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Minimizing tin(Ⅱ) oxidation using ethylhydrazine oxalate for high-performance all-perovskite tandem solar cells 被引量:1
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作者 Jianhua Zhang Xufeng Liao +9 位作者 Weisheng Li Yutian Tian Qinyang Huang Yitong Ji Guotang Hu Qingguo Du Wenchao Huang Donghoe Kim Yi-Bing Cheng Jinhui Tong 《Journal of Semiconductors》 2025年第5期88-94,共7页
All-perovskite tandem solar cells(ATSCs) have the potential to surpass the Shockley-Queisser efficiency limit of conventional single-junction devices. However, the performance and stability of mixed tin–lead(Sn–Pb) ... All-perovskite tandem solar cells(ATSCs) have the potential to surpass the Shockley-Queisser efficiency limit of conventional single-junction devices. However, the performance and stability of mixed tin–lead(Sn–Pb) perovskite solar cells(PSCs), which are crucial components of ATSCs, are much lower than those of lead-based perovskites. The primary challenges include the high crystallization rate of perovskite materials and the susceptibility of Sn^(2+) oxidation, which leads to rough morphology and unfavorable p-type self-doping. To address these issues, we introduced ethylhydrazine oxalate(EDO) at the perovskite interface, which effectively inhibits the oxidation of Sn^(2+) and simultaneously enhances the crystallinity of the perovskite. Consequently, the EDO-modified mixed tin-lead PSCs reached a power conversion efficiency(PCE) of 21.96% with high reproducibility. We further achieved a 27.58% efficient ATSCs by using EDO as interfacial passivator in the Sn-Pb PSCs. 展开更多
关键词 mixed tin–lead perovskite solar cells ethylhydrazine oxalate Sn^(2+)oxidation all-perovskite tandem solar cells
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The synthesis of alcohol ether esters through the catalytic hydrogenation of diethyl oxalate in the Cu-Al systems induced by Al_(2)O_(3) properties
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作者 Peng Wu Lina Ma +3 位作者 Yu Zheng Li Luo Lihong Su Juntian Li 《日用化学工业(中英文)》 北大核心 2025年第9期1100-1111,共12页
The structure-performance relationship of Cu/Al_(2)O_(3) catalysts in the hydrogenation of diethyl oxalate(DEO)for the synthesis of alcohol ether esters has been investigated by various characterization techniques inc... The structure-performance relationship of Cu/Al_(2)O_(3) catalysts in the hydrogenation of diethyl oxalate(DEO)for the synthesis of alcohol ether esters has been investigated by various characterization techniques including XRD,XPS,N2O titration,and 27Al MAS-NMR.The results showed that when the crystal configurations of Al_(2)O_(3) were the same,increasing the specific surface area could effectively refine the size of copper nanoparticles(Cu NPs),and ultimately improve the conversion of DEO.Meanwhile,the smaller size ofγ-Al_(2)O_(3)(HSAl and SBAl)loaded Cu NPs promotes the reaction towards the deep hydrogenation to produce ethanol(EtOH)and ethylene glycol(EG).Besides,the larger size of Cu NPs on the surface of amorphous Al_(2)O_(3)(HTAl and SolAl)resulted in a lower conversion rate,where ethyl glycolate(Egly)is the main product.Despite there are differences in Al^(3+)ionic coordination in Al_(2)O_(3) with different crystal structures,the experimental data showed that the differences in Al^(3+)ionic coordination did not significantly affect the catalytic performance in the hydrogenation reaction.The formation of alcohol-ether ester chemicals is critically dependent on the interactions between Cu sites and acidic sites.Among them,EG and EtOH were dehydrated to form 2-ethoxyethanol via the SN2 mechanism,while Egly and EtOH were reacted to form ethyl ethoxyacetate(EEA)via the SN2 mechanism.This study provides a theoretical basis for the optimization of the coal-based glycol processes to achieve a diversified product portfolio. 展开更多
关键词 oxalate hydrogenation alcohol ether esters Cu-Al catalyst SN2 mechanism
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Systematic review of pharmacological,complementary,and alternative therapies for the prevention of calcium oxalate stones
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作者 Christopher Y.Z.Lo Qian Hui Khor +4 位作者 Victor A.Abdullatif Cesar Delgado Yadong Lu Jonathan Katz Roger L.Sur 《Asian Journal of Urology》 2025年第2期169-188,共20页
Objective:Several therapeutic modalities for the prevention of calcium oxalate(CaOx)stones have been studied,but only a select few of these modalities have been incorporated into the American Urological Association gu... Objective:Several therapeutic modalities for the prevention of calcium oxalate(CaOx)stones have been studied,but only a select few of these modalities have been incorporated into the American Urological Association guidelines.Our study aimed to organize and interrogate existing research that may be promising for CaOx prevention.Methods:A literature search was conducted using MEDLINE and Embase from inception to November 16,2022.Our study population included adults with or without a history of CaOx kidney stones.Studies in which patients were treated with pharmacotherapies,herbal supplements,or uncategorized research chemicals that are not included in the current American Urological Association guidelines for preventing CaOx stones were included.Nonoriginal research was excluded.Results:Out of the 6155 identified articles,38 were included in the final analysis.The five distinct categories of interventions for stone prevention were“medications”,“herbal supplements”,“food and macronutrients”,“micronutrients”,and“enzymes and probiotics”.Modalities that were found to reduce known urinary risk factors were tolvaptan,cranberry juice,magnesium citrate,oxalate-degrading enzyme ALLN-177,and malic acid.Prophylaxis that reduced stone formation were sodium-glucose cotransporter-2 inhibitors,eicosapentaenoic acid,ethane-1-hydroxy-1,1-disphosphonate.Therapies that reduced urinary risk factors and stone formation were Phyllanthus niruri,rice bran,and magnesium hydroxide.Conclusion:Several of the identified therapies may provide prophylactic benefits for CaOx stone formation and may be useful for inclusion in guidelines for kidney stone prevention. 展开更多
关键词 Calcium oxalate Kidney stone UROLITHIASIS PREVENTION PROPHYLAXIS
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Genomic insights into oxalate content in spinach:A genome-wide association study and genomic prediction approach
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作者 Haizheng Xiong Kenani Chiwina +6 位作者 Waltram Ravelombola Yilin Chen Ibtisam Alatawi Qun Luo Theresa Makawa Phiri Beiquan Mou Ainong Shi 《Horticultural Plant Journal》 2025年第3期1140-1151,共12页
Oxalate content in spinach is a key trait of interest due to its relevance to human health.Understanding the genetic basis of it can facilitate the development of spinach varieties with reduced oxalate levels.In pursu... Oxalate content in spinach is a key trait of interest due to its relevance to human health.Understanding the genetic basis of it can facilitate the development of spinach varieties with reduced oxalate levels.In pursuit of understanding the genetic determinants,a diverse panel comprising 288 spinach accessions underwent thorough phenotyping of oxalate content and were subjected to whole-genome resequencing,resulting in a comprehensive dataset encompassing 14386 single-nucleotide polymorphisms(SNPs).Leveraging this dataset,we conducted a genome-wide association study(GWAS)to identify noteworthy SNPs associated with oxalate content.Furthermore,we employed genomic prediction(GP)via cross-prediction,utilizing five GP models,to assess genomic estimated breeding values(GEBVs)for oxalate content.The observed normal distribution and the wide range of oxalate content,exceeding 600.0 mg$100 g^(-1),underscore the complex and quantitative nature of this trait,likely influenced by multiple genes.Additionally,our analysis revealed distinct stratification,delineating the population into four discernible subpopulations.Furthermore,GWAS analysis employing five models in GAPIT 3 and TASSEL 5 unveiled nine significant SNPs(four SNPs on chromosome 1 and five on chromosome 5)associated with oxalate content.These loci exhibited associations with six candidate genes,which might have potential contribution to oxalate content regulation.Remarkably,our GP models exhibited notable predictive abilities,yielding average accuracies of up to 0.51 for GEBV estimation.The integration of GWAS and GP approaches offers a holistic comprehension of the genetic underpinnings of oxalate content in spinach.These findings offered a promising avenue for the development of spinach cultivars and hybrids optimized for oxalate levels,promoting consumer health. 展开更多
关键词 GWAS Spinach breeding oxalate Genomic prediction
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The interfacial effect of SiO_(2)-Ni_(3)Mo_(3)N efficiently catalyzes the low-temperature hydrogenation of dimethyl oxalate to ethanol
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作者 Jiang Gong Fengling Zheng +6 位作者 Hanqing Zhang Weihan Shu Hao Wang Ni Zhang Pengbing Huang Chuancai Zhang Bin Dai 《Chinese Chemical Letters》 2025年第8期461-465,共5页
The hydrogenation of dimethyl oxalate(DMO)to ethanol(Et OH)represents a promising avenue for syngas conversion and plays a pivotal role in advancing sustainable energy economies.Nevertheless,designing catalysts with h... The hydrogenation of dimethyl oxalate(DMO)to ethanol(Et OH)represents a promising avenue for syngas conversion and plays a pivotal role in advancing sustainable energy economies.Nevertheless,designing catalysts with high Et OH yields at low temperatures remains a significant challenge.This study introduces an efficient catalyst featuring a rich SiO_(2)-Ni_(3)Mo_(3)N interface,which achieved a remarkable 97.5%Et OH yield at 210°C and 2 MPa.Impressively,an Et OH yield of 95%was also obtained at 210°C and 1.5 MPa.The research demonstrates that the addition of SiO_(2)fosters the development of a rich SiO_(2)-Ni_(3)Mo_(3)N interface,which enhances the concentration of Lewis acid sites(L-acid)and Brønsted acids sites(B-acid)within the catalyst.This enhancement promotes the adsorption of raw material and intermediate products while increasing H_(2)adsorption,thereby boosting the catalyst's deep hydrogenation capacity.Density functional theory(DFT)simulations indicate that SiO2incorporation modifies the catalyst's metal d-band center through electron transfer,increasing its adsorption capability for raw materials and intermediates and facilitating Et OH production.Consequently,this study achieves high Et OH yields at low temperatures,advances the industrialization process of syngas to Et OH conversion,and offers novel insights into constructing highly active catalytic interfaces for DMO hydrogenation. 展开更多
关键词 Dimethyl oxalate ETHANOL SiO_(2)-Ni_(3)Mo_(3)Ninterface Low temperature Acid sites d-band center
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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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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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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:12
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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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A collaborative strategy for enhanced reduction of Cr(Ⅵ) by Fe(0) in the presence of oxalate under sunlight:Performance and mechanism 被引量:4
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作者 Qi Zhou Yang Li +1 位作者 Heng Yang Yun Gao 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2020年第4期385-394,共10页
Nanometer-size zero-valent iron(NZVI)is an efficient reducing agent,but its surface is easily passivated with an oxide layer,leading to reaction inefficiency.In our study,oxalate(OA)was introduced into this heterogene... Nanometer-size zero-valent iron(NZVI)is an efficient reducing agent,but its surface is easily passivated with an oxide layer,leading to reaction inefficiency.In our study,oxalate(OA)was introduced into this heterogeneous system of NZVI,which could form ferrioxalate complexes with the NZVI surface-bound Fe3+and dissolved Fe3+in the solution.Photolysis of ferrioxalate complexes can facilitate the generation of Fe2+from Fe3+and CO2·-radical,both species have strong reduction capacity.Hence,a"photo-oxalate-Fe(0)"system through sunlight induction was established,which not only prohibited the formation of a surface passivation layer,but also displayed a synergetic mechanism of ferrioxalate photolysis to enhance reduction,exhibiting remarkably higher degradation activity(several times faster)toward the model pollutant Cr(Ⅵ)than the mechanism with NZVI alone.Factor tests suggested that both NZVI dosage and OA content markedly affected the reduction rate.Low pH was beneficial to the reduction efficiency.Moreover,recyclability experiment showed that the reduction rate decreased from 0.21706 to 0.03977 min-1 after three cycles of reuse due to the NZVI losing reaction activity generally,but the system still maintained considerable reduction capacity.Finally,a mechanism was revealed whereby NZVI would transform to Fe oxides after the exhaustion of its reductive power,and the photolysis of ferrioxalate to promote the cycling of iron species played the predominant role in providing extra reduction ability.These features confirm that introduction of OA into Cr(Ⅵ)reduction by NZVI through sunlight induction is advantageous and promising. 展开更多
关键词 Nanometer-size zero-valent iron oxalate Sun irradiation Photolysis of ferrioxalate Cycling of surface iron Synergetic mechanism
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Preparation of Diphenyl Oxalate from Transesterification of Dimethyl Oxalate with Phenol over TS-1 Catalyst 被引量:2
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作者 Xin Bin MA Sheng Ping WANG +1 位作者 Hong Li GUO Gen Hui XU 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第5期461-464,共4页
Diphenyl oxalate was synthesized from transesterification of dimethyl oxalate with phenol over TS-1 ( 2.5 wt% Ti ) catalyst. TS-1 catalyst, as a heterogeneous catalyst, showed excellent selectivity of diphenyl oxalat... Diphenyl oxalate was synthesized from transesterification of dimethyl oxalate with phenol over TS-1 ( 2.5 wt% Ti ) catalyst. TS-1 catalyst, as a heterogeneous catalyst, showed excellent selectivity of diphenyl oxalate and methylphenyl oxalate compared with other homogeneous catalysts. Lewis acid sites on TS-1 catalyst were the active sites for transesterification of dimethyl oxalate with phenol. The high selectivity was closely related to the weak acid sites over TS-1. 展开更多
关键词 Diphenyl oxalate TRANSESTERIFICATION dimethyl oxalate weak acid sites TS-1.
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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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Development of <i>α</i>-Amino Acid Detection with Peroxyoxalate Chemiluminescence by Using Water-Acetonitrile-Ethyl Acetate Mixed Solution
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作者 Hyo Kan Ryo Mizutani Kazuhiko Tsukagoshi 《American Journal of Analytical Chemistry》 2020年第1期15-24,共10页
Peroxyoxalate chemiluminescence was, for the first time, examined by using ternary mixed solutions of water-hydrophilic/hydrophobic organic solvent. Eosin Y as a model fluorescence compound was dissolved with the tern... Peroxyoxalate chemiluminescence was, for the first time, examined by using ternary mixed solutions of water-hydrophilic/hydrophobic organic solvent. Eosin Y as a model fluorescence compound was dissolved with the ternary solutions of water (1.0 mM carbonate buffer, pH 9.0)-acetonitrile-ethyl acetate, water-rich of 15:3:2 volume ratio and organic solvent-rich of 3:8:4 volume ratio, to which bis(2,4,6-trichlorophenyl) oxalate and hydrogen peroxide chemiluminescence reagent were added. The chemiluminescence observed with the ternary solutions, especially the organic solvent-rich solution, showed a larger signal than that observed with the water only solution or water-acetonitrile mixed solution. Chemiluminescence in the presence of twenty types of α-amino acid was similarly examined by using the ternary organic solvent-rich solution. The chemiluminescence of three α-amino acids with fluorescence properties was enhanced with the ternary solution. The data reported here may contribute to development of a new, sensitive peroxyoxalate chemiluminescence detection system. 展开更多
关键词 PEROXYoxalate chemiluminescence α-Amino Acids Water-Acetonitrile-Ethyl Acetate Bis(2 4 6-Trichlorophenyl) oxalate
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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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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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Electrical Investigation of Some Silver Containing Ceramics Obtained from Coprecipitated Oxalates 被引量:31
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作者 M.I.El-Hofy(Physics Department, Faculty of Science, Menoufia University, Shebin El-Kom, Egypt)A.M.Donia(Chemistry Department, Faculty of Science, Menoufia University, Shebin El-Kom, Egypt)M.M.Abou-Sekkina(Chemistry Department, Faculty of Science, Taota Un 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1999年第1期87-90,共4页
Silver-ceramics (Ag2MO2)(M=Co, Ni, or Cu) were prepared through thermal decompositionof coprecipitated oxalates. Pellets of these materials were annealed at 350℃ for different timeperiods up to 5 h. The effect of ann... Silver-ceramics (Ag2MO2)(M=Co, Ni, or Cu) were prepared through thermal decompositionof coprecipitated oxalates. Pellets of these materials were annealed at 350℃ for different timeperiods up to 5 h. The effect of annealing time on the transport properties was studied. IR andX-ray spectra were also studied. 展开更多
关键词 CuO Figure Electrical Investigation of Some Silver Containing Ceramics Obtained from Coprecipitated oxalates
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