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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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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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Activation mechanism of ammonium oxalate with pyrite in the lime system and its response to flotation separation of pyrite from arsenopyrite 被引量:3
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作者 Runpeng Liao Shuming Wen +2 位作者 Qicheng Feng Jiushuai Deng Hao Lai 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第2期271-282,共12页
The activation properties of ammonium oxalate on the flotation of pyrite and arsenopyrite in the lime system were studied in this work.Single mineral flotation tests showed that the ammonium oxalate strongly activated... The activation properties of ammonium oxalate on the flotation of pyrite and arsenopyrite in the lime system were studied in this work.Single mineral flotation tests showed that the ammonium oxalate strongly activated pyrite in high alkalinity and high Ca^(2+)system,whereas arsenopyrite was almost unaffected.In mineral mixtures tests,the recovery difference between pyrite and arsenopyrite after adding ammonium oxalate is more than 85%.After ammonium oxalate and ethyl xanthate treatment,the hydrophobicity of pyrite increased significantly,and the contact angle increased from 66.62°to 75.15°and then to 81.21°.After ammonium oxalate treatment,the amount of ethyl xanthate adsorption on the pyrite surface significantly increased and was much greater than that on the arsenopyrite surface.Zeta potential measurements showed that after activation by ammonium oxalate,there was a shift in the zeta potential of pyrite to more negative values by adding xanthate.X-ray photoelectron spectroscopy test showed that after ammonium oxalate treatment,the O 1s content on the surface of pyrite decreased from 44.03%to 26.18%,and the S 2p content increased from 14.01%to 27.26%,which confirmed that the ammonium oxalatetreated pyrite surface was more hydrophobic than the untreated surface.Therefore,ammonium oxalate may be used as a selective activator of pyrite in the lime system,which achieves an efficient flotation separation of S-As sulfide ores under high alkalinity and high Ca2+concentration conditions. 展开更多
关键词 PYRITE ARSENOPYRITE ammonium oxalate flotation separation
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Clinical efficacy and safety of Guipi decoction combined with escitalopram oxalate tablets in patients with depression 被引量:1
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作者 Jia Yu Feng-Quan Xu 《World Journal of Clinical Cases》 SCIE 2023年第29期7017-7025,共9页
BACKGROUND Depression is a widespread mental health condition that requires effective treatment.In the treatment of depression,traditional Chinese medicine(TCM)offers obvious advantages,fewer adverse reactions,and a l... BACKGROUND Depression is a widespread mental health condition that requires effective treatment.In the treatment of depression,traditional Chinese medicine(TCM)offers obvious advantages,fewer adverse reactions,and a lower recurrence rate.AIM To evaluate the clinical benefits of Guipi decoction combined with escitalopram oxalate tablets for individuals with depression.METHODS In total,80 patients diagnosed as having depression were enrolled in the study and divided into either an experimental group or a control group.All of the patients were orally administered escitalopram oxalate tablets.Additionally,the experimental group received Jiajian Guipi decoction and reduced Governor vessel fumigation over 4 wk.TCM syndrome scores,Hamilton depression rating scale(HAM-D)scores,self-rating depression scale(SDS)scores,and Pittsburgh sleep quality index scores were measured for the two groups and compared before and after the treatment.The two groups were monitored for any adverse reactions.RESULTS After 4 wk of treatment,both groups exhibited a significant reduction in TCM syndrome scores compared with their pre-treatment scores(P<0.05).However,the experimental group exhibited significantly lower TCM syndrome scores than the control group(P<0.05).Similarly,the post-treatment SDS and HAM-D-24 scores were significantly lower in both groups than the pre-treatment scores(P<0.05),with the experimental group exhibiting lower scores than the control group(P<0.05).The total treatment efficiency was significantly better in the experimental group(97.14%)than in the control group(77.78%)(P<0.05).Furthermore,after 4 wk of treatment,the Pittsburgh sleep quality index scores for both groups were significantly lower than those before the treatment(P<0.05),with the experimental group exhibiting lower scores than the control group(P<0.05).The incidence of adverse reactions was significantly lower in the experimental group than in the control group(P<0.05).CONCLUSION The combination of Guipi decoction and escitalopram oxalate tablets was found to be an effective and safe treatment for depression.This combination could reduce TCM syndrome scores,improve depressive symptoms,and enhance sleep quality. 展开更多
关键词 Jiajian Guipi decoction Escitalopram oxalate tablets Depressive disorder Sleep quality Traditional Chinese medicine syndromes
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Proposal for pathogenesis-based treatment options to reduce calcium oxalate stone recurrence
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作者 Saeed R.Khan Benjamin K.Canales 《Asian Journal of Urology》 CSCD 2023年第3期246-257,共12页
Objective:Prevalence of kidney stone disease continues to increase globally with recurrence rates between 30%and 50%despite technological and scientific advances.Reduction in recurrence would improve patient outcomes ... Objective:Prevalence of kidney stone disease continues to increase globally with recurrence rates between 30%and 50%despite technological and scientific advances.Reduction in recurrence would improve patient outcomes and reduce cost and stone morbidities.Our objective was to review results of experimental studies performed to determine the efficacy of readily available compounds that can be used to prevent recurrence.Methods: All relevant literature up to October 2020,listed in PubMed is reviewed.Results: Clinical guidelines endorse the use of evidence-based medications,such as alkaline agents and thiazides,to reduce urinary mineral supersaturation and recurrence.However,there may be additional steps during stone pathogenesis where medications could moderate stone risk.Idiopathic calcium oxalate stones grow attached to Randall’s plaques or plugs.Results of clinical and experimental studies suggest involvement of reactive oxygen species and oxidative stress in the formation of both the plaques and plugs.The renin-angiotensin-aldosterone system(RAAS),nicotinamide adenine dinucleotide phosphate(NADPH)oxidase,mitochondria,and NOD-like receptor pyrin domain containing-3(NLRP3)inflammasome have all been implicated at specific steps during stone pathogenesis in animal models.Conclusion: In addition to supersaturation-reducing therapies,the use of anti-oxidants,free radical scavengers,and inhibitors of NADPH oxidase,NLRP3 inflammasome,and RAAS may prove beneficial for stone prevention.Compounds such as statins and angiotensin converting enzyme inhibitors are already in use as therapeutics for hypertension and cardio-vascular disease and have previously shown to reduce calcium oxalate nephrolithiasis in rats.Although clinical evidence for their use in stone prevention in humans is limited,experimental data support they be considered along with standard evidence-based medications and clinical expertise when patients are being counselled for stone prevention. 展开更多
关键词 Kidney stones Calcium oxalate Inflammation INFLAMMASOME SUPERSATURATION Reactive oxygen species Oxidative stress
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Continuous-flow electrosynthesis of urea and oxalic acid by CO_(2)-nitrate reduction and glycerol oxidation
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作者 Shuanglong Zhou Yue Shi +3 位作者 Yu Dai Tianrong Zhan Jianping Lai Lei Wang 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第8期270-281,共12页
Urea and oxalic acid are critical component in various chemical manufacturing industries.However,achieving simultaneous generation of urea and oxalic acid in a continuous-flow electrolyzer is a challenge.Herein,we rep... Urea and oxalic acid are critical component in various chemical manufacturing industries.However,achieving simultaneous generation of urea and oxalic acid in a continuous-flow electrolyzer is a challenge.Herein,we report a continuous-flow electrolyzer equipped with 9-square centime-ter-effective area gas diffusion electrodes(GDE)which can simultaneously catalyze the glycerol oxidation reaction in the anode region and the reduction reaction of CO_(2) and nitrate in the cathode region,producing oxalic acid and urea at both the anode and cathode,respectively.The current density at low cell voltage(0.9 V)remained above 18.7 mA cm^(-2) for 10 consecutive electrolysis cycles(120 h in total),and the Faraday efficiency of oxalic acid(67.1%) and urea(70.9%)did not decay.Experimental and theoretical studies show that in terms of the formation of C-N bond at the cathode,Pd-sites can provide protons for the hydrogenation process of CO_(2) and NO_(3)^(-),Cu-sites can promote the generation of *COOH and Bi-sites can stabilize *COOH.In addition,in terms of glycerol oxidation,the introduction of Cu and Bi into Pd metallene promotes the oxidation of hydroxyl groups and the cleavage of C-C bond in glycerol molecules,respectively. 展开更多
关键词 UREA oxalic acid CO_(2) C-N bond Metallene
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Selective leaching of lithium from spent lithium-ion batteries using sulfuric acid and oxalic acid
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作者 Haijun Yu Dongxing Wang +6 位作者 Shuai Rao Lijuan Duan Cairu Shao Xiaohui Tu Zhiyuan Ma Hongyang Cao Zhiqiang Liu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第4期688-696,共9页
Traditional hydrometallurgical methods for recovering spent lithium-ion batteries(LIBs)involve acid leaching to simultaneously extract all valuable metals into the leachate.These methods usually are followed by a seri... Traditional hydrometallurgical methods for recovering spent lithium-ion batteries(LIBs)involve acid leaching to simultaneously extract all valuable metals into the leachate.These methods usually are followed by a series of separation steps such as precipitation,extraction,and stripping to separate the individual valuable metals.In this study,we present a process for selectively leaching lithium through the synergistic effect of sulfuric and oxalic acids.Under optimal leaching conditions(leaching time of 1.5 h,leaching temperature of 70°C,liquid-solid ratio of 4 mL/g,oxalic acid ratio of 1.3,and sulfuric acid ratio of 1.3),the lithium leaching efficiency reached89.6%,and the leaching efficiencies of Ni,Co,and Mn were 12.8%,6.5%,and 21.7%.X-ray diffraction(XRD)and inductively coupled plasma optical emission spectrometer(ICP-OES)analyses showed that most of the Ni,Co,and Mn in the raw material remained as solid residue oxides and oxalates.This study offers a new approach to enriching the relevant theory for selectively recovering lithium from spent LIBs. 展开更多
关键词 selective leaching oxalic acid sulfuric acid spent lithium-ion batteries
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Determination of Carbon and Nitrogen Isotope Fractions in Tartaric Acid, Oxalic Acid, Glucose and Fructose—National Center of High Technologies of Georgia
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作者 Lamzira Pharulava Levani Eliashvili +1 位作者 Vakhtang Betlemidze Bachana Sulava 《American Journal of Analytical Chemistry》 CAS 2024年第8期229-240,共12页
Tartaric acid, oxalic acid, glucose, and fructose are highly important compounds. A comprehensive study of these substances is fascinating from a scientific perspective. They are key components found in wine, vegetabl... Tartaric acid, oxalic acid, glucose, and fructose are highly important compounds. A comprehensive study of these substances is fascinating from a scientific perspective. They are key components found in wine, vegetables, and fruits. Understanding the isotopic compositions in organic compounds is crucial for comprehending various biochemical processes and the nature of substances present in different natural products. Tartaric acid, oxalic acid, glucose, and fructose are widely distributed compounds, including in vegetables and fruits. Tartaric acid plays a significant role in determining the quality and taste properties of wine, while oxalic acid is also prevalent but holds great interest for further research, especially in terms of carbon isotopic composition. We can unveil the mechanisms of processes that were previously impossible to study. Glucose and fructose are the most common monosaccharides in the hexose group, and both are found in fruits, with sweeter fruits containing higher amounts of these substances. In addition to fruits, wheat, barley, rye, onions, garlic, lentils, peppers, dried fruits, beans, broccoli, cabbage, tomatoes, and other foods are also rich sources of fructose and glucose. To determine the mass fraction of the carbon-13 isotope in these compounds, it is important to study their changes during natural synthesis. These compounds can be modified with a carbon center. According to the existing isotopic analysis method, these compounds are converted into carbon oxide or dioxide [1]. At this point, the average carbon content in the given compound is determined, but information about isotope-modified centers is lost. Dilution may occur through the transfer of other carbon-containing organic compounds in the sample or by dilution with natural carbon or carbon dioxide during the transfer process. This article discusses the possibility of carbon-13 isotope propagation directly in these compounds, both completely modified and modified with individual carbon centers. The literature provides information on determining carbon-13 substance in organic compounds, both with a general approach and for individual compounds [2] [3]. 展开更多
关键词 Tartaric Acid oxalic Acid GLUCOSE FRUCTOSE Mass Spectrum Ion Current Intensity Mass Line Mass Number Molecular and Fragment Ions CARBON Carbon Center
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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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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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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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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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