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Synthesis,Crystal Structure and Antimicrobial Activity of a New Ternary Copper(Ⅱ) Complex with p-Chlorophenoxyacetic Acid and 2-Amino Benzothiazole 被引量:1
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作者 辜海彬 龙麟 +2 位作者 李萍萍 王利 陈武勇 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第5期676-681,共6页
A novel ternary complex of Cu(pcpa)2(aben)2 (pcpa=p-chlorophenoxyacetic acid anion,aben=2-amino benzothiazole) was synthesized by the reaction of copper acetate,2-amino benzothiazole and p-chlorophenoxyacetic ac... A novel ternary complex of Cu(pcpa)2(aben)2 (pcpa=p-chlorophenoxyacetic acid anion,aben=2-amino benzothiazole) was synthesized by the reaction of copper acetate,2-amino benzothiazole and p-chlorophenoxyacetic acid.Elemental analysis,IR,UV and X-ray single-crystal diffraction were carried out to determine the composition and crystal structure.The crystal crystalli-zes in the monoclinic system,space group C2/c with a=25.795(4),b=7.384(3),c =17.741(6),β=107.47(2)°,C30H24Cl2CuN4O6S2,Mr=735.09,V=3223.2(18) 3,Z=4,Dc=1.515 Mg/m3,λ(MoKα)=0.71073 ,μ=1.022 mm-1,F(000)=1500,the final R=0.0464 and wR=0.1244.A total of 3218 unique reflections were collected,of which 2228 with I 〉 2σ(I) were observed.The Cu(II) atom is four-coordinated with two carboxylate oxygen atoms of the two pcpa ligands and two nitrogen atoms in thiazole rings of two aben ligands.The analysis of crystal structure shows intermolecular and intramolecular hydrogen bonds between amino-nitrogen atoms of the two aben ligands and carboxylate oxygen atoms of the two pcpa ligands.The antimicrobial properties of the title complex and its two free ligands were tested against representative bacterial and fungal strains.Results show that the antibacterial activity of the complex is less than or equal to that of 2-amino benzothiazole,but for yeasts and moulds,it exhibits excellent inhibitory effect better than that of its two free ligands. 展开更多
关键词 BENZOTHIAZOLE p-chlorophenoxyacetic acid ternary copper complex CRYSTALSTRUCTURE antimicrobial activity
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Development of Morus alba Reinforced Poly-Lactic Acid with Elevated Mechanical and Thermal Properties
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作者 Girish Kumar Reddy Madda Jens Schuster Yousuf Pasha Shaik 《Materials Sciences and Applications》 2024年第7期186-200,共15页
This research investigates the mechanical and thermal properties of Morus alba combined with polylactic acid in comparison with other natural fibers. The study uses three different fiber and PLA compositions - 20%, 30... This research investigates the mechanical and thermal properties of Morus alba combined with polylactic acid in comparison with other natural fibers. The study uses three different fiber and PLA compositions - 20%, 30%, and 40% respectively - to produce composite materials. In addition, another composite with the same fiber volume is treated with a 4% NaOH solution to improve mechanical properties. The composites are processed by twin-screw extrusion, granulation, and injection molding. Tensile strength measurements of raw fibers and NaOH-treated fibers were carried out using a single-fiber tensile test with a gauge length of 40 mm. It was observed that the NaOH surface treatment increases the resistance against tensile loading and exhibited improved properties for raw fiber strands. The diameter of the fibers was measured using optical microscopy. During this research, flexural tests, impact tests, differential scanning calorimetry (DSC), and heat deflection temperature measurements (HDT) were conducted to evaluate the mechanical and thermal properties of the developed composite samples. The results indicate that the mechanical properties of NaOH-treated Morus alba-reinforced polylactic acid outperform both virgin PLA samples and untreated Morus alba samples. 展开更多
关键词 Morus Alba Fiber (MAF) White Mulberry Polylactic acid (PLA) sodium Hydroxide (NaOH) Solution Single Fiber Tensile Test Thermal Stability Optical Microscopy
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Effect of sodium salicylate on oxidative stress and insulin resistance induced by free fatty acids 被引量:10
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作者 He, Bing Zhao, Sheng +2 位作者 Zhang, Wei Li, Yan Han, Ping 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2010年第1期49-53,共5页
BACKGROUND: It has been reported that high-dose salicylates improve free fatty acids (FFAs)-induced insulin resistance and beta-cell dysfunction in vitro, but the mechanism remains uncertain. In insulin-resistant rats... BACKGROUND: It has been reported that high-dose salicylates improve free fatty acids (FFAs)-induced insulin resistance and beta-cell dysfunction in vitro, but the mechanism remains uncertain. In insulin-resistant rats, we found that the supplementation of sodium salicylate is associated with a reduction of plasma malondialdehyde (MDA), a marker of oxidative stress. Few studies have investigated the effects of salicylates on oxidative stress levels in insulin-resistant animal models. This study aimed to assess the effect of sodium salicylate on insulin sensitivity and to explore the potential mechanism by which it improves hepatic and peripheral insulin resistance. METHODS: Intralipid+heparin (IH), saline (SAL), or intralipid+heparin+sodium salicylate (IHS) were separately infused for 7 hours in normal Wistar rats. During the last 2 hours of the infusion, hyperinsulinemic-euglycemic clamping was 3 performed with [6-(3)H] glucose tracer. Plasma glucose was measured using the glucose oxygenase method. Plasma insulin and C-peptide were determined by radioimmunoassay. MDA levels and glutathione peroxidase (GSH-PX) activity in the liver and skeletal muscle were measured with colorimetric kits. RESULTS: Compared with infusion of SAL, IH infusion increased hepatic glucose production (HGP), and decreased glucose utilization (GU) (P<0.05). The elevation of plasma free fatty acids increased the MDA levels and decreased the GSH-PX activity in the liver and muscle (P<0.01). Sodium salicylate treatment decreased HGP, elevated GU (P<0.05), reduced MDA content by 60% (P<0.01), and increased the GSH-PX activity by 35% (P<0.05). CONCLUSIONS: Short-term elevation of fatty acids induces insulin resistance by enhancing oxidative stress levels in the liver and muscle. The administration of the anti-inflammatory drug sodium salicylate reduces the degree of oxidative stress, therefore improving hepatic and peripheral insulin resistance. IKK-beta and NF-kappa B provide potential pathogenic links to oxidative stress. 展开更多
关键词 free fatty acids sodium salicylate oxidative stress insulin resistance hepatic glucose production
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Baeyer-Villiger oxidation of cyclic ketones utilizing potassium peroxydisulfate(K_2S_2O_8) or sodium perborate(NaBO_3) in acidic media 被引量:8
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作者 S.Zarrabi N.O.Mahmoodi +1 位作者 K.Tabatabaeian M.A.Zanjanchi 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第12期1400-1404,共5页
The efficient, green, facile, mild and straightforward conversion procedure for the oxidation of cyclic ketones to lactones at room temperature utilizing potassium peroxydisulfate (K2S2O8) in acidic media is satisfa... The efficient, green, facile, mild and straightforward conversion procedure for the oxidation of cyclic ketones to lactones at room temperature utilizing potassium peroxydisulfate (K2S2O8) in acidic media is satisfactory to high yields without using traditional chlorinated solvents is reported. This oxidative reagent is cheap and friendly environmental procedure for industrial purposes than use of organic peracids. 展开更多
关键词 Baeyer-Villiger oxidation Cyclic ketones Potassium peroxydisulfate (K2S208) acidic media sodium perborate (NaBO3)
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Redifferentiation of Human Gastric Cancer Cells Induced by Ascorbic Acid and Sodium Selenite 被引量:3
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作者 ZHENGQIU-SHENG SUNXI-LING 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2002年第3期223-232,共10页
Objective To explore the effects and mechanisms of ascorbic acid (AA) and sodium selenite (SS) on growth inhibition and redifferentiation in human gastric cancer cells. Methods In the present study, trypan blue dye... Objective To explore the effects and mechanisms of ascorbic acid (AA) and sodium selenite (SS) on growth inhibition and redifferentiation in human gastric cancer cells. Methods In the present study, trypan blue dye exclusion method was used to determine the cell growth curve and mitotic index, cell electrophoresis and colonogenic potential were used as the indexes of redifferentiation. In order to find out the mechanisms of redifferentiation, the activities of superoxide dismutase (SOD), glutathione peroxidase (GPX) and catalase (CAT) were assayed, the content of malondialdehyde (MDA), reduced glutathione (GSH) and H2O2 were evaluated. Results After treatment with AA 3 mol/L + SS 2μmol/L, the growth rate and mitotic index of human gastric cancer cells (MGc-803) decreased remarkably. The indexes related with cell malignancy were alleviated. For example, cell surface charge was obviously decreased, the electrophoresis rate was dropped from 2.21 to 1.15μm·s-1·V-1·cm-1. The indexes related with cell redifferentiation were promoted. For example, the colonogenic potential was decreased to 93.5%. These results indicated that redifferentiation of human gastric cancer cells was successfully induced by AA + SS. The activities of SOD and GPX were significantly higher, while the activity of CAT was slower in treated group than that in the control. The content of MDA was slightly decreased, GSH was sharply decreased, and H2O2 content was dramatically increased. Conclusion These results indicated that combination of ascorbic acid and sodium selenite may induce the redifferentiation of human gastric cancer cells and inhibit cell growth by virtue of enhancing the activities of antioxidative enzymes and inducing the formation of H2O2, and altering the cell redox status. Combination of ascorbic acid and sodium selenite may be a potent anticancer agent for human gastric cancer. 展开更多
关键词 Ascorbic acid sodium selenite Gastric cancer MALONDIALDEHYDE CATALASE Superoxide dismutase
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Role and Mechanism of Action of Exogenous Salicylic Acid and Sodium Molybdate in Improving Cold Tolerance of Bougainvillea glabra 被引量:5
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作者 Yongfu ZHANG Yanfen NIU Shengjing PENG 《Agricultural Biotechnology》 CAS 2018年第6期35-40,共6页
This study was conducted to comprehensively evaluate the effects of salicylic acid and sodium molybdate on cold tolerance of an ornamental plant Bougainvillea glabra and to provide a theoretical guidance for landscape... This study was conducted to comprehensively evaluate the effects of salicylic acid and sodium molybdate on cold tolerance of an ornamental plant Bougainvillea glabra and to provide a theoretical guidance for landscape maintenance.B.glabra plants were treated with 0.5 mmol/L salicylic acid and 2.0 μmol/L alone or in combination,and then exposed to low temperature stress before physiological indices were measured.The results showed that all salicylic acid and sodium molybdate treatments reduced the relative conductivity and malondialdehyde( MDA) content of B.glabra to varying extents under the stress of low temperature,and more significant effect was achieved by using the two agents in combination.Oxygen free radicals production rate increased with decreasing temperature from 20 to 6 ℃,but declined with temperature decreasing from 3 to-3 ℃.The SOD activity of the control( CK) was significantly lower than that of other treatments at 0 and-3 ℃.The treatments with salicylic acid and sodium molybdate alone and in combination increased POD activity of B.glabra plants,especially at 0 ℃,as the POD activity of treatments T1,T2 and T3 was significantly higher than that of CK at 0 ℃.In addition,under low temperature stress,the contents of soluble sugar,starch and proline increased initially and decreased subsequently with temperature decreasing.The soluble sugar content at 3 ℃,starch and proline contents at 0 and-3 ℃ in treatments with salicylic acid and sodium molybdate alone and in combination were significantly higher than those of CK.All above results proved that salicylic acid and sodium molybdate are able to improve cold tolerance of B.glabra,and better effect can be achieved by using them together. 展开更多
关键词 BOUGAINVILLEA glabra Salicylic acid sodium MOLYBDATE Low temperature stress Cold TOLERANCE PHYSIOLOGICAL mechanism
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Comparison of the impact of epigallocatechin gallate and ellagic acid in an experimental cataract model induced by sodium selenite 被引量:2
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作者 Irfan Ergen Burak Turgut Nevin Ilhan 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2017年第4期499-506,共8页
AIM:To compare the potential protective effects of epigallocatechin gallate(EGCG) and ellagic acid(EA) in an experimental cataract model.●METHODS:Twenty-eight Spraque-Dawley rat pups were assigned into four gro... AIM:To compare the potential protective effects of epigallocatechin gallate(EGCG) and ellagic acid(EA) in an experimental cataract model.●METHODS:Twenty-eight Spraque-Dawley rat pups were assigned into four groups.All the rats,except for those in the control group,were injected subcutaneously sodium selenite to induce experimental cataract on the postpartum ninth day,and between 10 th and 14 th days.Rats in the sham,EGCG,and EA groups were intraperitoneally administered 50 mg/(kg·d) saline solution,50 mg/(kg·d) EGCG and 200 mg/(kg·d) EA,respectively.The reduced glutathione(GSH) and malondialdehyde(MDA) levels,total antioxidant status(TAS) and total oxidant status(TOS) in lens supernatants were measured.RESULTS:The mean cataract gradings in EGCG and EA groups were found to be significantly lower than that in sham group(P〈0.001).The mean GSH levels and TASs in EGCG and EA groups were significantly higher than that in sham group while mean MDA levels and TOSs in EGCG and EA groups were significantly lower than that in the sham group(P〈0.001).CONCLUSION:EGCG and EA have protective effects on cataract development via the inhibition of oxidative stress. 展开更多
关键词 sodium selenite experimental cataract epigallocatechin gallate ellagic acid total oxidant status totalanti-oxidant status.
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A New One-dimensional Sodium Polymer Constructed from 4-Carboxy-benzenesulfonic Acid 被引量:2
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作者 王永伟 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第9期1312-1316,共5页
A new one-dimensional double chain coordination polymer, [Na(cbsH)(H2O)3]n (cbsH = 4-carboxy-benzenesulfonic anion), has been synthesized by aqueous reaction, structurally described, and thermally characterized.... A new one-dimensional double chain coordination polymer, [Na(cbsH)(H2O)3]n (cbsH = 4-carboxy-benzenesulfonic anion), has been synthesized by aqueous reaction, structurally described, and thermally characterized. It crystallizes in the triclinic system, space group P with a = 5.645(4), b = 7.905(5), c = 13.043(8) , α = 89.391(7), β = 80.637(7), γ = 82.845(7)°, V = 569.8(6) 3, Z = 2, C7H11NaO8S, Mr = 278.21, Dc = 1.622 Kg/m3, F(000) = 288, R = 0.0260 and wR = 0.0697. The title compound consists of one-dimensional double chains. 4-Carboxy-benzenesulfonic acid acts as a bridging bidentate ligand to link two sodium(I) ions to form a binuclear structure. Remarkably, the sodium(I) ion behaves as a metal bridge so that the binuclear structure units are connected to construct a one-dimensional double chain polymer. Furthermore, a 3-D framework is assembled through intermolecular hydrogen bonds. Thermogravimetric analysis shows that this compound begins losing the free solvent molecules at 106 ℃ and decompounding completely at 580 ℃. 展开更多
关键词 one-dimensional sodium polymer 4-carboxy-benzenesulfonic acid thermal property
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Determination of Iron in Layered Crystal Sodium Disilicate and Sodium Silicate by Flame Atomic Absorption Spectrometry with Boric Acid as a Matrix Modifier 被引量:1
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作者 Zhi Hua WANG Min CAI Shu Jun WANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第6期809-812,共4页
The effects of matrix silicate and experimental conditions on the determination of iron in flame atomic absorption spectrometry (FAAS) were investigated. It was found that boric acid as a matrix modifier obviously e... The effects of matrix silicate and experimental conditions on the determination of iron in flame atomic absorption spectrometry (FAAS) were investigated. It was found that boric acid as a matrix modifier obviously eliminated silicate interference. Under the optimum operating conditions, the determination results of iron in layered crystal sodium disilicate and sodium silicate samples by FAAS were satisfactory. The linear range of calibration curve is 0-10.5 μg.mL^-1, the relative standard deviation of method is 1.2%-2.2%, the recovery of added iron is 96.0%- 101%, the sensitivity is 0.19 μg.mL^-l and the detection limit is 77 ng.mL^-1. The effect of the determination of iron of the standard curve method, standard addition calibration and colorimetry method was the same, but the first has the merits of rapid sample preparation, reduced contamination risks and fast analysis. 展开更多
关键词 Layered crystal sodium disilicate sodium silicate flame atomic absorption spectrometry determination of iron boric acid.
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1-Heptanesulfonic acid sodium salt:One pot efficient synthesis of 2-aryl-1-arylmethyl-1H-1,3-benzo[d]imidazoles 被引量:1
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作者 Ganesh R.Jadhav Mohammad U.Shaikh +1 位作者 Rajesh P Kale Charansingh H.Gill 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第5期535-538,共4页
Synthesis of 2-aryl-1-arylmethyl-1H-1,3-benzo[d]imidazoles by the reaction of o-phenylenediamine with substituted aromatic aldehydes in the presence of 1-heptanesulfonic acid sodium salt (10 mol%) at room temperatur... Synthesis of 2-aryl-1-arylmethyl-1H-1,3-benzo[d]imidazoles by the reaction of o-phenylenediamine with substituted aromatic aldehydes in the presence of 1-heptanesulfonic acid sodium salt (10 mol%) at room temperature. The reactions were performed in acetonitrile:water (8:2). The method was proved to be eco-friendly, convenient and the products were isolated with good yields (82- 90%). 展开更多
关键词 1-Heptanesulfonic acid sodium salt Water Aryl aldehyde BENZIMIDAZOLE
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Effects of adding sodium dichloroacetate to low-protein diets on nitrogen balance and amino acid metabolism in the portaldrained viscera and liver of pigs 被引量:2
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作者 Weizhong Sun Yunxia Li +5 位作者 Zhiru Tang Huiyuan Chen Ke Wan Rui An Liuting Wu Zhihong Sun 《Journal of Animal Science and Biotechnology》 CAS CSCD 2020年第3期884-895,共12页
Background:Identifying regulatory measures to promote glucose oxidative metabolism while simultaneously reducing amino acid oxidative metabolism is one of the foremost challenges in formulating low-protein(LP)diets de... Background:Identifying regulatory measures to promote glucose oxidative metabolism while simultaneously reducing amino acid oxidative metabolism is one of the foremost challenges in formulating low-protein(LP)diets designed to reduce the excretion of nitrogen-containing substances known to be potential pollutants.In this study,we investigated the effects of adding sodium dichloroacetate(DCA)to a LP diet on nitrogen balance and amino acid metabolism in the portal-drained viscera(PDV)and liver of pigs.To measure nitrogen balance,18 barrows(40±1.0 kg)were fed one of three diets(n=6 per group):18%crude protein(CP,control),13.5%CP(LP),and 13.5%CP+100 mg DCA/kg dry matter(LP-DCA).To measure amino acid metabolism in the PDV and liver,15 barrows(40±1.0 kg)were randomly assigned to one of the three diets(n=5 per group).Four essential amino acids(Lys,Met,Thr,and Trp)were added to the LP diets such that these had amino acid levels comparable to those of the control diet.Results:The LP-DCA diet reduced nitrogen excretion in pigs relative to that of pigs fed the control diet(P<0.05),without any negative effects on nitrogen retention(P>0.05).There were no differences between the control and LP-DCA groups with respect to amino acid supply to the liver and extra-hepatic tissues in pigs(P>0.05).The net release of ammonia into the portal vein and production rate of urea in the liver of pigs fed the LP-DCA diet was reduced relative to that of pigs fed the control and LP diets(P<0.05).Conclusion:The results indicated that addition of DCA to a LP diet can efficiently reduce nitrogen excretion in pigs and maximize the supply of amino acids to the liver and extra-hepatic tissues. 展开更多
关键词 Amino acid metabolism Low-protein diet Nitrogen excretion PIG sodium dichloroacetate
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The Antidotal Effects of High-dosage γ-Aminobutyric Acid on Acute Tetramine Poisoning as Compared with Sodium Dimercaptopropane Sulfonate 被引量:1
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作者 孙鹏 韩继媛 温宇英 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2007年第4期419-421,共3页
To investigate the therapeutic effect of nigh-dosage γ-aminobutyric acid (GABA) on acute tetramine (TET) poisoning, 50 Kunming mice were divided into 5 groups at random and the antidotal effects of GABA or sodium... To investigate the therapeutic effect of nigh-dosage γ-aminobutyric acid (GABA) on acute tetramine (TET) poisoning, 50 Kunming mice were divided into 5 groups at random and the antidotal effects of GABA or sodium dimercaptopropane sulfonate (Na-DMPS) on poisoned mice in different groups were observed in order to compare the therapeutic effects of nigh-dosage GABA with those of Na-DMPS. Slices of brain tissue of the poisoned mice were made to examine pathological changes of cells. The survival analysis was employed. Our results showed that both high-dosage GABA and Na-DMPS could obviously prolong the survival time, delay onset of convulsion and muscular twitch, and ameliorate the symptoms after acute tetramine poisoning in the mice. Better effects could be achieved with earlier use of high dosage GABA or Na-DMPS. There was no significant difference in prolonging the survival time between high-dose GABA and Na-DMPS used immediately after poisioning. It is concluded that high-dosage GABA can effectively antagonize acute toxicity of terarnine in mice. And it is suggested that nigh-dosage GABA may be used as an excellent antidote for acute TET poisoning in clinical practice. The indications and correct dosage for clinical use awaits to be further studied. 展开更多
关键词 TETRAMINE γ-aminobutyfic acid sodium dimercaptopropane sulfonate experimental therapy
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Oxalic Acid Promoted Hydrolysis of Sodium Borohydride for Transition Metal Free Hydrogen Generation 被引量:1
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作者 PENG Yuanting ZENG Hui +5 位作者 SHI Yu XU Jinrong 谢镭 陈均 ZHENG Jie LI Xingguo 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2020年第6期1011-1015,共5页
We reported an inexpensive and high-efficiency hydrogen generation method from NaBH4 hydrolysis promoted by oxalic acid.NaBH4 and H2C2O4 were premixed and hydrogen generation was initiated by adding water into the sol... We reported an inexpensive and high-efficiency hydrogen generation method from NaBH4 hydrolysis promoted by oxalic acid.NaBH4 and H2C2O4 were premixed and hydrogen generation was initiated by adding water into the solid mixture.H2C2O4 was selected as the acid promotor due to its solid state and low mass per proton.The effect of reactant ratio on the hydrogen yield and hydrogen storage density was investigated.With optimized reactant ratio,high gravimetric hydrogen storage up to 4.4wt%based on all the reactants can be achieved with excellent hydrogen generation kinetics. 展开更多
关键词 hydrogen generation sodium borohydride oxalic acid HYDROLYSIS
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SYNERGISM OF WOLFRAMITE FLOTATION WITH BENZYL ARSONIC ACID AND SODIUM BUTYL XANTHATE 被引量:1
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作者 Liu Deqian Zhou Chunshan Wang Dianzuo 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 1992年第3期37-42,共6页
Wolframite notation with benzyl arsonic acid and sodium butyl xanthate is studied,at first.It shows the efficiency of mineral processig is good when the two agents are added together.Then the synergism of sodium butyl... Wolframite notation with benzyl arsonic acid and sodium butyl xanthate is studied,at first.It shows the efficiency of mineral processig is good when the two agents are added together.Then the synergism of sodium butyl xanthate and benzyl arsonic acid is studied also by HPLC. 展开更多
关键词 HPLC synergism WOLFRAMITE benzyl arsonic acid sodium butyl xanthate
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Development of Better-Quality Assay Method for the Citric Acid and Sodium Citrate in Ophthalmic/Oral Solutions and Their Application to Deformulation Studies 被引量:1
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作者 Kishore Kumar Hotha Tejashkumar Patel +1 位作者 Swapan Roychowdhury Veerappan Subramanian 《American Journal of Analytical Chemistry》 2014年第17期1249-1260,共12页
There were several techniques determined for the analysis of citrate and citric acid mixtures in the pharmaceutical dosage forms. Titration methods, photometric and ion chromatographic methods were used for their dete... There were several techniques determined for the analysis of citrate and citric acid mixtures in the pharmaceutical dosage forms. Titration methods, photometric and ion chromatographic methods were used for their determination. These methods will restrict too many factors where the accurate quantification of citrate and citric acid is extremely challenging. Citric acid is the natural flavor used as a preservative for many pharmaceutical applications. Deformulation techniques used for the manufacturing of generic drugs require authentic data for their regulatory submissions. Simple accurate and reproducible validated method developed for the determination of citric acid and sodium citrate by titration followed by HPLC analysis. Free citric acid was determined by the titration method and total citric acid was determined by HPLC analysis. After subtracting the free citric acid from total citric acid content, citric acid present in the sodium citrate content was determined. Sodium citrate content was determined by applying sodium correction factor to the subtracted value of the citric acid. The results met all the validation parameters and the method was successfully measured the amount of citric acid and sodium citrate in the marketed ophthalmic/oral solutions. 展开更多
关键词 Citric acid sodium CITRATE OPHTHALMIC SOLUTIONS ORAL SOLUTIONS TITRATION HPLC
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OBSERVATION OF THE EFFECT OF S-(-)USNIC ACID SODIUM ON TRICHOMONAS VAGINALIS BY TRANSMISSION ELECTRON MICROSCOPE 被引量:1
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作者 吴杰 张敏如 +2 位作者 丁东宁 谭廷华 闫宝琦 《Journal of Pharmaceutical Analysis》 CAS 1994年第1期56-59,共4页
This paper reports the ultrastructural changes of trichomonas vaginaiis (T. vag. ) under the action of s-(-)usnic acid sodium in vitro. These changes can be shown by the following results:At first, the degranulation o... This paper reports the ultrastructural changes of trichomonas vaginaiis (T. vag. ) under the action of s-(-)usnic acid sodium in vitro. These changes can be shown by the following results:At first, the degranulation of the rough endoplasmic reticulum (RER) took place, the polyribosomes disaggregated. And then, the Golgi complex and the endoplasmic reticulum dilated. The cytoplasmic matrix presented and inhomogeneous apperance. Finally, the biomembrane loosed and fractured.The cell nuclei presented the karyorrhexis. 展开更多
关键词 s-(-)usnic acid sodium trichomonas vaginalis (T. vag. ) ULTRASTRUCTURE transmission electron microscope (TEM)
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Pediatric bowel preparation: Sodium picosulfate, magnesium oxide, citric acid vs polyethylene glycol, a randomized trial 被引量:1
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作者 Carmen Cuffari Steven L Ciciora +2 位作者 Masakazu Ando Mena Boules Joseph M Croffie 《World Journal of Gastroenterology》 SCIE CAS 2020年第40期6260-6269,共10页
BACKGROUND Bowel preparation in children can be challenging.AIM To describe the efficacy, safety, and tolerability of sodium picosulfate, magnesium oxide, and citric acid(SPMC) bowel preparation in children.METHODS Ph... BACKGROUND Bowel preparation in children can be challenging.AIM To describe the efficacy, safety, and tolerability of sodium picosulfate, magnesium oxide, and citric acid(SPMC) bowel preparation in children.METHODS Phase 3, randomized, assessor-blinded, multicenter study of low-volume, divided dose SPMC enrolled children 9-16 years undergoing elective colonoscopy. Participants 9-12 years were randomized 1:1:1 to SPMC ? dose × 2, SPMC 1 dose × 2, or polyethylene glycol(PEG). Participants 13-16 years were randomized 1:1 to SPMC 1 dose × 2 or PEG. PEG-based bowel preparations were administered per local protocol. Primary efficacy endpoint for quality of bowel preparation was responders(rating of ‘excellent' or ‘good') by modified Aronchick Scale. Secondary efficacy endpoint was participant's tolerability and satisfaction from a 7-item questionnaire. Safety assessments included adverse events(AEs) and laboratory evaluations.RESULTS 78 participants were randomized, 48 were 9-12 years, 30 were 13-16 years. For the primary efficacy endpoint in 9-12 years, 50.0%, 87.5%, and 81.3% were responders for SPMC ? dose × 2, SPMC 1 dose × 2, and PEG groups, respectively. Responder rates for 13-16 years were 81.3% for SPMC 1 dose × 2 and 85.7% for PEG. Overall, 43.8% of participants receiving SPMC 1 dose × 2 reported it was ‘very easy' or ‘easy' to drink, compared with 20.0% receiving PEG. Treatment-emergent AEs were reported by 45.5% of participants receiving SPMC 1 dose × 2 and 63.0% receiving PEG.CONCLUSION SPMC was an efficacious and safe for bowel preparation in children 9-16 years, with comparable efficacy to PEG. Tolerability for SPMC was higher compared to PEG. 展开更多
关键词 CHILDREN COLONOSCOPY Colon cleansing sodium picosulfate magnesium oxide and citric acid Polyethylene glycol
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Determination of pKa values of alendronate sodium in aqueous solution by piecewise linear regression based on acid-base potentiometric titration 被引量:2
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作者 Jing Ke Hanfei Dou +3 位作者 Ximin Zhang Dushimabararezi Serge Uhagaze Xiali Ding Yuming Dong 《Journal of Pharmaceutical Analysis》 SCIE CAS 2016年第6期404-409,共6页
As a mono-sodium salt form of alendronic acid,alendronate sodium presents multi-level ionization for the dissociation of its four hydroxyl groups.The dissociation constants of alendronate sodium were determined in thi... As a mono-sodium salt form of alendronic acid,alendronate sodium presents multi-level ionization for the dissociation of its four hydroxyl groups.The dissociation constants of alendronate sodium were determined in this work by studying the piecewise linear relationship between volume of titrant and p H value based on acidbase potentiometric titration reaction.The distribution curves of alendronate sodium were drawn according to the determined p Ka values.There were 4 dissociation constants(pKa_1=2.43,pKa_2=7.55,pKa_3=10.80,pKa_4=11.99,respectively) of alendronate sodium,and 12 existing forms,of which 4 could be ignored,existing in different p H environments. 展开更多
关键词 Dissociation CONSTANTS ALENDRONATE sodium Distribution curve Piecewise linear regression acid-BASE POTENTIOMETRIC TITRATION
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Isotopic Shifts of the infrared Spectra of Cholic Acid and Sodium Cholate
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《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1994年第1期59-62,共4页
IsotopicShiftsoftheinfraredSpectraofCholicAcidandSodiumCholateTIANWen;WENGShi-fu;WUJin-guangandZHANGQing-lia... IsotopicShiftsoftheinfraredSpectraofCholicAcidandSodiumCholateTIANWen;WENGShi-fu;WUJin-guangandZHANGQing-lian(T.L-CHANG)(Depa... 展开更多
关键词 Cholic acid sodium cholate DEUTERATION Infrared spectra Isotopic shift
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Relationships of CDXs and apical sodium-dependent bile acid transporter in Barrett's esophagus 被引量:3
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作者 Jingbo Zhao Hans Gregersen 《World Journal of Gastroenterology》 SCIE CAS 2013年第18期2736-2739,共4页
Barrett's esophagus (BE) is characterized by intestinal metaplasia with the differentiated epithelium replaced by another type of epithelium morphologically similar to normal intestinal epithelium. The metaplasia ... Barrett's esophagus (BE) is characterized by intestinal metaplasia with the differentiated epithelium replaced by another type of epithelium morphologically similar to normal intestinal epithelium. The metaplasia is preceded by bile and acid reflux into the esophagus. BE is a premalignant condition associated with increased risk of esophageal cancer, especially esophageal adenocarcinoma. The Caudal-related homeodomain transcription factors Caudal-related homeodomain transcription factor CDX1 and CDX2 are expressed exclusively in the small and large intestine, playing important roles in proliferation and differentiation of intestinal epithelial cells. Ectopic expression of CDX1 and CDX2 occurs in BE. The apical sodium-dependent bile acid transporter (ASBT) is expressed primarily in terminal ileum where it is a key factor for intestinal reabsorption of bile salts. In addition to upregulation of CDX1 and CDX2, ASBT expression is up-regulated in BE. Furthermore, both CDX1/CDX2 and ASBT expressions are down-regulated in high-grade esophageal dysplasia. The alteration of the above-mentioned factors calls for attention: what is the relationship between CDXs and ASBT aberrant expression in BE? In this commentary, we discuss this issue on basis of the recent study done by Ma et al . 展开更多
关键词 ESOPHAGUS Intestinal METAPLASIA Caudal-related HOMEODOMAIN transcription factors APICAL sodiumdependent bile acid TRANSPORTER Aberrant expression
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