 64 28-day-old weaned Landrace x Yorkshire hybrid piglets with average weight of (7.00 ±0.10) kg were selected and grouped into four treatments with four pigs ( half boars and half sows) in each repeat of four repeats in each treatment based on single-factor test design principles, and the pre-test period was 3 days but the test period was 35 days. The results showed that compared with acid-free diet group, encapsulated compound acidifier could reduce pH of stomach and intestinal in weaning piglets significantly (P 〈 0.01 ), while Test group 1 could also increase the relative weight of stomach and intestinal in piglets significantly (P 〈 0.05 ). Compared with non-encapsulated acidifier, encapsulated compound acidifier could greatly decrease pH in jejunum and ileum of weaning piglets ( P 〈 0.05) or relative weight of stomach in piglets ( P〈0.05), while Test group 1 could also enhance the relative weight of intestinal in piglets significantly ( P 〈0.01 ). In addition, encapsulated compound acidifiers significantly increased the ratio between the villus height and crypt depth of jejunum ( P 〈0.01 ). Accordingly, the microencapsulated compound acidifier in diets of weaning piglets can promote the development of gastrointestinal tracts for piglets by reducing pH of gastrointestinal tracts. 展开更多
关键词 Microencapsulated compound acidifier Weaning piglet Digestive tract acidity Digestive tract development
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Preparation of lactic acid bacteria compound starter cultures based on pasting properties and its improvement of glutinous rice flour and dough 被引量:1
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作者 Dengyu Wang Linlin Liu +4 位作者 Bing Wang Wenjian Xie Yanguo Shi Na Zhang Hongchen Fan 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第4期2090-2101,共12页
The effects of 5 lactic acid bacteria(LAB)fermentation on the pasting properties of glutinous rice flour were compared,and suitable fermentation strains were selected based on the changes of viscosity,setback value,an... The effects of 5 lactic acid bacteria(LAB)fermentation on the pasting properties of glutinous rice flour were compared,and suitable fermentation strains were selected based on the changes of viscosity,setback value,and breakdown value to prepare LAB compound starter cultures.The results revealed that Latilactobacillus sakei HSD004 and Lacticaseibacillus rhamnosus HSD005 had apparent advantages in increasing the viscosity and reducing the setback and breakdown values of glutinous rice flour.In particular,the compound starter created using the two abovementioned LAB in the ratio of 3:1 had better performance than that using a single LAB in improving the pasting properties and increasing the water and oil absorption capacity of glutinous rice flour.Moreover,the gelatinization enthalpy of the fermented samples increased significantly.For frozen glutinous rice dough stored for 28 days,the viscoelasticity of frozen dough prepared by compound starter was better than that of control dough,and the freezable water content was lower than that of control dough.These results indicate that compound LAB fermentation is a promising technology in the glutinous rice-based food processing industry,which has significance for its application. 展开更多
关键词 Glutinous rice flour Glutinous rice dough Lactic acid bacteria compound starter cultures Pasting properties VISCOELASTICITY
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The Condensation of Aromatic Aldehydes with Acidic Methylene Compounds in Water 被引量:2
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作者 DaQingSHI JingCHEN +2 位作者 QiYaZHUANG XiangShanWANG HongWenHU 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第12期1242-1245,共4页
The condensation of aromatic aldehydes with acidic methylene compounds such as malononitrile, methyl cyanoacetate, cyanoacetamide, 5,5-dimethyl-1,3-cyclohexanedione, bartbituric acid and 2-thiobarbituric acid proceede... The condensation of aromatic aldehydes with acidic methylene compounds such as malononitrile, methyl cyanoacetate, cyanoacetamide, 5,5-dimethyl-1,3-cyclohexanedione, bartbituric acid and 2-thiobarbituric acid proceeded very efficiently in water in the presence of triethylbenzylammonium chloride (TEBA) and the products were isolated simply by filtration. 展开更多
关键词 CONDENSATION aromatic aldehyde acidic methylene compound WATER green chemistry.
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Synthesis and Evaluation of Nicotinoylamino Acid Compounds as Radiosensitizer 被引量:1
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作者 QIN Zhi-zhong ZHANG Feng-bao +3 位作者 JIANG Tie-nan LI Mei-jia WANG Rong-xian LI Yi-liang 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2008年第4期496-500,共5页
Nicotinoylamino acid compounds 4, 5, 9a, 9b, 9c, 10a and 10b were synthesized with nicotinoyl chloride or nicotinoyl azide as acetylating agents of amino acid esters or amino acids. The compounds were tested for their... Nicotinoylamino acid compounds 4, 5, 9a, 9b, 9c, 10a and 10b were synthesized with nicotinoyl chloride or nicotinoyl azide as acetylating agents of amino acid esters or amino acids. The compounds were tested for their radiosensitizing activity in Leukemia cell line(L1210) and compared with nicotinamide; among them, compounds 9a and 9c showed significant radiosensitizing effects, the sensitizer enhancement ratio(SER) was 1.64 and 1.58, respectively, while nicotinamide did not show good radiosensitizing effect under the same conditions. Compound 9c was alone tested for radiosensitization in LA 795 cell-bearing T-739 mice, or hyperthermia and breathing carbogen(5%CO2+95%O2) were together tested for radiosensitization. The results showed that radiation-induced growth delay was enhanced by 9c alone or by the combination of hypertheimia and carbogen. The tumor-bearing mice were irradiated locally by total 10 Gy, and the tumors grew to three times that of the original volume in an average of 5.8 d. The mice were given i.p. compound 9c at 1000 mg/kg 60 min before irradiation and treated at 43 ℃ for 30 min after irradiation or treated with breathing carbogen for 5 min before radiation or with hyperthmia(43 ℃) for 30 min after irradiation; the time required for the tumor to grow to three times the orginal volume was in an average of 12.9 and 13 d, respectively. 展开更多
关键词 RADIOSENSITIZER Nicotinoylamino acid compound HYPERTHERMIA CARBOGEN
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Evaluation of Protein Concentration, Amino Acid Profile and Antinutritional Compounds in Hempseed Meal from Dioecious and Monoecious Varieties 被引量:8
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作者 Roberto Russo Remo Reggiani 《American Journal of Plant Sciences》 2015年第1期14-22,共9页
Hempseed meal from three dioecious and three monoecious varieties has been evaluated for content and quality of the protein and for the concentration of antinutritional compounds. Hemp seeds were obtained from plants ... Hempseed meal from three dioecious and three monoecious varieties has been evaluated for content and quality of the protein and for the concentration of antinutritional compounds. Hemp seeds were obtained from plants grown in two experimental fields for two consecutive years (2011-2012). For all the varieties, hempseed meal resulted in a rich source of protein (34% mean content) with an amino acid profile extremely rich in arginine and slightly poor in lysine. Differences between dioecious and monoecious varieties were observed in the content of antinutritional compounds. They were more concentrated in monoecious varieties in comparison with those dioecious. The concentration of phytic acid in hempseed meal deserves attention in both groups, being 63 and 75.4 g·kg-1 of dry matter in dioecious and monocieous varieties, respectively. The results show that, besides the recognized value of hemp oil, also the hempseed cake could find application in animal feed as a substitute of other cakes (soybean, rapeseed). From this point of view, the dioecious varieties showing lower contents of antinutritional compounds with respect to the monoecious varieties would be preferred. 展开更多
关键词 ANTINUTRITIONAL compoundS AMINO acid Profile DIOECIOUS MONOECIOUS Protein
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Duration of treatment with 5-aminosalicylic acid compounds 被引量:1
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作者 T Moshkovska JF Mayberry 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第32期4310-4315,共6页
The development of 5-aminosalicylic acid (5-ASA) therapy as a life long treatment for ulcerative colitis is reviewed from its origins in the 1940s to the present day. The drug was designed to treat rheumatoid arthriti... The development of 5-aminosalicylic acid (5-ASA) therapy as a life long treatment for ulcerative colitis is reviewed from its origins in the 1940s to the present day. The drug was designed to treat rheumatoid arthritis,but was found helpful in the management of nine patients with ulcerative colitis. This discovery preceded the emergence of the clinical trial as a tool for assessing a new drug's efficacy; as a result it lacked scientific rigour and was selective in its presentation of results. Nevertheless it identified the future cornerstone of therapy in ulcerative colitis. In 1962,the first double blind controlled trial of sulphasalazine was conducted on 40 patients. Outcome measures were subjective and included symptoms and an assessment of the rectal mucosa. In 1973,the first two papers on the role of sulphasalazine in maintenance of remission were published. Both used placebo controls and had a stratified design. Outcomes were measured using "an intention to treat" approach. The British study of 64 patients used both subjective and objective criteria to assess outcomes. Patients on placebo had a relapse rate four times patients on active treatment and this founded the basis for a life long approach to therapy with 5-ASA compounds in ulcerative colitis. However,in 1985,a small "on demand" study of 32 patients suggested this approach might be as effective as continuous treatment. Some support for this view came from an Italian study which showed no benefit to continued treatment for those in remission for two years or more. The central problem these studies identify is that of adherence to treatment in the long-term. Few studies have considered patients' attitudes to continuous therapy and it is an area that needs further investigation. 展开更多
关键词 Ulcerative colitis 5-aminosalicylic acid compounds Sulphasalazine mesalazine adherance trials
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Efficiency of Chalcone Compounds Inhibitors for Acid Corrosion of Al and Al-3.5Mg Alloy 被引量:1
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作者 I. Z. Selim A. A. Khedr and K.M.EI-Sobki(Physical Chemistry Dept., National Research Centre, Dokki, Cairo, Egypt) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1996年第4期267-272,共6页
Corrosion inhibition of Al and Al-3.5Mg alloy by organic compounds, namely chalcones in hydrochloric acid solutions has been investigated by rapid polarization technique and weight loss method. Polarization measuremen... Corrosion inhibition of Al and Al-3.5Mg alloy by organic compounds, namely chalcones in hydrochloric acid solutions has been investigated by rapid polarization technique and weight loss method. Polarization measurements show that, the inhibitors act cathodically both in case of Al and Al-3.5Mg alloy. It was found from the weight loss measurements that, the inhibition efficiency depends on the substituent in the chalcone compound. The relative inhibitive efficiency of these compounds has been explained on the basis of structure dependent electron donor properties of the inhibitors and the metal inhibitor interaction on the surface. The inhibition efficiency ranges from 16 to 64% for Al and from 30% to 91% for Al-3.5Mg alloy 展开更多
关键词 AL Efficiency of Chalcone compounds Inhibitors for acid Corrosion of Al and Al-3.5Mg Alloy
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Analysis of the Fatty Acids and Phenolic Compounds in a Cereal-Based Fermented Food (Tarhana) 被引量:1
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作者 Maribel Ovando-Martinez Orhan Daglioglu +1 位作者 Umit Gecgel Senay Simsek 《Food and Nutrition Sciences》 2014年第13期1177-1184,共8页
Tarhana is a Turkish home-made fermented food product. The mixture of wheat flour, yoghurt, yeast, cooked vegetables, salt, and spices is fermented for 1 - 7 days. Tarhana is sun dried and ground for preparation of in... Tarhana is a Turkish home-made fermented food product. The mixture of wheat flour, yoghurt, yeast, cooked vegetables, salt, and spices is fermented for 1 - 7 days. Tarhana is sun dried and ground for preparation of instant Tarhana powder. Color, phenolic compounds and fatty acid composition were determined for home-made Tarhana, collected from 4 cities in the Thrace Region of Turkey. Color and phenolic content were significantly different (P < 0.05). These differences were due to the variation of ingredients used at different locations. The major unsaturated fatty acids were oleic (C18:1, 16.41% - 57.69%), and linoleic acids (C18:2, 9.74% - 56.31%). Palmitic (C16:0, 16.90% - 37.66%) and stearic acids (C18:0, 0.65% - 11.34%) were the main saturated fatty acids. This study suggested that Tarhana soup is a good source of unsaturated fatty acids. Antioxidant properties of phenolic compounds and their effect on peroxidation of lipids in Tarhana should be tested in future studies. 展开更多
关键词 Tarhana PHENOLIC compoundS FATTY acid COMPOSITION
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Syntheses, Crystal Structures, Magnetic and Luminescent Properties of Ni(Ⅱ), Cd(Ⅱ) and Pb(Ⅱ) Coordination Compounds Constructed from 5-Fluoronicotinic Acid 被引量:1
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作者 LI Yu ZOU Xun-Zhong +2 位作者 QIU Wen-Da FENG An-Sheng CHEN Xiao-Ling 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2019年第6期999-1011,共13页
Five coordination compounds, namely [Ni2(5-Fnic)2(H2 O)4](1), [Ni(5-Fnic)(μ-5-Fnic)(H2 biim)]n(2), {[Cd((μ-5-Fnic)2(H2 O)2]×4,4’-bipy}n(3), [Pb2(μ-5-Fnic)2(μ3-5-Fnic)2(H2 O)2]n(4), and [Pb(5-Fnic)2(4,4’-bip... Five coordination compounds, namely [Ni2(5-Fnic)2(H2 O)4](1), [Ni(5-Fnic)(μ-5-Fnic)(H2 biim)]n(2), {[Cd((μ-5-Fnic)2(H2 O)2]×4,4’-bipy}n(3), [Pb2(μ-5-Fnic)2(μ3-5-Fnic)2(H2 O)2]n(4), and [Pb(5-Fnic)2(4,4’-bipy)(H2 O)](5), have been constructed hydrothermally using 5-FnicH(5-FnicH = 5-fluoronicotinic acid), H2 biim(H2 biim = 2,2’-biimidazole), 4,4’-bipy(4,4’-bipy = 4,4’-bipyridine), NiCl2×6 H2 O, CdCl2×H2 O and PbCl2. The products were isolated as stable crystalline solids and were characterized by IR spectra, elemental analyses, thermogravimetric analyses(TGA), and single-crystal X-ray diffraction analyses. Structures of 1~5 range from discrete 0 D monomers(1 and 5) to 1 D coordination polymers(2 and 4) and 2 D metal-organic network(3). A broad structural diversity of 1~5 is guided by the type of the metal(Ⅱ) node and the introduction of auxiliary ligands. The magnetic(for 2) and luminescent(for 3~5) properties were also investigated and discussed. 展开更多
关键词 coordination compound 5-fluoronicotinic acid MAGNETIC properties luminescent PROPERTIES
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Syntheses, Crystal Structures and Luminescent and Magnetic Properties of Cerium(Ⅲ) and Zinc(Ⅱ) Coordination Compounds Constructed from 3,5-Dibromobenzoic Acid 被引量:1
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作者 高竹青 李红晋 顾金忠 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第2期227-234,共8页
Two coordination compounds, namely [Ce(3,5-Br2BC)3(3,5-HBrzBC)]n (1) and [Zn(3,5-Br2BC)2(phen)] (2, 3,5-HBr2BC = 3,5-dibromobenzoic acid, phen = 1,10-phenanthroline), were assembled. Single-crystal X-ray d... Two coordination compounds, namely [Ce(3,5-Br2BC)3(3,5-HBrzBC)]n (1) and [Zn(3,5-Br2BC)2(phen)] (2, 3,5-HBr2BC = 3,5-dibromobenzoic acid, phen = 1,10-phenanthroline), were assembled. Single-crystal X-ray diffraction studies show that compound 1 possesses a ID chain coordination network, which is further extended into a 3D supramolecular architecture via Br..'Br and Br'"O halogen bonding. Compound 2 consists of a mononuclear molecule, which is assembled to a 3D supramolecular framework through C-H..-O hydrogen bond, π-π stacking interactions and Br..π halogen bonding. Luminescent and magnetic properties of both compounds have also been studied. 展开更多
关键词 coordination compound 3 5-dibromobenzoic acid luminescent properties magnetic properties
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Synthesis and antitumor activities of structure-related small molecular compounds of gambogic acid 被引量:2
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作者 Nian Guang Li Qi Dong You +5 位作者 Xue Feng Huang Jin Xin Wang Qing Long Guo Xiao Guang Chen Yan Li Hong Yan Li 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第6期659-662,共4页
Through simplifying the complicated skeleton of the natural product gambogic acid, two series derivatives of chromone and xanthone were synthesized and examined for their antitumor activities against several cancer ce... Through simplifying the complicated skeleton of the natural product gambogic acid, two series derivatives of chromone and xanthone were synthesized and examined for their antitumor activities against several cancer cells in vitro by MTT method. The results showed that appropriate introduction of prenyl group to the small molecular compounds could elevate their antitumor activities. The structure–activities relationship of synthesized compounds certified that the bridgecore in gambogic acid was very important for keeping its antitumor activities. 展开更多
关键词 Gambogic acid Small molecular compounds Antitumor activity
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Syntheses,Crystal Structures and Antibacterial Activities of 5-Chloro-3-methyl-1-phenyl-1H-pyrazole-4-carboxylic Acid and Its Copper(Ⅱ) Compound 被引量:2
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作者 温辉梁 康静静 +2 位作者 戴兵 邓瑞红 胡海威 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第1期33-40,共8页
The title compounds 5-chloro-3-methyl-1-phenyl-1H-pyrazole-4-carboxylic acid(C11H9Cl N2O2, HL)(1) and [Cu(L)2(H2O)](2) were prepared and structurally characterized by elemental analysis, IR and single-crysta... The title compounds 5-chloro-3-methyl-1-phenyl-1H-pyrazole-4-carboxylic acid(C11H9Cl N2O2, HL)(1) and [Cu(L)2(H2O)](2) were prepared and structurally characterized by elemental analysis, IR and single-crystal X-ray diffraction. Compound 1(C11H9Cl N2O2) crystallizes in the monoclinic system, space group P21/n with a = 7.249(3), b = 20.515(10), c = 7.249(3),β= 96.30°, V = 1071.6(9) ?3, Z = 4, Mr = 236.65, Dc = 1.467 g/cm3, F(000) = 488, GOOF = 1.029, μ= 0.341 mm-1, the final R = 0.0736 and w R = 0.1966 for 1500 observed reflections with I 〉 2σ(I). Compound 2(C22H18Cl2Cu N4O5) crystallizes in the monoclinic system, space group P21/c with a = 7.2931(6), b = 24.548(2), c = 13.2726(11), β= 99.4040(10)°, V = 2344.2(3) ?3, Z = 4, Mr = 552.84, Dc = 1.566 g/cm3, F(000) = 1124, GOOF = 1.050, μ= 1.201 mm-1, the final R = 0.0376 and w R = 0.1000 for 3626 observed reflections with I 〉 2σ(I). 1 and 2 are connected through hydrogen bonding interactions to generate 2D and 3D supramolecular structures, respectively. Moreover, the preliminary antibacterial activities of 1 and 2 against the gram positive bacteria(S. aureus, C. albicans and B. subtilis) and gram negative bacteria(E. coli and P. aeruginosa) have been tested by using the microdilution method, and the results indicate that 2 is more active than 1 against the tested bacteria. 展开更多
关键词 pyrazole carboxylic acid copper compound helix chain crystal structure antibacterial activity
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Melt Synthesis and Characterization of Poly(L-lactic Acid) Chain Linked by Multifunctional Epoxy Compound 被引量:1
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作者 王远亮 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2010年第5期774-779,共6页
High molecular weight(Mw) poly(L-lactic acid)s(PLLAs) were synthesized using multifunctional epoxy compound(Joncryl-ADR4370) as chain extender. The products were characterized by gel permeation chromatography... High molecular weight(Mw) poly(L-lactic acid)s(PLLAs) were synthesized using multifunctional epoxy compound(Joncryl-ADR4370) as chain extender. The products were characterized by gel permeation chromatography(GPC) and spectroscopy(1HNMR and FTIR). The results indicated that the Mw of PLLA increased with the increasing of the ratio of epoxy compound and the extending of reaction time. The highest Mw of PLLA reached 360 000 g/mol when the ratio of epoxy compound was 1.5 wt%. However, the reactants turned to cross-linking when the ratio of epoxy compound was over 1.5 wt%. Differential scanning calorimetry(DSC) measurements demonstrated that the glass transition(Tg) and melting temperatures(Tm) of products increased slightly as the increase of the molecular weight. Analysis of the hydrolytic degradation in vitro showed that the branched PLLA possessed the quicker degradability than that of the linear PLLA. 展开更多
关键词 melt synthesis poly(lactic acid epoxy compound chain extender
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Corrosion inhibition of α,β-unsaturated carbonyl compounds on steel in acid medium 被引量:5
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作者 Gao Jiancun Weng Yongji +2 位作者 Salitanate Feng Li Yue Hong 《Petroleum Science》 SCIE CAS CSCD 2009年第2期201-207,共7页
Corrosion inhibition of three α,β-unsaturated carbonyl compounds on N80 steel at high temperature and in concentrated acid medium was evaluated, and the inhibition mechanism was investigated. The results proved that... Corrosion inhibition of three α,β-unsaturated carbonyl compounds on N80 steel at high temperature and in concentrated acid medium was evaluated, and the inhibition mechanism was investigated. The results proved that both cinnamaldehyde and benzalacetone had an evident anticorrosion effect and could reduce the corrosion of steel effectively in acid medium, α,β-unsaturated carbonyl compounds with a benzene ring structure had good adsorption on steel surface. The experiments proved that polymerization of α,β-unsaturated carbonyl compounds on the steel surface at a high temperature and in concentrated acid medium resulted in a good corrosion inhibiting effect, which was attributed to the structures of α,β-unsaturated carbonyl compounds. 展开更多
关键词 α β-unsaturated carbonyl compounds corrosion inhibitor ADSORPTION oilfield acidizing treatment
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Characteristics of physico-chemical properties, volatile compounds and free fatty acid profiles of commercial set-type Turkish yoghurts 被引量:1
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作者 Zehra Güler Young W. Park 《Open Journal of Animal Sciences》 2011年第1期1-8,共8页
Ten most popular brands of commercial Turkish set-type yoghurts were collected from local retail outlets in Hatay, Turkey for two separate periods, and analyzed for basic nutrients, physico-chemical properties, volati... Ten most popular brands of commercial Turkish set-type yoghurts were collected from local retail outlets in Hatay, Turkey for two separate periods, and analyzed for basic nutrients, physico-chemical properties, volatile aroma compounds and free fatty acid profiles to compare their differences among the yoghurt products. The results showed that there were significant differences (P<0.05, 0.01, or 0.001) and variations in physico-chemical indices, volatile aroma compounds and volatile free fatty acid profiles among the yoghurt brands, which ultimately influence the flavor quality of the product. Acetaldehyde was predominant volatile compound in yoghurts, which followed by acetone, acetoin, diacetyl and ethanol. The level of diacetly was inversely related to titratable acidity, acetaldehyde and ethanoic acid. From ketones with high carbones 2-undecanone and 2-pentadecanone were higher than 2-butanone, 2-nanonane and 2-tridecanone. These ketones are related to fat content of yoghurt. Among short chain free fatty acids, ethanoic (acetic) acid was the most abundant in yoghurts, followed by hexanoic, octanoic and butanoic acids. These differences in detected chemical compositions of volatile compounds and free fatty acids would be applicable to predict flavor, nutritional value, quality control or shelf-life of the commmercial set-type Turkish yoghurts. 展开更多
关键词 TURKISH YOGHURT free FATTY acidS volatile compounds PHYSICO-CHEMICAL properties
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STUDY ON SYNTHESIS,CHARACTERIZATION AND STRUCTURE OF A NEW RARE EARTH COORDINATION COMPOUND WITH BENZOIC ACID
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作者 段治邦 金钟声 +1 位作者 胡宁海 倪嘉缵 《Journal of Rare Earths》 SCIE EI CAS CSCD 1990年第2期81-86,共6页
In this paper,a new rare earth benzoate coordination compound,[TbL_3(HL)(H_2O)]_2 (HL=C_7H_6O_2=benzoic acid) is synthesized and characterized by elemental analysis DTA,TG,DTC,and IR spectra.The title compound crystal... In this paper,a new rare earth benzoate coordination compound,[TbL_3(HL)(H_2O)]_2 (HL=C_7H_6O_2=benzoic acid) is synthesized and characterized by elemental analysis DTA,TG,DTC,and IR spectra.The title compound crystallizes in triclinic,space.group P with a=9.148(1),b=11.460(2), c=13.506(2);α=112.76(1),β=91.83(1),γ=91.99(1)°;Z=1;V=1303.3.The final R factor is 0.0235.The rare earth ion is nine-coordinated to form a distorted monocapped square antiprism. 展开更多
关键词 STUDY ON SYNTHESIS CHARACTERIZATION AND STRUCTURE OF A NEW RARE EARTH COORDINATION compound WITH BENZOIC acid
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CATIONIC RING-OPENING POLYMERIZATION OF TETRAHYDROFURAN WITH KEGGIN-TYPE HETEROPOLYCOMPOUNDS AS SOLID ACID CATALYSTS 被引量:4
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作者 Ahmed Aouissi Salim Salem Al-Deyab Hassan Al-Shehri 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2010年第3期305-310,共6页
Three Keggin-type heteropolyanions, namely H3PMo12O40-13H2O, (NH4)3PMo12O40·4H2O and H3PW12O40·13H2O were prepared and tested in the ring-opening polymerization reaction of tetrahydrofuran. The effects of ... Three Keggin-type heteropolyanions, namely H3PMo12O40-13H2O, (NH4)3PMo12O40·4H2O and H3PW12O40·13H2O were prepared and tested in the ring-opening polymerization reaction of tetrahydrofuran. The effects of the counter-cation (H+, NH4+) and the peripheral atoms (Mo, W) on the polymerization were investigated. It has been found that when the protons of H3PMo12O40·13H2O were replaced by the ammonium cations the polymerization rate decreased dramatically. Whereas, when the peripheral atoms (Mo) were replaced by their homologous (W), the polymerization rate increased twofold. As for the viscosity average molecular weight (My) of polymer products, it was found that the high molecular weight (7930) was obtained by using H3PW12O40·13H2O. The molecular weight (My) obtained by H3PMo12O40·13H2O and (NH4)H3PMo12O40·13H2O was 6470 and 6810, respectively. 展开更多
关键词 TETRAHYDROFURAN Heteropoly compounds Ring opening polymerization Cyclic ether Solid acid
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Compounding Pattern of REE, Clay and Humic Acid in the Weathering Crust of Granites
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作者 陈炳辉 陈志澄 +3 位作者 梁群优 符群策 俞受鋆 张丽洁 《Journal of Rare Earths》 SCIE EI CAS CSCD 1996年第1期47-53,共7页
An anomalous phase containing clays and humic acid was found while extraction humic acid from samples of weathering crust of REE-bearing granites by using 0.1 mol/L NaOH solution.Studied by chemical separation experim... An anomalous phase containing clays and humic acid was found while extraction humic acid from samples of weathering crust of REE-bearing granites by using 0.1 mol/L NaOH solution.Studied by chemical separation experiments,column chromatography,ion-exchange chromatography,infrared spectrum.fluorescence spectrum,polarimicroscopic testing and elemental determination by ultraviolet-visible spectrometer and atomic absorption spectrometer.it was proved to be a compound of humic acid and clays which are connected in the form of bridge by heteronuclearpolynuclear complexing ions formed by cations of RE ̄(5+),Al ̄(3+).Fe ̄(3+) etc.The compounding pattern was further proved by the experiment for compounding humic acid,REE and kaolinite. 展开更多
关键词 REE Clays Humic acid compounding pattern Weathering crust of granites
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Structures and Properties of Two Pb^Ⅱ Compounds and Theoretical Study of 2,4-Oxybis(benzoic acid) 被引量:1
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作者 唐龙 付峰 +2 位作者 王记江 刘启瑞 曹佳 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第10期1479-1486,共8页
Two Pb^Ⅱ coordination polymers [Pb(oba)(2,2′-bipy)]·1.5H2O(1) and [Pb(oba)(phen)](2)(H2oba = 2,4-oxybis(benzoic acid), 2,2′-bipy = 2,2′-bipyridine, phen = 1,10-phenanthroline) were synthesized... Two Pb^Ⅱ coordination polymers [Pb(oba)(2,2′-bipy)]·1.5H2O(1) and [Pb(oba)(phen)](2)(H2oba = 2,4-oxybis(benzoic acid), 2,2′-bipy = 2,2′-bipyridine, phen = 1,10-phenanthroline) were synthesized by hydrothermal reactions and characterized by single-crystal X-ray diffraction, thermogravimetric analyses, IR spectroscopy and elemental analysis. Structures of compounds 1 and 2 are similar. Compounds 1 and 2 show 1D wavy chains, which are further connected through aromatic π-π stacking interactions to expand into 2D wavelike networks. The crystal structure of 2,4-oxybis(benzoic acid) ligand(3) was obtained, and its full geometry optimization was carried out by using DFT methods at the B3LYP/6-31G(d) level. The calculated data show that the bond distances and bond angles were very close to the experimental data. The values of the frontier orbital energies indicate that this configuration is stable. Moreover, the solid-state fluorescence properties of 1-3 have also been investigated. 展开更多
关键词 Pb^Ⅱ compound 2 4-oxybis(benzoic acid fluorescent properties theoretical study
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Compound-specific isotopes of fatty acids as indicators of trophic interactions in the East China Sea ecosystem
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作者 吴莹 王娜 +3 位作者 张经 万瑞景 戴芳群 金显仕 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2016年第5期1085-1096,共12页
The composition and compound-specific isotopes of fatty acids were studied within food webs in the East China Sea.Lipid-normalized stable carbon isotopes of total organic carbon had a good correlation with trophic lev... The composition and compound-specific isotopes of fatty acids were studied within food webs in the East China Sea.Lipid-normalized stable carbon isotopes of total organic carbon had a good correlation with trophic level.Variations in fatty acid compositions among different species were observed but were unclear.Different dietary structures could be traced from molecular isotopes of selected fatty acids in the Shiba shrimp(Matapenaeus joyneri),the coastal mud shrimp(Solenocera crassicomis) and the northern Maoxia shrimp(Acetes chinensis).Both M.joyneri and S.crassicomis are mainly benthos feeders,while A.chinensis is a pelagic species,although they have a similar fatty acid composition.There was a good correlation for isotopes of arachidonic acid(C20:4n6;ARA) and docosahexaenoic acid(C22:6n3;DHA)among pelagic species from higher trophic levels.The isotopic compositions of DHA in benthic species were more negative than those of pelagic species at the same trophic level.The fact that the diet of benthic species contains more degraded items,the carbon isotopes of which are derived from a large biochemical fraction,may be the reason for this variation.A comparative study of benthic and pelagic species demonstrated the different carbon sources in potential food items and the presence of a more complex system at the watersediment interface. 展开更多
关键词 fatty acid compound-specific isotope ratio stable isotope ratio East China Sea
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