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Partially hydrolyzed guar gum in pediatric functional abdominal pain 被引量:5
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作者 Claudio Romano Donatella Comito +2 位作者 Annalisa Famiani Sabrina Calamarà Italia Loddo 《World Journal of Gastroenterology》 SCIE CAS 2013年第2期235-240,共6页
AIM:To assess the effects of partially hydrolyzed guar gum(PHGG) diet supplement in pediatric chronic abdominal pain(CAP) and irritable bowel syndrome(IBS).METHODS:A randomized,double-blind pilot study was performed i... AIM:To assess the effects of partially hydrolyzed guar gum(PHGG) diet supplement in pediatric chronic abdominal pain(CAP) and irritable bowel syndrome(IBS).METHODS:A randomized,double-blind pilot study was performed in sixty children(8-16 years) with functional bowel disorders,such as CAP or IBS,diagnosed according to Rome Ⅲ criteria.All patients underwent ultrasound,blood and stool examinations to rule out any organic disease.Patients were allocated to receive PHGG at dosage of 5 g/d(n = 30) or placebo(fruitjuice n = 30) for 4 wk.The evaluation of the efficacy of fiber supplement included IBS symptom severity score(Birmingham IBS Questionnaire),severity of abdominal pain(Wong-Baker Face Pain Rating Score) and bowel habit(Bristol Stool Scale).Symptom scores were completed at 2,4,and 8 wk.The change from baseline in the symptom severity scale at the end of treatment and at 4 wk follow-up after treatment was the primary endpoint.The secondary endpoint was to evaluate compliance to supplementation with the PHGG in the pediatric population.Differences within groups during the treatment period and follow-up were evaluated by the Wilcoxon signed-rank test.RESULTS:The results of the study were assessed considering some variables,such as frequency and intensity of symptoms with modifications of the bowel habit.Both groups were balanced for baseline characteristics and all patients completed the study.Group A(PHGG group) presented a higher level of efficacy compared to group B(control group),(43% vs 5%,P = 0.025) in reducing clinical symptoms with modification of Birmingham IBS score(median 0 ± 1 vs 4 ± 1,P = 0.025),in intensity of CAP assessed with the Wong-Baker Face Pain Rating Score and in normalization of bowel habit evaluated with the Bristol Stool Scale(40% vs 13.3%,P = 0.025).In IBS subgroups,statistical analysis shown a tendency toward normalization of bowel movements,but there was no difference in the prevalence of improvement in two bowel habit subsets.PHGG was therefore better tolerated without any adverse effects.CONCLUSION:Although the cause of pediatric functional gastrointestinal disorders is not known,the results show that complementary therapy with PHGG may have beneficial effects on symptom control. 展开更多
关键词 Functional BOWEL DISORDERS PARTIALLY hydrolyzed GUAR gum PEDIATRIC chronic ABDOMINAL pain Fiber diet
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Effect of Dietary Supplementation with Hydrolyzed Wheat Gluten on Growth Performance, Cell Immunity and Serum Biochemical Indices of Weaned Piglets (Sus scrofa) 被引量:7
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作者 WANG Xiu-qi FENG You +3 位作者 SHU Gang JIANG Qing-yan YANG Jing-pei ZHANG Zi-feng 《Agricultural Sciences in China》 CAS CSCD 2011年第6期938-945,共8页
To investigate the effects of dietary supplementation with hydrolyzed wheat gluten (HWG) on growth performance, cell immunity and serum biochemical indices of weaned piglets, 160 crossed (Large White×andrace)... To investigate the effects of dietary supplementation with hydrolyzed wheat gluten (HWG) on growth performance, cell immunity and serum biochemical indices of weaned piglets, 160 crossed (Large White×andrace) and weaned piglets were randomly divided into 4 treatments with 4 replicates of 10 piglets each. The piglets in each treatment were fed an experimental diet containing either 0 g kg-1 HWG (control group), 30 g kg-1 HWG (3% HWG group), 50 g kg-1 HWG (5% HWG group), or 2.5 g kg-1 glycyl-L-glutamine (0.25% Gly-Gln group). The results showed that the diarrhea rates in 3% HWG and 5% HWG groups were significantly lower than in control group from d 1 to 14 (P〈0.05), while the average daily gain (ADG) in each of two groups was increased (P〉0.05). When compared with control group, dietary supplementation with 3% HWG increased the ratio of CD4+:CD8+ and the ratio of serum albumin and globulin concentrations (A:G) on d 14 and 28, as well as the proliferation of T- and B-lymphocytes (P〉0.05) on d 28. In addition, on d 14 and 28, the A:G ratio in 5% HWG group was significantly higher than in control group (P〈0.05), while the ratio of CD4+:CD8+ increased slightly (P〉0.05). Interestingly, 0.25% Gly-Gln group had higher proportion of CD3+ (P〉0.05) and CD4+ (P〈0.05) on d 14 than control group, but growth performances of 0.25% Gly-Gln group were negatively affected at all experiment stages. These results suggested that HWG might improve the growth performance of piglets by strengthening cell immunity and decreasing the occurrence of diarrhea during the prophase after weaning. 展开更多
关键词 hydrolyzed wheat gluten weaned piglets growth performance cell immunity serum biochemical indices
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Effect of salt solutions on chain structure of partially hydrolyzed polyacrylamide 被引量:2
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作者 张青 周吉生 +2 位作者 翟永爱 刘凤岐 高歌 《Journal of Central South University》 SCIE EI CAS 2008年第S1期80-83,共4页
The effect of salt solutions(NaCl,Na2SO4 and CaCl2) on the conformational properties of partially hydrolyzed polyacrylamide(HPAM) was investigated by using static laser light scattering(SLLS).The special interaction b... The effect of salt solutions(NaCl,Na2SO4 and CaCl2) on the conformational properties of partially hydrolyzed polyacrylamide(HPAM) was investigated by using static laser light scattering(SLLS).The special interaction between CaCl2 solution and HPAM was also researched.Experimental results show that the chain structure of HPAM is interrelated with the charge density,the kind and the concentration of salt solutions.The mean-square radius of gyration(Rz) and the second virial coefficient(A2) of HPAM decrease with increasing concentration of salt solutions,and the salt effect tends towards the maximum when the concentration of salt solution is increased to some amount. 展开更多
关键词 PARTIALLY hydrolyzed polyacrylamide(HPAM) SALT EFFECT chain structure static laser light scattering(SLLS)
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Separation of diaspore from bauxite by selective flocculation using hydrolyzed polyacrylamide 被引量:6
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作者 刘文莉 胡岳华 孙伟 《Journal of Central South University》 SCIE EI CAS 2014年第4期1470-1476,共7页
Selective flocculation is a new method to solve the problem of China's bauxite de-silication besides flotation and reverse flotation. The method of selective flocculation of bauxite using hydrolyzed polyacrylamide... Selective flocculation is a new method to solve the problem of China's bauxite de-silication besides flotation and reverse flotation. The method of selective flocculation of bauxite using hydrolyzed polyacrylamide as flocculant was experimented and evaluated. The results of diaspore and kaolinite single mineral settling tests show that the difference between settlement yield of kaolinite(settling 15 min) and diaspore(settling 3 min) increases from 16% to 60% by adding flocculant at pH=7. Results of selective flocculation experiment of bauxite show that the higher concentrate grade(65.75) and Al-Si ratio(7.34) could be obtained with sodium carbonate as dispersant compared with sodium hexametaphosphate; under the action of flocculating agent, the concentrate grade and Al-Si ratio increase to 67.99 and 9.01. These results could meet the requirements of Bayer production, and the simpler process was expected to cost far less than traditional flotation method and a promising de-silication method of bauxite. 展开更多
关键词 hydrolyzed polyacrylamide selective flocculation diaspore anion maromolecular
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Partially hydrolyzed guar gum attenuates non-alcoholic fatty liver disease in mice through the gut-liver axis 被引量:5
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作者 Shun Takayama Kazuhiro Katada +14 位作者 Tomohisa Takagi Takaya Iida Tomohiro Ueda Katsura Mizushima Yasuki Higashimura Mayuko Morita Tetsuya Okayama Kazuhiro Kamada Kazuhiko Uchiyama Osamu Handa Takeshi Ishikawa Zenta Yasukawa Tsutomu Okubo Yoshito Itoh Yuji Naito 《World Journal of Gastroenterology》 SCIE CAS 2021年第18期2160-2176,共17页
BACKGROUND The gut-liver axis has attracted much interest in the context of chronic liver disease pathogenesis.Prebiotics such as dietary fibers were shown to attenuate non-alcoholic fatty liver disease(NAFLD)by modul... BACKGROUND The gut-liver axis has attracted much interest in the context of chronic liver disease pathogenesis.Prebiotics such as dietary fibers were shown to attenuate non-alcoholic fatty liver disease(NAFLD)by modulating gut microbiota.Partially hydrolyzed guar gum(PHGG),a water-soluble dietary fiber,has been reported to alleviate the symptoms of various intestinal diseases and metabolic syndromes.However,its effects on NAFLD remain to be fully elucidated.To determine whether treatment with PHGG attenuates NAFLD development in mice through the gut-liver axis.METHODS Seven-week-old male C57BL/6J mice with increased intestinal permeability were fed a control or atherogenic(Ath)diet(a mouse model of NAFLD)for 8 wk,with or without 5%PHGG.Increased intestinal permeability was induced through chronic intermittent administration of low-dose dextran sulfate sodium.Body weight,liver weight,macroscopic findings in the liver,blood biochemistry[aspartate aminotransferase(AST)and alanine aminotransferase(ALT),total cholesterol,triglyceride,free fatty acids,and glucose levels],liver histology,myeloperoxidase activity in liver tissue,mRNA expression in the liver and intestine,serum endotoxin levels in the portal vein,intestinal permeability,and microbiota and short-chain fatty acid(SCFA)profiles in the cecal samples were investigated.RESULTS Mice with increased intestinal permeability subjected to the Ath diet showed significantly increased serum AST and ALT levels,liver fat accumulation,liver inflammatory(tumor necrosis factor-αand monocyte chemotactic protein-1)and fibrogenic(collagen 1a1 andαsmooth muscle actin)marker levels,and liver myeloperoxidase activity,which were significantly attenuated by PHGG treatment.Furthermore,the Ath diet combined with increased intestinal permeability resulted in elevated portal endotoxin levels and activated toll-like receptor(TLR)4 and TLR9 expression,confirming that intestinal permeability was significantly elevated,as observed by evaluating the lumen-to-blood clearance of fluorescein isothiocyanate-conjugated dextran.PHGG treatment did not affect fatty acid metabolism in the liver.However,it decreased lipopolysaccharide signaling through the gut-liver axis.In addition,it significantly increased the abundance of cecal Bacteroides and Clostridium subcluster XIVa.Treatment with PHGG markedly increased the levels of SCFAs,particularly,butyric acid,acetic acid,propionic acid,and formic acid,in the cecal samples.CONCLUSION PHGG partially prevented NAFLD development in mice through the gut-liver axis by modulating microbiota and downstream SCFA profiles. 展开更多
关键词 Non-alcoholic fatty liver disease Partially hydrolyzed guar gum Gut-liver axis Intestinal barrier integrity MICROBIOTA Short-chain fatty acids
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Oxidation of Partially Hydrolyzed Polyacrylamide from Polymer Flooding Processes Using Fenton Reagents 被引量:1
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作者 Li Jinlian Wang Jia +2 位作者 Liu Hongyan Wu HongJun Zhang Yongjun 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2023年第4期86-92,共7页
The degradation of partially hydrolyzed polyacrylamide(HPAM) found in alkaline/surfactant/polymer flooding sewage was investigated using Fenton-type reagents. Different Fenton reagent treatments for HPAM degradation w... The degradation of partially hydrolyzed polyacrylamide(HPAM) found in alkaline/surfactant/polymer flooding sewage was investigated using Fenton-type reagents. Different Fenton reagent treatments for HPAM degradation were compared. The effects of pH, hydrogen peroxide(H_(2)O_(2)), ferrous ion(Fe^(2+)), and tartaric ion(C_(4)H_(4)O_(6)^(2-)) concentrations were studied. The degradation reaction occurred within a wide range of pH(3–9). The HPAM degradation performance of photo-Fenton processes using solar light and UV were compared with that of the Fenton process. The degradation rate was found to be strongly dependent on the H_(2)O_(2)/Fe^(2+)/C_(4)H_(4)O_(6)^(2-)molar ratio. The HPAM degradation efficiency was 90%, and the chemical oxygen demand removal efficiency was 85%. HPAM could be degraded into a compound with a lower molecular weight, but it was difficult to achieve complete mineralization to CO_(2). The presence of intermediate products hindered further oxidation in the Fenton process. 展开更多
关键词 PHOTODEGRADATION UV Fenton reagent partially hydrolyzed polyacrylamide
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INTERACTION OF COMPONENTS IN PETROLEUM CARBOXYLATE/ALKALINE/HYDROLYZED POLYACRYLAMIDE FLOODING SYSTEM 被引量:1
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作者 HONG DU HUANG LIN ZHAO Jianghan Petroleum Institute,Jiangling,Hubei,434102 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第3期279-280,共2页
The IFTs(Interfacial tension)of petroleum carboxylate/alkaline/HPAM(Hydrolyzed polyacrylamide)flooding system with Daing crude oil and the effects of petroleum carboxylate and alkaline on viscoaity of HPAM solution we... The IFTs(Interfacial tension)of petroleum carboxylate/alkaline/HPAM(Hydrolyzed polyacrylamide)flooding system with Daing crude oil and the effects of petroleum carboxylate and alkaline on viscoaity of HPAM solution were studied.There exists remarkable synergism between HPAM and petroleum carboxylate,and the introduction of HPAM into petroleum carboxylate/alka- line system leads the lowering of IFTs against Daqing crude oil,The introduction of petroleum carboxylate into solution of HPAM also leads the decreasing of viscosity,but the extent of viscosity decreasing is much lower than that caused by inorganic salts such as NaCl and CaCl_2. 展开更多
关键词 HPAM this INTERACTION OF COMPONENTS IN PETROLEUM CARBOXYLATE/ALKALINE/hydrolyzeD POLYACRYLAMIDE FLOODING SYSTEM IFT than EOR
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Hypoallergenicity of a thickened hydrolyzed formula in children with cow’s milk allergy
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作者 Danilo Rossetti Salvatore Cucchiara +2 位作者 AlessANDra Morace Beatrice Leter Salvatore Oliva 《World Journal of Clinical Cases》 SCIE 2019年第16期2256-2268,共13页
BACKGROUND Allergy to cow’s milk is the most frequent allergy occurring in infants and young children.The dietary management of these patients consists of the elimination of any cow’s milk proteins from the diet,and... BACKGROUND Allergy to cow’s milk is the most frequent allergy occurring in infants and young children.The dietary management of these patients consists of the elimination of any cow’s milk proteins from the diet,and for formula-fed infants,the substitution of the usual infant formula with an adapted formula that is generally based on extensively hydrolyzed cow’s milk proteins.The American Academy of Pediatrics has established specific criteria to confirm the hypoallergenicity of a formula intended for these children.AIM To assess the hypoallergenicity of a new thickened extensively hydrolyzed casein-based formula (TeHCF) in children with cow’s milk allergy (CMA).METHODS Children diagnosed with CMA through a double-blind placebo-controlled food challenge (DBPCFC) were randomly administered increased doses of a placebo formula or the TeHCF [Allernova,new thickener including fibres (Novalac)] under double-blind conditions and medical surveillance on two separate days.Otherwise,both of these formulas and a cow’s milk-based formula were randomly introduced to children who were highly suspected of having CMA on three separate days.Immediate and late reactions occurring after the introduction of any of these formulas were thoroughly recorded by the physician at the hospital and reported by parents to the physician after hospital discharge,respectively.If the children tolerated the TeHCF during the DBPCFC,they were exclusively fed this formula during a 3-mo period where potential allergic symptoms,anthropometric parameters,as secondary outcomes,and adverse events were registered.The Cow’s Milk-related Symptoms Score (CoMiSSTM) was assessed and anthropometric parameters were compared to World Health Organization (WHO) reference data.RESULTS Of the 30 children included in the study,the CMA diagnosis of 29 (mean age: 8.03 ± 7.43 mo) patients was confirmed by a DBPCFC.The children all tolerated the TeHCF during both the challenge and the subsequent 3-mo feeding period,which they all completed.During the latter period,the CoMiSSTM remained at a very low level,never exceeding its baseline value (1.4 ± 2.0),growth parameters were within WHO reference standards and no adverse event related to the TeHCF was reported.Over the first week of this period,the proportion of patients with digestive discomfort significantly decreased from 20.7%(6/29) to 3.4%(1/29),P = 0.025.The proportion of satisfaction with the overall effect of the formula reported by the parents and investigator was high,as was the formula acceptability by the child.CONCLUSION The new TeHCF meets the hypoallergenicity criteria according to the American Academy of Pediatrics standards,confirming that the tested TeHCF is adapted to the dietary management of children with CMA.Moreover,growth was adequate in the included population. 展开更多
关键词 Cow's milk ALLERGY Hypoallergenicity Tolerance Thickened extensively hydrolyzed FORMULA DIGESTIVE COMFORT DIETARY management
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Enhanced Redispersibility of Cellulose Nanocrystals in Water via Surface Adsorption of Hydrolyzed Sugars from Corresponding Cellulose Nanocrystal Fabrication
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作者 Yongqi Zhang Yongjian Xu +4 位作者 Chun Liu Ling Yang Jianmin Hu Ruixia Zhang Xiuqiong Guan 《Paper And Biomaterials》 CAS 2022年第2期10-17,共8页
Generally,hydrogen bonds are formed between cellulose nanocrystals(CNCs)during their water removal and drying,leading to the irreversible aggregation of CNCs,and thus a poor water-redispersibility.The present study de... Generally,hydrogen bonds are formed between cellulose nanocrystals(CNCs)during their water removal and drying,leading to the irreversible aggregation of CNCs,and thus a poor water-redispersibility.The present study demonstrated a novel approach that involved using hydrolyzed sugars generated from the corresponding CNC production as redispersing agents to enhance the redispersibility of CNCs.Experimental data indicated that hydrolyzed sugars can be adsorbed onto CNCs through ethanol precipitation.The oven-dried CNCs onto which hydrolyzed sugars were adsorbed via ethanol precipitation were homogeneously redispersed in water.The redispersed CNCs showed the particle size distribution,Zeta potential,and thermal decomposition properties similar to those of the CNCs without drying.This method may improve the use of hydrolyzed sugars obtained in the hydrolysate from the corresponding CNC production,as well as facilitate the transportation and storage of CNCs. 展开更多
关键词 water redispersion cellulose nanocrystals(CNCs) hydrolyzed sugars ethanol precipitation
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Effects of synthesis conditions on layered Li[Ni_(1/3)Co_(1/3)Mn_(1/3)]O_2 positive-electrode via hydroxide co-precipitation method for lithium-ion batteries 被引量:7
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作者 胡传跃 郭军 +2 位作者 杜勇 徐洪辉 贺跃辉 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第1期114-120,共7页
Layered Li[Ni1/3Co1/3Mn1/3]O2 was synthesized with complex metal hydroxide precursors that were prepared by a co-precipitation method.The influence of coordination between ammonia and transition-metal cations on the s... Layered Li[Ni1/3Co1/3Mn1/3]O2 was synthesized with complex metal hydroxide precursors that were prepared by a co-precipitation method.The influence of coordination between ammonia and transition-metal cations on the structural and electrochemical properties of the Li[Ni1/3Co1/3Mn1/3]O2 materials was studied.It is found that when the molar ratio of ammonia to total transition-metal cations is 2.7:1,uniform particle size distribution of the complex metal hydroxide is observed via scanning electron microscopy.The average particle size of Li[Ni1/3Co1/3Mn1/3]O2 materials was measured to be about 500 nm,and the tap-density was measured to be approximately 2.37 g/cm3,which is comparable with that of commercialized LiCoO2.XRD analysis indicates that the presently synthesized Li[Ni1/3Co1/3Mn1/3]O2 has a hexagonal layered-structure.The initial discharge capacity of the Li[Ni1/3Co1/3Mn1/3]O2 positive-electrode material is determined to be 181.5 mA·h/g using a Li/Li[Ni1/3Co1/3Mn1/3]O2 cell operated at 0.1C in the voltage range of 2.8-4.5 V.The discharge capacity at the 50th cycle at 0.5C is 170.6 mA·h/g. 展开更多
关键词 layered structure coordination effect hydroxide co-precipitation cathode material lithium ion batteries
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Recovery of iron from waste ferrous sulphate by co-precipitation and magnetic separation 被引量:6
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作者 余旺 彭映林 郑雅杰 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2017年第1期211-219,共9页
Magnetite concentrate was recovered from ferrous sulphate by co-precipitation and magnetic separation. In co-precipitation process, the effects of reaction conditions on iron recovery were studied, and the optimal rea... Magnetite concentrate was recovered from ferrous sulphate by co-precipitation and magnetic separation. In co-precipitation process, the effects of reaction conditions on iron recovery were studied, and the optimal reaction parameters are proposed as follows: n(CaO)/n(Fe2+) 1.4:1, reaction temperature 80 ℃, ferrous ion concentration 0.4 mol/L, and the final mole ratio of Fe3+ to FJ+ in the reaction solution 1.9-2.1. In magnetic separation process, the effects of milling time and magnetic induction intensity on iron recovery were investigated. Wet milling played an important part in breaking the encapsulated magnetic phases. The results showed that the mixed product was wet-milled for 20 min before magnetic separation, the grade and recovery rate of iron in magnetite concentrate were increased from 51.41% and 84.15% to 62.05% and 85.35%, respectively. 展开更多
关键词 ferrous sulphate titanium dioxide magnetite concentrate co-precipitATION wet milling magnetic separation
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Preparation of MnxNi0.5-xZn0.5Fe2O4 Nanorods by the Co-precipitation Method 被引量:2
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作者 李巧玲 常传波 +1 位作者 张巍 张豪 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2010年第6期680-684,745,746,共7页
MnxNi0.5-xZn0.5Fe2O4 nanorods were successfully synthesized by the thermal treatment of rod-like precursors that were fabricated by the co-precipitation of Mn2+, Ni2+, and Fe2+ in the lye. The phase, morphology, an... MnxNi0.5-xZn0.5Fe2O4 nanorods were successfully synthesized by the thermal treatment of rod-like precursors that were fabricated by the co-precipitation of Mn2+, Ni2+, and Fe2+ in the lye. The phase, morphology, and particle diameter were examined by the X-ray diffraction and transmission electron microscopy. The magnetic properties of the samples were studied using a vibrating sample magnetometer. nanorods with a diameter of 35 nm and an The results indicated that pure Ni0.5-xZn0.5Fe2O4 aspect ratio of 15 were prepared. It was found that the diametei of the MnxNi0.5-xZn0.5Fe2O4(0≤x≤0.5) samples increased, the length and the aspect .ratio decreased, with an increase in x value. When x=0.5, the diameter and the aspect ratio of the sample reached up to 50 nm and 7-8, respectively. The coercivity of the samples first increased and then decreased with the increase in the x value. The coercivity of the samples again increased when the x value was higher than 0.4. When x=0.5, the coercivity of the MnxNi0.5-xZn0.5Fe2O4 sample reached the maximal value (134.3 Oe) at the calcination temperature of 600 ℃. The saturation magnetization of the samples first increased and then. decreased with the increase in the x value. When x=0.2, the saturation magnetizat:ion of the sample reached the maximal value (68.5 emu/g) at the calcination temperature of 800 ℃. 展开更多
关键词 MnxNi0.5-xZn0.5Fe2O4 Nanorod co-precipitATION Magnetic property
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Structure and electrochemical performance of delafossite AgFeO_(2)nanoparticles for supercapacitor electrodes
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作者 Choulong Veann Thongsuk Sichumsaeng +3 位作者 Ornuma Kalawa Narong Chanlek Pinit Kidkhunthod Santi Maensiri 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第1期201-213,共13页
Delafossite AgFeO_(2)nanoparticles with a mixture of 2H and 3R phases were successfully fabricated by using a simple co-precipitation method.The resulting precursor was calcined at temperatures of 100,200,300,400,and ... Delafossite AgFeO_(2)nanoparticles with a mixture of 2H and 3R phases were successfully fabricated by using a simple co-precipitation method.The resulting precursor was calcined at temperatures of 100,200,300,400,and 500℃to obtain the delafossite AgFe0_(2)phase.The morphology and microstructure of the prepared AgFeO_(2)samples were characterized by using field emission scanning electron microscopy(FESEM),transmission electron microscopy(TEM),N_(2) adsorption/desorption,X-ray absorption spectroscopy(XAS),and Xray photoelectron spectroscopy(XPS)techniques.A three-electrode system was employed to investigate the electrochemical properties of the delafossite AgFeO_(2)nanoparticles in a 3 M KOH electrolyte.The delafossite AgFeO_(2)nanoparticles calcined at 100℃(AFO100)exhibited the highest surface area of 28.02 m^(2)·g^(-1)and outstanding electrochemical performance with specific capacitances of 229.71 F·g^(-1)at a current density of 1 A·g^(-1)and 358.32 F·g^(-1)at a scan rate of 2 mV·s^(-1).This sample also demonstrated the capacitance retention of 82.99% after 1000 charge/discharge cycles,along with superior specific power and specific energy values of 797.46 W·kg^(-1)and 72.74Wh·kg^(-1),respectively.These findings indicate that delafossite AgFeO_(2)has great potential as an electrode material for supercapacitor applications. 展开更多
关键词 NANOPARTICLES DELAFOSSITE electrochemical properties X-ray absorption spectroscopy co-precipitATION SUPERCAPACITOR
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Preparation of FeCoNi medium entropy alloy from Fe^(3+)-Co^(2+)-Ni^(2+)solution system
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作者 Zongyou Cheng Qing Zhao +3 位作者 Mengjie Tao Jijun Du Xingxi Huang Chengjun Liu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第1期92-101,共10页
In recent years,medium entropy alloys have become a research hotspot due to their excellent physical and chemical performances.By controlling reasonable elemental composition and processing parameters,the medium entro... In recent years,medium entropy alloys have become a research hotspot due to their excellent physical and chemical performances.By controlling reasonable elemental composition and processing parameters,the medium entropy alloys can exhibit similar properties to high entropy alloys and have lower costs.In this paper,a FeCoNi medium entropy alloy precursor was prepared via sol-gel and coprecipitation methods,respectively,and FeCoNi medium entropy alloys were prepared by carbothermal and hydrogen reduction.The phases and magnetic properties of FeCoNi medium entropy alloy were investigated.Results showed that FeCoNi medium entropy alloy was produced by carbothermal and hydrogen reduction at 1500℃.Some carbon was detected in the FeCoNi medium entropy alloy prepared by carbothermal reduction.The alloy prepared by hydrogen reduction was uniform and showed a relatively high purity.Moreover,the hydrogen reduction product exhibited better saturation magnetization and lower coercivity. 展开更多
关键词 medium entropy alloy SOL-GEL co-precipitATION carbothermal hydrogen reduction
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Fluorescence and preparation of Sr_2(P_2O_7 ):Ce,Tb phosphate by co-precipitation method 被引量:8
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作者 Cheng-Guo Ma Wei Zheng +1 位作者 Li-Guo Jin Li-Min Dong 《Rare Metals》 SCIE EI CAS CSCD 2013年第4期420-424,共5页
The micron-sized Sr2(P2OT):Ce,Tb green phosphors were prepared by being annealed at different temperatures with its precursors synthesized by co-pre-cipitates of (NH4)2HPO4 at ambient temperature. The phase struc... The micron-sized Sr2(P2OT):Ce,Tb green phosphors were prepared by being annealed at different temperatures with its precursors synthesized by co-pre-cipitates of (NH4)2HPO4 at ambient temperature. The phase structure, grain size, surface morphology, and luminescent properties of phosphors were investigated by X-ray diffraction, scanning electron microscope, trans-mission electron microscope, and fluorescence spectrum. The results show that the product of precursor annealed at 1,100 ℃ is Sr2(P2O7):Ce,Tb, which belongs to ortho-rhombic phase. The powder is spherical and the size dis-tribution is in micron grade. The sample with the molar ratio of Sr/Tb/Ce of 100.0:0.4:0.6 shows the best fluores-cence effect annealed at 1,100 ℃ for 3 h. The phosphors produce green fluorescence by being excitated with ultra-violet radiation of 254 nm wavelength, and the main emission peak is at 547 nm. The Sr2(P2O7):Ce,Tb phos-phors synthesized by co-precipitation method of precursors at ambient temperature is a kind of efficient green-emitting phosphors. 展开更多
关键词 PHOSPHORS co-precipitation method Rareearth phosphate PHOSPHORESCENCE
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Electrochemical performance of Ti^(4+)-doped LiFePO_4 synthesized by co-precipitation and post-sintering method 被引量:10
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作者 伍凌 王志兴 +4 位作者 李新海 李灵均 郭华军 郑俊超 王小娟 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第5期814-818,共5页
Ti4+-mixed FePO4·xH2O precursor was prepared by co-precipitation method,with which Ti4+ cations were added in the process of preparing FePO4·xH2O to pursue an effective and homogenous doping way.Ti4+-doped L... Ti4+-mixed FePO4·xH2O precursor was prepared by co-precipitation method,with which Ti4+ cations were added in the process of preparing FePO4·xH2O to pursue an effective and homogenous doping way.Ti4+-doped LiFePO4 was prepared by an ambient-reduction and post-sintering method using the as-prepared precursor,Li2CO3 and oxalic acid as raw materials.The samples were characterized by scanning electron microscopy (SEM),X-ray diffractometry (XRD),electrochemical impedance spectroscopy (EIS),and electrochemical charge/discharge test.Effects of Ti4+-doping and sintering temperature on the physical and electrochemical performance of LiFePO4 powders were investigated.It is noted that Ti4+-doping can improve the electrochemical performance of LiFePO4 remarkably.The Ti4+-doped sample sintered at 600 ℃ delivers an initial discharge capacity of 150,130 and 125 mA·h/g with 0.1C,1C and 2C rates,respectively,without fading after 40 cycles. 展开更多
关键词 lithium-ion battery cathode material LIFEPO4 Ti4+-doping co-precipitATION
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Oxidative coupling of methane over LaAlO3 perovskite catalysts prepared by a co-precipitation method: Effect of co-precipitation pH value 被引量:5
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作者 Yujin Sim Jihoon Yoo +1 位作者 Jeong-Myeong Ha Ji Chul Jung 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2019年第8期1-8,I0001,共9页
Oxidative coupling of methane(OCM) was conducted over LaAlO3X catalysts that were prepared by a coprecipitation method using different co-precipitation pH values(X = 6–10). The aim is to investigate the effect of p H... Oxidative coupling of methane(OCM) was conducted over LaAlO3X catalysts that were prepared by a coprecipitation method using different co-precipitation pH values(X = 6–10). The aim is to investigate the effect of p H values on the catalytic activity of La AlO3 catalysts in this reaction. The results showed that the co-precipitation pH value affected greatly on the formation of chemical species of precipitate precursors in the co-precipitation step, leading to different phases of the finally obtained LaAlO3 catalysts.When the co-precipitation pH value increased up to 8, the lanthanum-related phases such as La2 O3 and La(OH)3 were gradually formed as by-products, preventing the formation of LaAlO3 perovskite crystalline structure and facilitating the formation of oxygen vacancies on catalyst surface. However, at pH value of9 or higher, the lanthanum content in the precipitate precursor was increased greatly. Not LaAlO3 perovskite but lanthanum-related phases were developed as main phases, reducing their catalytic activities in this reaction. Among LaAlO3 catalysts, the one prepared at pH = 8 showed the highest C2 yield due to its well-developed oxygen vacancies and electrophilic lattice oxygen. Therefore, the co-precipitation pH value strongly affected the LaAlO3 catalyst activity in OCM reaction. A precious pH control should be required to prepare various perovskite catalysts for the OCM. 展开更多
关键词 LAALO3 PEROVSKITE OXIDATIVE coupling of METHANE co-precipitATION pH value
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Solution-Phase Synthesis and Characterization of Perovskite LaCoO_3 Nanocrystals via A Co-Precipitation Route 被引量:3
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作者 朱俊武 孙小杰 +3 位作者 王艳萍 汪信 杨绪杰 陆路德 《Journal of Rare Earths》 SCIE EI CAS CSCD 2007年第5期601-604,共4页
A facile co-precipitation route for the synthesis of well-dispersed LaCoO3 nanocrystals was developed. The asprepared products were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM),... A facile co-precipitation route for the synthesis of well-dispersed LaCoO3 nanocrystals was developed. The asprepared products were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), energy dispersive X-ray spectrometer (EDX), and laser Raman spectroscopy (LRS). The resuks showed that modulating the growth parameters, such as the addition of surfactants as well as the adding manner of the precipitator had a significant effect on the overall shape and size of the obtained nanocrystals. The nanorods with the diameter of 20 nm and spherical LaCoO3 nanocrystals with the size of about 25 nm could be obtained at a relatively low calcining temperature of 600℃. Furthermore, the Raman properties of LaCoO3 products obtained at different calcining temperatures were investigated. 展开更多
关键词 PEROVSKITE LACOO3 co-precipitATION NANOCRYSTALS rare earths
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Effects of synthesis conditions on the structural and electrochemical properties of layered LiNi_(1/3)Co_(1/3)Mn_(1/3)O_2 cathode material via oxalate co-precipitation method 被引量:6
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作者 TIAN Hua YE Naiqing +1 位作者 LIU Dan LI Wenqun 《Rare Metals》 SCIE EI CAS CSCD 2008年第6期575-579,共5页
The uniform layered LiNi1/3Co1/3Mn1/3O2 cathode material for lithium ion batteries was prepared by using (Ni1/3Co1/3Mn1/3)C2O4 as precursor synthesized via oxalate co-precipitation method in air. The effects of calc... The uniform layered LiNi1/3Co1/3Mn1/3O2 cathode material for lithium ion batteries was prepared by using (Ni1/3Co1/3Mn1/3)C2O4 as precursor synthesized via oxalate co-precipitation method in air. The effects of calcination temperature and time on the structure and electrochemical properties of the LiNi1/3Co1/3Mn1/3O2 were systemically studied. XRD results revealed that the optimal calcination conditions to prepare the layered LiNi1/3Co1/3Mn1/302 were 950℃ for 15 h. Electrochemical measurement showed that the sample prepared under the such conditions has the highest initial discharge capacity of 160.8 mAh/g and the smallest irreversible capacity loss of 13.5% as well as stable cycling performance at a constant current density of 30 mA/g between 2.5 and 4.3 V versus Li at room temperature. 展开更多
关键词 lithium ion batteries oxalate co-precipitation method cathode materials electrochemical performance
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Adaptation fermentation of Pichia stipitis and combination detoxification on steam exploded lignocellulosic prehydrolyzate 被引量:2
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作者 Jun-Jun Zhu Qiang Yong +2 位作者 Yong Xu Shang-Xing Chen Shi-Yuan Yu 《Natural Science》 2009年第1期47-54,共8页
Yeast Pichia stipitis CBS 5776 was developed through adaptation fermentation step by step in steam exploded corn stover prehydrolyzate because high concentration of weak acids and other inhibitors present in the prehy... Yeast Pichia stipitis CBS 5776 was developed through adaptation fermentation step by step in steam exploded corn stover prehydrolyzate because high concentration of weak acids and other inhibitors present in the prehydrolyzate could degrade the fermentability. However, the adaptability of Pichia stipitis CBS 5776 in the prehydrolyzate was so limited that steam strip-ping and overliming were applied to remove these inhibitors from it. Corn stover was steam exploded;the filtrate of steam exploded corn stover was hydrolyzed with dilute sulfuric acid, and then the acid hydrolyzate was detoxified and fermented by Pichia stipitis CBS 5776. Steam stripping could remove volatile com-pounds from the acid hydrolyzate and the fil-trate. At a steam stripping time of 120min, 81% acetic acid and 59% formic acid were removed from the acid hydrolyzate, 77% acetic acid and 45% formic acid were removed from the filtrate, while furfural was stripped off completely from the acid hydrolyzate and the filtrate. Overliming could reduce the contents of furfural and phe-nolics present in the acid hydrolyzate, however, sugars, especially pentoses, were also removed partially. It was necessary to detoxify the acid hydrolyzate in order to ferment the sugars to ethanol. Acid hydrolyzate detoxified with a combination of steam stripping for 120 min and overliming at pH11 and 60℃ for 90 min, its fer-mentability was significantly improved. Xylose was consumed nearly completely in 24h with an ethanol yield of 15.92g/l, 80.34% of theoretical. 展开更多
关键词 STEAM Explosion STEAM STRIPPING Overliming Inhibitor Acid hydrolyzATE
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