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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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Synthesis and Photoluminescence of BaMgAl_(10)O_(17)∶Eu^(2+) Phosphor by Oxalate Co-precipitation Process 被引量:1
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作者 张占辉 王育华 +1 位作者 都云昆 李峰 《Journal of Rare Earths》 SCIE EI CAS CSCD 2005年第4期401-405,共5页
Single phase of Ba1-x MgAl10O17 : x Eu^2+ (0.02≤ x ≤ 0. 14) phosphors was first successfully prepared by coprecipitation in aqueous medium with a “reverse strike” method, using oxalic acid and ammonia together... Single phase of Ba1-x MgAl10O17 : x Eu^2+ (0.02≤ x ≤ 0. 14) phosphors was first successfully prepared by coprecipitation in aqueous medium with a “reverse strike” method, using oxalic acid and ammonia together as precipitants. Completely crystallized phosphors were obtained at 1300 ℃, which is 300 ℃ lower than the temperature of solid-state reaction. Their photoluminescence was investigated under UV and VUV region, respectively. The emission spectra of Ba1-x MgAl10O17:xEu^2+ samples excited by 254 or 147 nm showed a characteristic wide band with the peak centred at about 450 454 nm. Optimum emission intensity reached at x = 0.1 and then concentration quenching occurred. The synthesized phosphor shows 10% higher emission intensity than that prepared by solid-state reaction. 展开更多
关键词 BaMgAl10O17:Eu^2+ PHOSPHOR oxalate co-precipitation process reverse strike
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Oxalate regulates crystal-cell adhesion and macrophage metabolism via JPT2/PI3K/AKT signaling to promote the progression of kidney stones
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作者 Qianlin Song Chao Song +8 位作者 Xin Chen Yunhe Xiong Ziqi He Xiaozhe Su Jiawei Zhou Hu Ke Caitao Dong Wenbiao Liao Sixing Yang 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2024年第6期851-862,共12页
Oxalate is an organic dicarboxylic acid that is a common component of plant foods.The kidneys are essential organs for oxalate excretion,but excessive oxalates may induce kidney stones.Jupiter microtubule associated h... Oxalate is an organic dicarboxylic acid that is a common component of plant foods.The kidneys are essential organs for oxalate excretion,but excessive oxalates may induce kidney stones.Jupiter microtubule associated homolog 2(JPT2)is a critical molecule in Ca^(2+)mobilization,and its intrinsic mechanism in oxalate exposure and kidney stones remains unclear.This study aimed to reveal the mechanism of JPT2 in oxalate exposure and kidney stones.Genetic approaches were used to control JPT2 expression in cells and mice,and the JPT2 mechanism of action was analyzed using transcriptomics and untargeted metabolomics.The results showed that oxalate exposure triggered the upregulation of JPT2,which is involved in nicotinic acid adenine dinucleotide phosphate(NAADP)-mediated Ca^(2+)mobilization.Transcriptomic analysis revealed that cell adhesion and macrophage inflammatory polarization were inhibited by JPT2 knockdown,and these were dominated by phosphatidylinositol 3-kinase(PI3K)/AKT signaling,respectively.Untargeted metabolomics indicated that JPT2 knockdown inhibited the production of succinic acid semialdehyde(SSA)in macrophages.Furthermore,JPT2 deficiency in mice inhibited kidney stones mineralization.In conclusion,this study demonstrates that oxalate exposure facilitates kidney stones by promoting crystal-cell adhesion,and modulating macrophage metabolism and inflammatory polarization via JPT2/PI3K/AKT signaling. 展开更多
关键词 oxalate Kidney stones JPT2 Crystal-cell adhesion IMMUNOREGULATION
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Genome Sequencing,Probiotic Analysis,and Oxalate Degradation Modification of Limosilactobacillus reuteri Q35
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作者 NIU Dong-Yu KONG Ling-Hui +1 位作者 LIU Xiang-Yong QIN Jia-Yang 《中国生物化学与分子生物学报》 CAS CSCD 北大核心 2024年第11期1585-1595,共11页
Limosilactobacillus reuteri is a microbe intricately linked to humans and animal health.A thorough assessment of its safety and potential benefits is imperative prior to its application in human and animals.In this in... Limosilactobacillus reuteri is a microbe intricately linked to humans and animal health.A thorough assessment of its safety and potential benefits is imperative prior to its application in human and animals.In this investigation,we performed a comprehensive analysis encompassing genome sequencing,genomic analysis,and phenotypic characterization of L.reuteri Q35,an exceptionally proficient producer of reuterin.The whole genome sequencing results showed that the complete genome sequence spans 2145158 bp with a GC content of 38.9%and encompasses 2121 genes.Initial identification of antibiotic-resistant genes,virulence factors,and toxin-coding genes in the genome substantiated the strain’s low-risk status.Subsequent tests for antibiotic resistance,acute oral toxicology,and hemolysis further confirmed its elevated safety level.The genome of L.reuteri Q35 was found to contain genes associated with adhesion and stress tolerance.Following exposure to artificial gastric juice and bile salt,the strain exhibited a higher survival rate and demonstrated a strong scavenging ability for hydroxyl free radicals in antioxidant capacity tests.These findings suggested that L.reuteri Q35 possesses unique probiotic properties.Additionally,the genome of strain Q35 harbors three truncated oxaloyl-CoA decarboxylase genes(oxc1,oxc2 and oxc3),overexpression of which resulted in a significant increase in ammonium oxalate degradation from 29.5%to 48.8%.These findings highlight that L.reuteri Q35 exhibits both favorable safety characteristics alongside beneficial properties,making it a promising candidate for treating metabolic disorders such as hyperoxaluria. 展开更多
关键词 Limosilactobacillus reuteri genomic analysis SAFETY probiotic oxalate degradation
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Dimethylamine oxalate manipulating CsPbI_(3) perovskite film crystallization process for high efficiency carbon electrode based perovskite solar cells
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作者 Wenran Wang Xin Peng +7 位作者 Jianxin Zhang Jiage Lin Rong Huang Guizhi Zhang Huishi Guo Zhenxiao Pan Xinhua Zhong Huashang Rao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期221-228,I0006,共9页
Crystallization process determines the quality of perovskite films and the performances of resultant perovskite solar cells(PSCs).Dimethylamine oxalate has been proven as a multifunctional modulator,and is explored as... Crystallization process determines the quality of perovskite films and the performances of resultant perovskite solar cells(PSCs).Dimethylamine oxalate has been proven as a multifunctional modulator,and is explored as an efficient additive in manipulating the crystallization process of CsPbI_(3) perovskite films.On one hand,oxalate serves as the precipitator that facilitates the nucleation process of intermediate.The larger size of intermediate is conductive to the larger size and smaller grain boundaries of resultant perovskite.On the other hand,in subsequent annealing process,the phase conversion and growth process of transient perovskite can be decelerated due to the strong interactions of oxalate with both dimethylamine cation(DMA^(+))and Pb^(2+).Due to the optimized crystallization kinetics,the morphology and quality of CsPbI_(3) perovskite films are comprehensively improved with lower defect concentrations,and charge recombination loss is effectively suppressed.Benefiting from the optimized crystal quality of perovskite films,the carbon electrode-based CsPbI_(3) PSCs exhibit a champion efficiency of 18.48%.This represents one of the highest levels among all hole transport layer-free inorganic perovskite solar cells. 展开更多
关键词 Solar cells PEROVSKITE CsPbI_(3) Carbon electrodes oxalate
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Tuning the product selectivity of dimethyl oxalate hydrogenation over WO_(x) modified Cu/SiO_(2) catalysts
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作者 Zheng Li Zhuo Ma +9 位作者 Yihui Li Ziang Zhao Yuan Tan Ziyin Liu Xingkun Chen Nian Lei Huigang Wang Wei Lu Hejun Zhu Yunjie Ding 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第10期128-138,I0004,共12页
Product selectivity and reaction pathway are highly dependent on surface structure of heterogeneous catalysts.For vapor-phase hydrogenation of dimethyl oxalate(DMO),"EG route"(DMO→methyl glycolate(MG)ethyle... Product selectivity and reaction pathway are highly dependent on surface structure of heterogeneous catalysts.For vapor-phase hydrogenation of dimethyl oxalate(DMO),"EG route"(DMO→methyl glycolate(MG)ethylene glycol(EG)→ethanol(ET))and"MA route"(DMO→MG→methyl acetate(MA))were proposed over traditional Cu based catalysts and Mo-based or Fe-based catalysts,respectively.Herein,tunable yield of ET(93.7%)and MA(72.1%)were obtained through different reaction routes over WO_(x) modified Cu/SiO_(2) catalysts,and the corresponding reaction route was further proved by kinetic study and in-situ DRIFTS technology.Mechanistic studies demonstrated that H_(2) activation ability,acid density and Cu-WO_(x) interaction on the catalysts were tuned by regulating the surface W density,which resulted in the different reaction pathway and product selectivity.What's more,high yield of MA produced from DMO hydrogenation was firstly reported with the H_(2) pressure as low as 0.5 MPa. 展开更多
关键词 ETHANOL Dimethyl oxalate Selective hydrogenation Methyl acetate WCu/SiO_(2)catalyst
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Severe acute kidney injury due to oxalate crystal induced severe interstitial nephritis:A case report
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作者 Maulik K Lathiya Praveen Errabelli +1 位作者 Sasmit Roy Neeharik Mareedu 《World Journal of Nephrology》 2024年第2期24-30,共7页
BACKGROUND Acute kidney injury(AKI)due to interstitial nephritis is a known condition primarily attributed to various medications.While medication-induced interstitial nephritis is common,occurrences due to non-pharma... BACKGROUND Acute kidney injury(AKI)due to interstitial nephritis is a known condition primarily attributed to various medications.While medication-induced interstitial nephritis is common,occurrences due to non-pharmacological factors are rare.This report presents a case of severe AKI triggered by intratubular oxalate crystal deposition,leading to interstitial nephritis.The aim is to outline the case and its management,emphasizing the significance of recognizing uncommon causes of interstitial nephritis.CASE SUMMARY A 71-year-old female presented with stroke-like symptoms,including weakness,speech difficulties,and cognitive impairment.Chronic hypertension had been managed with hydrochlorothiazide(HCTZ)for over two decades.Upon admis-sion,severe hypokalemia and AKI were noted,prompting discontinuation of HCTZ and initiation of prednisolone for acute interstitial nephritis.Further investigations,including kidney biopsy,confirmed severe acute interstitial nephritis with oxalate crystal deposits as the underlying cause.Despite treatment,initial renal function showed minimal improvement.However,with prednisolone therapy and supportive measures,her condition gradually improved,high-lighting the importance of comprehensive management.CONCLUSION This case underscores the importance of a thorough diagnostic approach in identifying and addressing uncommon causes of interstitial nephritis.The occurrence of interstitial nephritis due to oxalate crystal deposition,especially without typical risk factors,emphasizes the need for vigilance in clinical practice. 展开更多
关键词 Acute kidney injury Interstitial nephritis oxalate crystal HYDROCHLOROTHIAZIDE HYPOKALEMIA Case report
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Insights into kinetics and reaction mechanism of acid-catalyzed transesterification synthesis of diethyl oxalate
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作者 Naiwen Zhang Rui Xia +4 位作者 Siyu Wan Xinyang Xiong Jinggang Zhao Jun Zhou Lei Shi 《Resources Chemicals and Materials》 2024年第1期93-101,共9页
The catalytic performance of different acidic catalysts for diethyl oxalate synthesis from the one-step transesterification of dimethyl oxalate and ethanol was evaluated.The effects of different factors(e.g.,acidity,e... The catalytic performance of different acidic catalysts for diethyl oxalate synthesis from the one-step transesterification of dimethyl oxalate and ethanol was evaluated.The effects of different factors(e.g.,acidity,electron accepting capacity,cations type and crystalline water)on the catalytic activity of acidic catalysts were investigated respectively.It was proposed and confirmed that the transesterification reaction catalyzed by a Lewis acid(FeCl3)and a Bronsted acid(H2SO4)follows a first-order kinetic reaction process.In addition,the Lewis acid-catalyzed transesterification processes with different ester structures were used to further explore and understand the speculated reaction mechanism.This work enriches the theoretical understanding of acid-catalyzed transesterification reactions and is of great significance for the development of highly active catalysts for diethyl oxalate synthesis,diminishing the industrial production cost of diethyl oxalate,and developing downstream bulk or high-value-added industrial products. 展开更多
关键词 Diethyl oxalate TRANSESTERIFICATION KINETICS Acidic catalyst Reaction mechanism
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Kinetics of thermal decomposition of lanthanum oxalate hydrate 被引量:11
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作者 詹光 余军霞 +2 位作者 徐志高 周芳 池汝安 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第4期925-934,共10页
Lanthanum oxalate hydrate La2(C2O4)3·10H2O,the precursor of La2O3 ultrafine powders,was prepared by impinging stream reactor method with PEG 20000 as surfactant.Thermal decomposition of La2(C2O4)3·10H2O ... Lanthanum oxalate hydrate La2(C2O4)3·10H2O,the precursor of La2O3 ultrafine powders,was prepared by impinging stream reactor method with PEG 20000 as surfactant.Thermal decomposition of La2(C2O4)3·10H2O from room temperature to 900 °C was investigated and intermediates and final solid products were characterized by FTIR and DSC-TG.Results show that the thermal decomposition process consists of five consecutive stage reactions.Flynn-Wall-Ozawa(FWO) and Kissinger-Akahira-Sunose(KAS) methods were implemented for the calculation of energy of activation(E),and the results show that E depends on α,demonstrating that the decomposition reaction process of the lanthanum oxalate is of a complex kinetic mechanism.The most probable mechanistic function,G(α)=[1-(1+α)1/3]2,and the kinetic parameters were obtained by multivariate non-linear regression analysis method.The average E-value that is compatible with the kinetic model is close to value which was obtained by FWO and KAS methods.The fitting curve matches the original TG curve very well. 展开更多
关键词 lanthanum oxalate decahydrate TG-DSC thermal decomposition multivariate non-linear regression analysis
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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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Synthesis and Luminescence Property of Hierarchical Europium Oxalate Micropaticles
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作者 祝玮 张悠金 +1 位作者 何红梅 方智勇 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2011年第1期65-69,I0003,I0004,共7页
Hierarchical europium oxalate Eu2(C2O4)3.10H2O micro-particles were synthesized through a simple precipitation method at room temperature in present of trisodium citrate. The products were characterized by X-ray dif... Hierarchical europium oxalate Eu2(C2O4)3.10H2O micro-particles were synthesized through a simple precipitation method at room temperature in present of trisodium citrate. The products were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, field-emission scanning electron microscopy, and photoluminescence. The possible formation mechanism of the hierarchical europium oxalate Eu2(C2O4)3.10H2O micro-particles was discussed. 展开更多
关键词 HIERARCHY Europium oxalate Precipitation method PHOTOLUMINESCENCE
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Synthesis of Methyl Glycolate by Hydrogenation of Dimethyl Oxalate over Cu-Ag/SiO_2 Catalyst 被引量:26
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作者 Baowei Wang Qian Xu Hua Song Genhui Xu 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2007年第1期78-80,共3页
Methyl glycolate is a good solvent and can be used as feedstock for the synthesis of some important organic chemicals. Catalytic hydrogenation of dimethyl oxalate (DMO) over copper-silver catalyst supported on silic... Methyl glycolate is a good solvent and can be used as feedstock for the synthesis of some important organic chemicals. Catalytic hydrogenation of dimethyl oxalate (DMO) over copper-silver catalyst supported on silica was studied. The Cu-Ag/SiO2 catalyst supported on silica sol was prepared by homogeneous deposition-precipitation of the mixture of aqueous euprammonia complex and silica sol. The proper active temperature of Cu-Ag/SiO2 catalyst for hydrogenation of DMO was 523-623 K. The most preferable reaction conditions for methyl glycolate (MG) were optimized: temperature at 468-478 K, 40-60 mesh catalyst diameter, H2/DMO ratio 40, and 1.0 h^-1 of LHSV. 展开更多
关键词 dimethyl oxalate methyl glycolate ethylene glycol HYDROGENATION Cu-Ag/SiO2 catalyst
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Effect of copper loading on texture,structure and catalytic performance of Cu/SiO_2 catalyst for hydrogenation of dimethyl oxalate to ethylene glycol 被引量:14
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作者 Bo Zhang Shengguo Hui +3 位作者 Suhua Zhang Yang Ji Wei Li Dingye Fang 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2012年第5期563-570,共8页
Cu/SiO2 catalysts prepared by a convenient and efficient method using the urea hydrolysis deposition-precipitation (UHDP) technique have been proposed focusing on the effect of copper loading.The texture,structure a... Cu/SiO2 catalysts prepared by a convenient and efficient method using the urea hydrolysis deposition-precipitation (UHDP) technique have been proposed focusing on the effect of copper loading.The texture,structure and composition are systematically characterized by ICP,FTIR,N 2-physisorption,N2O chemisorption,TPR,XRD and XPS.The formation of copper phyllosilicate is observed in Cu/SiO2 catalyst by adopting UHDP method,and the amount of copper phyllosilicate is related to copper loading.It is found the structure properties and catalytic performance is profoundly affected by the amount of copper phyllosilicate.The excellent catalytic activity is attributed to the synergetic effect between Cu0 and Cu +.DMO conversion and EG selectivity are determined by the amount of Cu0 and Cu+,respectively.The proper copper loading (30 wt%) provides with the highest ratio of Cu + /Cu0,giving rise to the highest EG yield of 95% under the reaction conditions of p=2.0 MPa,T=473 K,H2/DMO=80 and LHSV=1.0h-1. 展开更多
关键词 CU/SIO2 copper loading dimethyl oxalate ethylene glycol copper phyllosilicate
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Removal of iron from ilmenite by KOH leaching-oxalate leaching method 被引量:5
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作者 WANG Yuanbo QI Tao +1 位作者 CHU Jinglong ZHAO Wei 《Rare Metals》 SCIE EI CAS CSCD 2010年第1期9-15,共7页
Oxalic acid was used for the removal of iron from the intermediates of ilmenite leached by KOH liquor. Various parameters, such as pH, temperature, initial oxalate concentration, and illumination were investigated. Me... Oxalic acid was used for the removal of iron from the intermediates of ilmenite leached by KOH liquor. Various parameters, such as pH, temperature, initial oxalate concentration, and illumination were investigated. Meanwhile, it was found that orthorhombic crystal Ti2O2(OH)2(C2O4)-H2O formed as the leaching proceeded. Scanning electronic microscope (SEM) images implied that the formation of Ti2O2(OH)2(C2O4).H2O with good crystallinity proceeded through three stages. Calcining Ti2O2(OH)2(C2O4)·H2O, anatase (350℃) or mtile (550℃) type TiO2 was obtained, respectively. Element analysis found that the calcined product contained 94.9% TiO2 and 2.5% iron oxide, but only about 1600 ppm dissolvable iron oxide was left, which indicates that oxalic acid was comparatively effective on iron oxide removal from the intermediates. Finally, an improved route was proposed for the upgrading of ilmenite into mtile. 展开更多
关键词 ILMENITE iron removal titanium oxide oxalate potassium hydroxide KOH leaching
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Synthesis of Y_2O_3 Nano-Powder from Yttrium Oxalate under Ambient Temperature 被引量:9
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作者 李玲 《Journal of Rare Earths》 SCIE EI CAS CSCD 2005年第3期358-361,共4页
High purity Y_2O_3 nano-powders was synthesized directly from solution ofindustrial YCl_3 by method of oxalate precipitation through super-micro-reactors made by complexnon-ionic surfactant. The purity and diameter of... High purity Y_2O_3 nano-powders was synthesized directly from solution ofindustrial YCl_3 by method of oxalate precipitation through super-micro-reactors made by complexnon-ionic surfactant. The purity and diameter of Y_2O_3 particles were controlled by such processingparameters as concentration of YCl_3 and oxalic acid and complex non-ionic surfactant etc. TEMphotomicrographs show that Y_2O_3 particles are spherical in shape, with an average diameter of lessthan 30 nm. Test results certify that the purity and particle diameter as well as the dispersion ofY_2O_3 nano-powder depend on the concentrations of YCl_3, oxalic acid and complex non-ionicsurfactant. The optimum ranges of the concentrations for YCl_3 and complex non-ionic surfactant whenthe diameter of Y_2O_3 particles is smaller than 100 nm are 0.43 ~1.4 mol ? L^(-1) and0.031~0.112 mol·L^(-1) respectively, while the mass fraction range of oxalic acid is 10% ~18% .The purity of Y_2O_3 nano-powder tested by ICP-AES analysis is 99.99% . 展开更多
关键词 oxalate precipitation method complex non-ionic surfactant super-micro-reactor Y_2O_3 nano-powder synthesis rare earths
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Sclerotinia sclerotiorum virulence is affected by mycelial age via reduction in oxalate biosynthesis 被引量:3
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作者 WANG Ji-peng XU You-ping +2 位作者 ZANG Xian-peng LI Shuang-sheng CAI Xin-zhong 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第5期1034-1045,共12页
Sclerotinia sclerotiorum is one of the most devastating necrotrophic phytopathogens. Virulence of the hyphae of this fungus at different ages varies significantly. Molecular mechanisms underlying this functional disti... Sclerotinia sclerotiorum is one of the most devastating necrotrophic phytopathogens. Virulence of the hyphae of this fungus at different ages varies significantly. Molecular mechanisms underlying this functional distinction are largely unknown. In this study, we confirmed the effect of mycelial culture time/age on virulence in two host plants and elucidated its molecular and morphological basis. The virulence of the S. sclerotiorum mycelia in plants dramatically decreases along with the increase of the mycelial age. Three-day-old mycelia lost the virulence in plants. Comparative proteomics analyses revealed that metabolism pathways were comprehensively reprogrammed to suppress the oxalic acid(OA) accumulation in old mycelia. The oxaloacetate acetylhydrolase(OAH), which catalyzes OA biosynthesis, was identified in the S. sclerotiorum genome. Both gene expression and protein accumulation of OAH in old mycelia were strongly repressed. Moreover, in planta OA accumulation was strikingly reduced in old mycelia-inoculated plants compared with young vegetative mycelia-inoculated plants. Furthermore, supply with 10 mmol L^(-1) OA enabled the old mycelia infect the host plants, demonstrating that loss of virulence of old mycelia is mainly caused by being unable to accumulate OA. Additionally, aerial mycelia started to develop from 0.5-day-old vegetative mycelia and dominated over 1-day-old mycelia grown on potato dextrose agar plates. They were much smaller in hypha diameter and grew significantly slower than young vegetative mycelia when subcultured, which did not maintain to progenies. Collectively, our results reveal that S. sclerotiorum aerial hyphae-dominant old mycelia fail to accumulate OA and thereby lose the virulence in host plants. 展开更多
关键词 Sclerotinia sclerotiorum mycelial age oxalic acid VIRULENCE PROTEOMICS
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Modulation of Tartrates with Various Counterions on the Phases of Calcium Oxalate in Gelatinous Systems 被引量:3
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作者 JianMingOUYANG XiangPingLI 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第1期131-134,共4页
Effect of various counterions of tartrate on the crystallization of calcium oxalate in gel system was investigated using scanning electron microscopy and X-ray diffraction. Various tartrates with hydrogen (H2tart), ... Effect of various counterions of tartrate on the crystallization of calcium oxalate in gel system was investigated using scanning electron microscopy and X-ray diffraction. Various tartrates with hydrogen (H2tart), sodium (Na2tart), potassium (K2tart), ammonium ((NH4)2tart), and a mixture of sodium and potassium cations (NaKtart) were considered. For H2tart, Na2tart, and (NH4)2tart, calcium oxalate dihydrate (COD) was induced. However, for K2tart and NaKtart, calcium oxalate trihydrate (COT) was obtained. 展开更多
关键词 Calcium oxalate GEL tartrate.
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Neuroprotective Effect of Escitalopram Oxalate in Rats with Chronic Hypoperfusion 被引量:5
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作者 马莉 卢祖能 +1 位作者 胡沛 姚长江 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2015年第4期514-518,共5页
Summary: The neuroproteetive effects of escitalopram oxalate in rats with chronic hypoperfusion and the possible mechanism were explored. Chronic hypoperfusion (2-VO) model was prepared and given escitalopram oxala... Summary: The neuroproteetive effects of escitalopram oxalate in rats with chronic hypoperfusion and the possible mechanism were explored. Chronic hypoperfusion (2-VO) model was prepared and given escitalopram oxalate (experimental group) or PBS (control group) after 6 weeks. Eight weeks after the operation, Morris water maze test was carried out to evaluate the learning and memory ability of the rats. The cell proliferation, three-dimensional vascular distribution, cell morphological changes in ischemic area and the plasma vascular endothelial growth factor (VEGF) were detected to explore the possible mechanisms. (1) Morris water maze test showed that the escape latency in the experimental group was significantly shorter than in the control group, while the first quadrant swimming time in the experi- mental group was significantly longer than the control group (both P〈0.01). (2) Cerebrovascular confo- cal detection results showed that the inside diameter of capillaries was significantly less in the experi- mental group than in the control group; the vascular density was significantly increased in the experi- mental group and the total area of capillaries was also significantly increased in the experimental group as compared with the control group. (3) There was statistically significant difference in BrdU-positive cells in the ischemic brain tissue between the experimental group and the control group (P=0.003〈0.01). (4) VEGF concentrations in the plasma and the ischemic area were higher in the experimental group than in the control group (P〈0.05). It was concluded that escitalopram oxalate could significantly im- prove the learning and memory ability of the rats with chronic cerebral ischemia probably by the VEGF-mediated angiogenesis. 展开更多
关键词 escitalopram oxalate chronic hypoperfusion NEUROPROTECTION MECHANISM vascular endo- thelial growth factor
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