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Adsorption of 2-naphthalenesulfonic acid/sulfuric acid/sulfurous acid from aqueous solution by iron-impregnated weakly basic resin:Equilibrium and model 被引量:1
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作者 Changhai Li Dongmei Jia 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第11期1522-1526,共5页
Commercial grade weakly basic resin D301 was impregnated with iron through a simple method using ferric chloride. Experiments for single, bisolute and trinary competitive adsorption were carried out to investigate the... Commercial grade weakly basic resin D301 was impregnated with iron through a simple method using ferric chloride. Experiments for single, bisolute and trinary competitive adsorption were carried out to investigate the adsorption behavior of 2-naphthalenesulfonic acid(NSA), sulfuric acid and sulfurous acid from their solution at 298 K onto the novel hybrid iron impregnated D301(Fe-D301). Adsorption affinity of NSA on Fe-D301 was found to be much higher than that of sulfuric acid, while adsorption affinity of sulfuric acid was slightly higher than that of sulfurous acid. The data of single-solute adsorption were fitted to the Langmuir model and the Freundlich adsorption model. The non-ideal competitive adsorbed model coupled with the single-solute adsorption models were used to predict the bisolute and trinary-solute competitive adsorption equilibria. The NICM coupled with the Langmuir model yields the favorable representation of the bisolute and trinary-solute competitive adsorption behavior. 展开更多
关键词 2-萘磺酸 弱碱性树脂 平衡模型 树脂吸附 亚硫酸 氯化铁 浸渍 水溶液
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Solubilities of 2-Naphthalenesulfonic Acid Monohydrate and Sodium 2-Naphthalenesulfonate in Sulfuric Acid Solution and Their Application for Preparing Sodium 2-Naphthalenesulfonate
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作者 张凤宝 景晖 +4 位作者 朱文宇 张林 刘博 张国亮 夏清 《Transactions of Tianjin University》 EI CAS 2016年第3期273-278,共6页
The solubilities of 2-naphthalenesulfonic acid monohydrate and sodium 2-naphthalenesulfonate in sulfuric acid solutions were measured at temperatures ranging from 278.15 to 338.15 K by using a dynamic method. The conc... The solubilities of 2-naphthalenesulfonic acid monohydrate and sodium 2-naphthalenesulfonate in sulfuric acid solutions were measured at temperatures ranging from 278.15 to 338.15 K by using a dynamic method. The concentration of sulfuric acid solution ranged from 0 to 80wt%,. The solubilities of 2-naphthalenesulfonic acid monohydrate and sodium 2-naphthalenesulfonate increased with temperature, and both of them were the lowest at 70wt %, of sulfuric acid solution(w^0_3 =0.70)while the highest in pure water. The solubility data were correlated by the modified Apelblat equation. Based on the solubility difference between 2-naphthalenesulfonic acid monohydrate and sodium 2-naphthalenesulfonate, a new technique in which sodium sulfate was used to replace sodium sulfite in the neutralization reaction was developed. The suitable mole ratio of H_2O to Na_2SO_4 in the neutralization reaction was 80∶1, and that of 2-naphthalenesulfonic acid monohydrate to Na_2SO_4 was 3.2∶1. The material balance under the suitable mole ratios was given and discussed. 展开更多
关键词 2-萘磺酸钠 溶解度数据 硫酸溶液 水合物 亚硫酸钠 应用 制备 温度范围
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Preparation of PrFe_(x)Co_(1-x)O_(3)/Mt catalyst and study on degradation of 2-hydroxybenzoic acid wastewater by catalytic wet peroxide oxidation
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作者 Binxia Zhao Yijia Gao +3 位作者 Tiancheng Hun Xiaoxiao Fan Nan Shao Xiaoqian Chen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期286-297,共12页
In this study,the perovskite nanocomposite PrFe_(x)Co_(1-x)O_(3)(Pr(S))was successfully synthesized by the sol-gel method;PrFe_(x)Co_(1-x)O_(3)/Al-pillared montmorillonite(Pr(S)/Mt)catalysts were prepared by impregnat... In this study,the perovskite nanocomposite PrFe_(x)Co_(1-x)O_(3)(Pr(S))was successfully synthesized by the sol-gel method;PrFe_(x)Co_(1-x)O_(3)/Al-pillared montmorillonite(Pr(S)/Mt)catalysts were prepared by impregnation(D)method and solid-melting(G)method,respectively,with Pr(S)as the active component and Al-pillared montmorillonite as the carrier.The catalysts were applied to treat the 2-hydroxybenzoic acid(2-HA)-simulated wastewater by catalytic wet peroxide oxidation(CWPO)technique,and the chemical oxygen demand(COD)removal rate and the 2-HA degradation rate were used as indicators to evaluate the catalytic performance.The results of the experiment indicated that the solid-melting method was more conducive to preparing the catalyst when the Co/Fe molar ratio of 7:3 and the optimal structural properties of the catalysts were achieved.The influence of operating parameters,including reaction temperature,catalyst dosage,H_(2)O_(2)dosage,pH,and initial 2-HA concentration,were optimized for the degradation of 2-HA by CWPO.The results showed that 97.64%of 2-HA degradation and 75.23%of COD removal rate were achieved under more suitable experimental conditions.In addition,after the catalyst was used five times,the degradation rate of 2-HA could still reach 76.93%,which implied the high stability and reusability of the catalyst.The high catalytic activity of the catalyst was due to the doping of Co into PrFeO_(3),which could promote the generation of HO·,and the high stability could be attributed to the loading of Pr(S)onto Al-Mt,which reduced the leaching of reactive metals.The study of reaction mechanism and kinetics showed that the whole degradation process conformed to the pseudo-firstorder kinetic equation,and the Langmuir-Hinshelwood method was applied to demonstrate that catalysis was dominant in the degradation process. 展开更多
关键词 MONTMORILLONITE PEROVSKITE Catalytic wet peroxide oxidation(CWPO) 2-Hydroxybenzoic acid
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Serum bile acid and unsaturated fatty acid profiles of non-alcoholic fatty liver disease in type 2 diabetic patients
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作者 Su-Su Feng Si-Jing Wang +8 位作者 Lin Guo Pan-Pan Ma Xiao-Long Ye Ming-Lin Pan Bo Hang Jian-Hua Mao Antoine M Snijders Yi-Bing Lu Da-Fa Ding 《World Journal of Diabetes》 SCIE 2024年第5期898-913,共16页
BACKGROUND The understanding of bile acid(BA)and unsaturated fatty acid(UFA)profiles,as well as their dysregulation,remains elusive in individuals with type 2 diabetes mellitus(T2DM)coexisting with non-alcoholic fatty... BACKGROUND The understanding of bile acid(BA)and unsaturated fatty acid(UFA)profiles,as well as their dysregulation,remains elusive in individuals with type 2 diabetes mellitus(T2DM)coexisting with non-alcoholic fatty liver disease(NAFLD).Investigating these metabolites could offer valuable insights into the pathophy-siology of NAFLD in T2DM.AIM To identify potential metabolite biomarkers capable of distinguishing between NAFLD and T2DM.METHODS A training model was developed involving 399 participants,comprising 113 healthy controls(HCs),134 individuals with T2DM without NAFLD,and 152 individuals with T2DM and NAFLD.External validation encompassed 172 participants.NAFLD patients were divided based on liver fibrosis scores.The analytical approach employed univariate testing,orthogonal partial least squares-discriminant analysis,logistic regression,receiver operating characteristic curve analysis,and decision curve analysis to pinpoint and assess the diagnostic value of serum biomarkers.RESULTS Compared to HCs,both T2DM and NAFLD groups exhibited diminished levels of specific BAs.In UFAs,particular acids exhibited a positive correlation with NAFLD risk in T2DM,while theω-6:ω-3 UFA ratio demonstrated a negative correlation.Levels ofα-linolenic acid andγ-linolenic acid were linked to significant liver fibrosis in NAFLD.The validation cohort substantiated the predictive efficacy of these biomarkers for assessing NAFLD risk in T2DM patients.CONCLUSION This study underscores the connection between altered BA and UFA profiles and the presence of NAFLD in individuals with T2DM,proposing their potential as biomarkers in the pathogenesis of NAFLD. 展开更多
关键词 Bile acid Non-alcoholic fatty liver disease Type 2 diabetes mellitus Unsaturated fatty acid
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Transforming liquid flow fuel cells to controllable reactors for highlyefficient oxidation of 5-hydroxymethylfurfural to 2, 5-furandicarboxylic acid at low temperature
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作者 Ye Qiang Xi Liu +2 位作者 Denghao Ouyang Zhao Jiang Xuebing Zhao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期621-631,I0014,共12页
Highly-efficient oxidation of 5-hydroxymethylfurtural(HMF) to 2,5-furandicarboxylic acid(FDCA) at low temperature with air as the oxidant is still challenging.Herein,inspired by the respirato ry electron transport cha... Highly-efficient oxidation of 5-hydroxymethylfurtural(HMF) to 2,5-furandicarboxylic acid(FDCA) at low temperature with air as the oxidant is still challenging.Herein,inspired by the respirato ry electron transport chain(ETC) of living cells mediated by electron carriers,we constructed artificial ETCs and transformed liquid flow fuel cells(LFFCs) to flexible reactors for efficient oxidation of HMF to produce FDCA under mild conditions.This LFFC reactor employed an electrodeposition modified nickel foam as an anode to promote HMF oxidation and(VO_(2))_(2)SO_(4) as a cathode electron carrier to facilitate the electron transfer to air.The reaction rate could be easily controlled by selecting the anode catalyst,adjusting the external loading and changing the cathodic electron carrier or oxidants.A maximal power density of 44.9 mW cm^(-2) at room temperature was achieved,while for FDCA production,short-circuit condition was preferred to achieve quick transfer of electrons.For a single batch operation with 0.1 M initial HMF,FDCA yield reached 97.1%.By fed-batch operation,FDCA concentration reached 144.5 g L^(-1) with a total yield of 96%.Ni^(2+)/Ni^(3+) redox couple was the active species mediating the electron transfer,while both experimental and DFT calculation results indicated that HMFCA pathway was the preferred reaction mechanism. 展开更多
关键词 5-HYDROXYMETHYLFURFURAL 2 5-Furandicarboxylic acid ELECTRODEPOSITION Electron transport chain Liquid flow fuel cell
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Enabling heterogeneous catalysis to achieve carbon neutrality: Directional catalytic conversion of CO_(2) into carboxylic acids
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作者 Xiaofei Zhang Wenhuan Huang +4 位作者 Le Yu Max García-Melchor Dingsheng Wang Linjie Zhi Huabin Zhang 《Carbon Energy》 SCIE EI CAS CSCD 2024年第3期1-35,共35页
The increase in anthropogenic carbon dioxide(CO_(2))emissions has exacerbated the deterioration of the global environment,which should be controlled to achieve carbon neutrality.Central to the core goal of achieving c... The increase in anthropogenic carbon dioxide(CO_(2))emissions has exacerbated the deterioration of the global environment,which should be controlled to achieve carbon neutrality.Central to the core goal of achieving carbon neutrality is the utilization of CO_(2) under economic and sustainable conditions.Recently,the strong need for carbon neutrality has led to a proliferation of studies on the direct conversion of CO_(2) into carboxylic acids,which can effectively alleviate CO_(2) emissions and create high-value chemicals.The purpose of this review is to present the application prospects of carboxylic acids and the basic principles of CO_(2) conversion into carboxylic acids through photo-,electric-,and thermal catalysis.Special attention is focused on the regulation strategy of the activity of abundant catalysts at the molecular level,inspiring the preparation of high-performance catalysts.In addition,theoretical calculations,advanced technologies,and numerous typical examples are introduced to elaborate on the corresponding process and influencing factors of catalytic activity.Finally,challenges and prospects are provided for the future development of this field.It is hoped that this review will contribute to a deeper understanding of the conversion of CO_(2) into carboxylic acids and inspire more innovative breakthroughs. 展开更多
关键词 carbon neutrality carboxylic acids CO_(2)conversion heterogeneous catalyst in situ technology
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Landscape of Sequence Variations in Homologous Copies of FAD2 and FAD3 in Rapeseed(Brassica napus L.)Germplasm with High/Low Linolenic Acid Trait
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作者 Haoxue Wu Xiaohan Zhang +5 位作者 Xiaoyu Chen Kang Li Aixia Xu Zhen Huang Jungang Dong Chengyu Yu 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第3期627-640,共14页
Genetic manipulation(either restraint or enhancement)of the biosynthesis pathway ofα-linolenic acid(ALA)in seed oil is an important goal in Brassica napus breeding.B.napus is a tetraploid plant whose genome often har... Genetic manipulation(either restraint or enhancement)of the biosynthesis pathway ofα-linolenic acid(ALA)in seed oil is an important goal in Brassica napus breeding.B.napus is a tetraploid plant whose genome often har-bors four and six homologous copies,respectively,of the two fatty acid desaturases FAD2 and FAD3,which con-trol the last two steps of ALA biosynthesis during seed oil accumulation.In this study,we compared their promoters,coding sequences,and expression levels in three high-ALA inbred lines 2006L,R8Q10,and YH25005,a low-ALA line A28,a low-ALA/high-oleic-acid accession SW,and the wildtype ZS11.The expression levels of most FAD2 and FAD3 homologs in the three high-ALA accessions were higher than those in ZS11 and much higher than those in A28 and SW.The three high-ALA accessions shared similar sequences with the pro-moters and CDSs of BnFAD3.C4 and BnFAD3.A3.In A28 and SW,substitution of three amino acid residues in BnFAD2.A5 and BnFAD2.C5,an absence of BnFAD2.C1 locus,and a 549 bp long deletion on the BnFAD3.A3 promoter were detected.The profile of BnFAD2 mutation in the two low-ALA accessions A28 and SW is different from that reported in previous studies.The mutations in BnFAD3 in the high-ALA accessions are reported for thefirst time.In identifying the sites of these mutations,we provide detailed information to aid the design of mole-cular markers for accelerated breeding schemes. 展开更多
关键词 Brassica napus linolenic acid FAD2 FAD3 promoter coding sequences mutation
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Betulinic acid protects against ovarian impairment by decreasing F-2 toxin-induced oxidative stress and inflammation associated with the downregulation of p38 expression in mice
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作者 Li Kong Xinyu Gao +9 位作者 Lijuan Zhu Xing Lin You Huang Chunlin Huang Wenjiang Yang Yazhi Chen Haoqiang Zhao Jing Wu Zhihang Yuan Jin’e Yi 《Food Science and Human Wellness》 SCIE CSCD 2024年第3期1292-1302,共11页
F-2 toxin is an estrogenic mycotoxin that causes reproductive disorders in animals.Betulinic acid(BA)is a natural pentacyclic lupane-structure triterpenoid that has diverse pharmacological activities.In this study,the... F-2 toxin is an estrogenic mycotoxin that causes reproductive disorders in animals.Betulinic acid(BA)is a natural pentacyclic lupane-structure triterpenoid that has diverse pharmacological activities.In this study,the antioxidative and anti-inflammatory effects of BA and its underlying mechanism are explored in F-2 toxin-triggered mouse ovarian damage.We found that BA alleviated the F-2 toxin-induced ovarian impairment by stimulating follicle growth,reducing inflammatory cell infiltration,repairing damaged mitochondria and endoplasmic reticulum.Simultaneously,BA not only reversed F-2 toxin-induced reduction of follicle stimulating hormone(FSH)and luteinizing hormone(LH)levels in the serum,but also restrained the protein expression of the estrogen receptors a(ERa)and ERβ.Moreover,BA restored the balance of F-2 toxin-induced ovarian redox system disorders.Subsequently,we found that 0.25 mg/kg BA played an anti-inflammatory role in the F-2 toxin-induced ovarian impairment by decreasing interleukin-1β(IL-1β).IL-6,and tumor necrosis factor-α(TNF-α)mRNA expression,as well as inhibiting p38 protein expression.These data demonstrated that BA exerts its protective effect on F-2 toxin-induced ovarian oxidative impairment and inflammation by inhibiting p38 expression,which implies a natural product-based medicine to ameliorate F-2 toxin-caused female reproductive toxicity and provides a detoxifying method for food contaminated by mycotoxin. 展开更多
关键词 Betulinic acid F-2 toxin Ovarian damage p38 MAPK signaling pathway
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2-O-β-D-Glucopyranosyl-L-ascorbic acid,an ascorbic acid derivative isolated from the fruits of Lycium barbarum L.,ameliorates high fructose-induced neuroinflammation in mice:involvement of gut microbiota and leaky gut
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作者 Wei Dong Yujia Peng +9 位作者 Guijie Chen Zhiyong Xie Weiqi Xu Wangting Zhou Jia Mi Lu Lu Yi Sun Xiaoxiong Zeng Youlong Cao Yamei Yan 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期241-253,共13页
Western diet(rich in highly refined sugar and fat)can induce a range of metabolic dysfunctions in animals and humans,including neuroinflammation and cognitive function decline.Neuroinflammation and cognitive impairmen... Western diet(rich in highly refined sugar and fat)can induce a range of metabolic dysfunctions in animals and humans,including neuroinflammation and cognitive function decline.Neuroinflammation and cognitive impairment,two critical pathological characteristics of Alzheimer’s disease,have been closely associated with microbial alteration via the gut-brain axis.Thus,the present study aimed to investigate the influence of 2-O-β-D-glucopyranosyl-L-ascorbic acid(AA-2βG)isolated from the fruits of Lycium barbarum on preventing the high-fructose diet(HFrD)induced neuroinflammation in mice.It was found that AA-2βG prevented HFr D-induced cognitive deficits.AA-2βG also predominantly enhanced the gut barrier integrity,decreased lipopolysaccharide entry into the circulation,which subsequently countered the activation of glial cells and neuroinflammatory response.These beneficial effects were transmissible by horizontal fecal microbiome transplantation,transferring from AA-2βG fed mice to HFr D fed mice.Additionally,AA-2βG exerted neuroprotective effects involving the enrichment of Lactobacillus and Akkermansia,potentially beneficial intestinal bacteria.The present study provided the evidence that AA-2βG could improve indices of cognition and neuroinflammmation via modulating gut dybiosis and preventing leaky gut.As a potential functional food ingredient,AA-2βG may be applied to attenuate neuroinflammation associated with Western-style diets. 展开更多
关键词 Neuroinfl ammation Gut microbiota Leaky gut Lipopolysaccharide Fecal microbiome transplantation 2-O-β-D-Glucopyranosyl-L-ascorbic acid
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Heterogeneously elevated branched-chain/aromatic amino acids among new-onset type-2 diabetes mellitus patients are potentially skewed diabetes predictors
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作者 Min Wang Yang Ou +7 位作者 Xiang-Lian Yuan Xiu-Fang Zhu Ben Niu Zhuang Kang Bing Zhang Anwar Ahmed Guo-Qiang Xing Heng Su 《World Journal of Diabetes》 SCIE 2024年第1期53-71,共19页
BACKGROUND The lack of specific predictors for type-2 diabetes mellitus(T2DM)severely impacts early intervention/prevention efforts.Elevated branched-chain amino acids(BCAAs:Isoleucine,leucine,valine)and aromatic amin... BACKGROUND The lack of specific predictors for type-2 diabetes mellitus(T2DM)severely impacts early intervention/prevention efforts.Elevated branched-chain amino acids(BCAAs:Isoleucine,leucine,valine)and aromatic amino acids(AAAs:Tyrosine,tryptophan,phenylalanine)show high sensitivity and specificity in predicting diabetes in animals and predict T2DM 10-19 years before T2DM onset in clinical studies.However,improvement is needed to support its clinical utility.AIM To evaluate the effects of body mass index(BMI)and sex on BCAAs/AAAs in new-onset T2DM individuals with varying body weight.METHODS Ninety-seven new-onset T2DM patients(<12 mo)differing in BMI[normal weight(NW),n=33,BMI=22.23±1.60;overweight,n=42,BMI=25.9±1.07;obesity(OB),n=22,BMI=31.23±2.31]from the First People’s Hospital of Yunnan Province,Kunming,China,were studied.One-way and 2-way ANOVAs were conducted to determine the effects of BMI and sex on BCAAs/AAAs.RESULTS Fasting serum AAAs,BCAAs,glutamate,and alanine were greater and high-density lipoprotein(HDL)was lower(P<0.05,each)in OB-T2DM patients than in NW-T2DM patients,especially in male OB-T2DM patients.Arginine,histidine,leucine,methionine,and lysine were greater in male patients than in female patients.Moreover,histidine,alanine,glutamate,lysine,valine,methionine,leucine,isoleucine,tyrosine,phenylalanine,and tryptophan were significantly correlated with abdominal adiposity,body weight and BMI,whereas isoleucine,leucine and phenylalanine were negatively correlated with HDL.CONCLUSION Heterogeneously elevated amino acids,especially BCAAs/AAAs,across new-onset T2DM patients in differing BMI categories revealed a potentially skewed prediction of T2DM development.The higher BCAA/AAA levels in obese T2DM patients would support T2DM prediction in obese individuals,whereas the lower levels of BCAAs/AAAs in NW-T2DM individuals may underestimate T2DM risk in NW individuals.This potentially skewed T2DM prediction should be considered when BCAAs/AAAs are to be used as the T2DM predictor. 展开更多
关键词 Hyperaminoacidemia Branched-chain/aromatic amino acids New-onset type-2 diabetes Predictor Obesity SEX
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基于2-硫代巴比妥酸构筑零维原子簇{[Cu_(6)(H_(2)tba)_(6)]·2DMF·xSolvent}、二维层状{[Sc(H_(2)tba)_(3)(DMF)]·2DMF}_(n)和三维网状{[Fe(H_(2)tba)_(2)(H_(2)O)_(2)]·2DMF}_(n)
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作者 王超 何东美 +5 位作者 管裕 许嘉怡 郑利民 林悦健 陈珍霞 梁凯 《无机化学学报》 SCIE CSCD 北大核心 2024年第1期263-269,共7页
分别以Cu(ClO_(4))_(2)·6H_(2)O、Sc(ClO_(4))_(3)·6H_(2)O和Fe(ClO_(4))_(3)·9H_(2)O为金属盐,2-硫代巴比妥酸(H_(3)tba)为配体,通过扩散反应得到了3种不同结构的配合物{[Cu_(6)(H_(2)tba)_(6)]·2DMF·xSolven... 分别以Cu(ClO_(4))_(2)·6H_(2)O、Sc(ClO_(4))_(3)·6H_(2)O和Fe(ClO_(4))_(3)·9H_(2)O为金属盐,2-硫代巴比妥酸(H_(3)tba)为配体,通过扩散反应得到了3种不同结构的配合物{[Cu_(6)(H_(2)tba)_(6)]·2DMF·xSolvent}(1)、{[Sc(H_(2)tba)_(3)(DMF)]·2DMF}_(n)(2)和[Fe(H_(2)tba)_(2)(H_(2)O)_(2)]_(n)(3),并用红外光谱、元素分析、热重分析和粉末X射线衍射对配合物进行了表征。单晶X射线衍射结构分析表明配合物1是一个具有三方反棱柱构型的六核铜原子簇合物,配合物2是一个具有二维层状结构的化合物,配合物3是一个具有三维网状结构的配位聚合物。配合物1在390 nm光照激发下在735 nm处有强的荧光发射峰。 展开更多
关键词 2-硫代巴比妥酸 配位聚合物 荧光性质
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富里酸和Ca^(2+)共存对嗜酸性氧化亚铁硫杆菌介导生成次生高铁矿物的影响
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作者 黄海涛 王崇 +2 位作者 耿康慧 魏彩春 靳振江 《环境污染与防治》 CAS CSCD 北大核心 2024年第2期169-173,180,共6页
为揭示富里酸和Ca^(2+)共存对嗜酸性氧化亚铁硫杆菌(Acidithiobacillus ferrooxidans)氧化酸性矿山废水(AMD)中的Fe^(2+)和形成次生高铁矿物的影响,分析了pH、Fe^(2+)氧化率、铁沉淀率以及次生高铁矿物矿相、基团等相关指标。结果表明,C... 为揭示富里酸和Ca^(2+)共存对嗜酸性氧化亚铁硫杆菌(Acidithiobacillus ferrooxidans)氧化酸性矿山废水(AMD)中的Fe^(2+)和形成次生高铁矿物的影响,分析了pH、Fe^(2+)氧化率、铁沉淀率以及次生高铁矿物矿相、基团等相关指标。结果表明,Ca^(2+)确实具有提高嗜酸性氧化亚铁硫杆菌氧化Fe^(2+)的能力。低质量浓度(0.2 g/L)的富里酸对嗜酸性氧化亚铁硫杆菌活性的提高具有促进作用,高质量浓度(0.4 g/L)的富里酸具有抑制作用,而增加Ca^(2+)反过来能够减弱高浓度富里酸对嗜酸性氧化亚铁硫杆菌的抑制作用。对形成的次生高铁矿物进行X射线衍射(XRD)和傅立叶红外光谱(FTIR)分析,结果表明高浓度富里酸促进了另一次生高铁矿物草黄铁矾的生成。 展开更多
关键词 酸性矿山废水 嗜酸性氧化亚铁硫杆菌 富里酸 CA^(2+) 次生高铁矿物
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Ni/ZrO_(2)-SO_(4)^(2-)催化剂的制备及其催化甲烷与CO_(2)制乙酸性能
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作者 任行涛 吴俊 +3 位作者 贾志光 丁靖 万辉 管国锋 《石油化工》 CAS CSCD 北大核心 2024年第4期489-495,共7页
以Zr(NO_(3))4·5H_(2)O和Ni(NO_(3))2·6H_(2)O为原料、(NH4)2CO_(3)为沉淀剂,采用溶胶凝胶-硫酸酸化两步法制备了Ni/ZrO_(2)-SO_(4)^(2-)催化剂,采用XRD,FTIR,SEM,N_(2)吸附-脱附,H_(2)-TPR,NH3-TPD等方法对Ni/ZrO_(2)-SO_(4)... 以Zr(NO_(3))4·5H_(2)O和Ni(NO_(3))2·6H_(2)O为原料、(NH4)2CO_(3)为沉淀剂,采用溶胶凝胶-硫酸酸化两步法制备了Ni/ZrO_(2)-SO_(4)^(2-)催化剂,采用XRD,FTIR,SEM,N_(2)吸附-脱附,H_(2)-TPR,NH3-TPD等方法对Ni/ZrO_(2)-SO_(4)^(2-)催化剂进行表征,考察了Ni的引入方式对催化剂的结构和性能的影响。实验结果表明,与共沉淀方式引入Ni制备的Ni/ZrO_(2)-SO_(4)^(2-)催化剂相比,采用溶胶凝胶方式引入Ni制备的催化剂的四方相ZrO_(2)占比更高,表面酸量更多,且具有良好的热稳定性和较强的L酸性;采用溶胶凝胶方式引入Ni制备的Ni/ZrO_(2)-SO_(4)^(2-)催化剂的乙酸生成量明显优于共沉淀方式引入Ni制备的Ni/ZrO_(2)-SO_(4)^(2-)催化剂。四方相ZrO_(2)、酸性位点和过渡金属Ni之间的协同作用促进了甲烷与CO_(2)直接反应合成乙酸。 展开更多
关键词 Ni/ZrO_(2)-SO_(4)^(2-) 溶胶-凝胶法 甲烷 乙酸 合成
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Cu(110)晶面催化还原CO_(2)制备甲酸机理的第一性原理研究
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作者 张旭昀 汤静 +2 位作者 常庆 王勇 谭秀娟 《功能材料》 CAS CSCD 北大核心 2024年第4期4102-4110,共9页
铜基催化剂是一种高效还原CO_(2)为甲酸的绿色催化剂,明确不同晶面的还原机理对催化剂的设计及开发具有重要指导意义,但Cu(110)晶面的催化机理尚不明确。采用基于密度泛函理论的第一性原理方法对Cu(110)表面的还原机理进行了研究,系统... 铜基催化剂是一种高效还原CO_(2)为甲酸的绿色催化剂,明确不同晶面的还原机理对催化剂的设计及开发具有重要指导意义,但Cu(110)晶面的催化机理尚不明确。采用基于密度泛函理论的第一性原理方法对Cu(110)表面的还原机理进行了研究,系统研究了不同中间产物的吸附相关性质并探讨了相关的吸附机理。吸附能结果表明,CO_(2)在Cu(110)表面无法发生化学吸附,而^(*)COOH、^(*)HCOO、HCOOH分子和H原子的最稳定吸附位点分别为长桥位点、短桥位点、顶位点和HCP位点。布居数结果表明,^(*)HCOO和HCOOH分子在吸附过程中与Cu(110)表面的Cu原子形成离子键,H原子和Cu原子之间存在氢键作用,^(*)COOH分子中的C和Cu原子形成共价键。此外,电子态密度结果表明^(*)HCOO基团和Cu原子之间形成O—Cu键,^(*)COOH基团中的C和Cu原子形成C—Cu键,HCOOH分子中的O和Cu原子形成O—Cu键。相比于^(*)COOH/Cu(110)体系,^(*)HCOO/Cu(110)吸附体系的电荷密度、电荷转移量和成键能力均较强,说明CO_(2)在Cu(110)还原过程中中间体^(*)HCOO更稳定,合成路径属于更加高效的:CO_(2)→^(*)HCOO→HCOOH路径。 展开更多
关键词 电催化 二氧化碳还原 甲酸 第一性原理 铜基催化剂
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超临界CO_(2)对致密碳酸盐岩力学特性影响
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作者 苟波 王琨 +2 位作者 李骁 詹立 刘超 《西南石油大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第2期65-76,共12页
采用超临界CO_(2)破致密碳酸盐岩具有破裂压力低,易形成复杂缝特点,但其作用的力学机理尚未清晰。选用马家沟组致密白云岩样,采用高温高压超临界CO_(2)饱和流体法,研究了岩样在超临界CO_(2)+地层水的流体中浸泡不同时间后的物性、声波... 采用超临界CO_(2)破致密碳酸盐岩具有破裂压力低,易形成复杂缝特点,但其作用的力学机理尚未清晰。选用马家沟组致密白云岩样,采用高温高压超临界CO_(2)饱和流体法,研究了岩样在超临界CO_(2)+地层水的流体中浸泡不同时间后的物性、声波响应、岩石力学特性和破裂形态特征。结果表明,随着浸泡时间增加,化学溶蚀作用引起溶蚀孔径增大,岩样孔隙度、渗透率增加,而声波速度、动态和静态岩石力学参数均下降;当浸泡时间大于1.0 d后,岩样物性参数增大和力学强度降低明显;随着浸泡时间增加,岩样破裂形态由单一低角度剪切缝向高角度剪切缝、共轭缝和剪切、张型复合缝等复杂形态发展;压裂短时间内(小于1.0 d)超临界CO_(2)+地层水形成的弱酸对岩石力学强度劣化程度有限。 展开更多
关键词 致密碳酸盐岩 超临界CO_(2) 前置酸压 力学强度 破裂形态
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2型糖尿病合并冠心病患者血清Hcy、HbAlc和血尿酸水平变化的临床意义
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作者 李玲 晏益民 +2 位作者 廖世波 向成 肖潇 《北华大学学报(自然科学版)》 CAS 2024年第1期76-81,共6页
目的探讨2型糖尿病合并冠心病患者血清同型半胱氨酸(Hcy)、糖化血红蛋白(HbAlc)和血尿酸水平变化的临床意义。方法选取2型糖尿病合并冠心病患者60例为合并冠心病组,单纯2型糖尿病患者45例为单纯糖尿病组,健康志愿者30名为健康对照组。... 目的探讨2型糖尿病合并冠心病患者血清同型半胱氨酸(Hcy)、糖化血红蛋白(HbAlc)和血尿酸水平变化的临床意义。方法选取2型糖尿病合并冠心病患者60例为合并冠心病组,单纯2型糖尿病患者45例为单纯糖尿病组,健康志愿者30名为健康对照组。采集空腹外周静脉血,检测血清Hcy、HbAlc及血尿酸水平;行冠状动脉造影检查,记录冠脉狭窄程度50%及以上的病变累及左前降支、回旋支或右冠脉的支数(单支病变、双支病变、多支病变)。收集2型糖尿病合并冠心病患者的年龄、性别、身高、体质量、吸烟情况及低密度脂蛋白、总胆固醇、甘油三酯、空腹血糖、维生素B12、叶酸水平。进行3 a随访,记录患者病情加重再入院、死亡情况。结果合并冠心病组血清Hcy、HbAlc及血尿酸水平明显高于单纯糖尿病组和健康对照组(P<0.05);多支病变患者血清Hcy、HbAlc及血尿酸水平明显高于双支病变和单支病变患者(P<0.05);预后不良组患者血清Hcy、HbAlc及血尿酸水平明显高于预后良好组患者(P<0.05);预后不良组患者中吸烟比例、空腹血糖水平明显高于预后良好组(P<0.05)。Hcy、HbAlc、血尿酸是2型糖尿病合并冠心病患者预后的独立影响因素。ROC曲线分析显示,血清Hcy、HbAlc及血尿酸水平对2型糖尿病合并冠心病患者预后具有较高的预测价值(P<0.05),联合检测的预测价值最高(AUC=0.947)。结论2型糖尿病合并冠心病患者血清Hcy、HbAlc及血尿酸水平升高,且与冠脉病变程度密切相关,联合检测可用于患者预后评估。 展开更多
关键词 2型糖尿病 冠心病 同型半胱氨酸 糖化血红蛋白 血尿酸 预后
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新标09CrCuSb耐酸钢的耐50%H_(2)SO_(4)腐蚀性能
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作者 郑健 张佳伟 +3 位作者 袁渊 张成元 黄峰 刘静 《腐蚀与防护》 CAS CSCD 北大核心 2024年第4期8-13,共6页
通过电化学测试和全浸腐蚀试验,研究了不同温度(25,50,60,70℃)条件下新标09CrCuSb耐酸钢在50%H_(2)SO_(4)溶液中的腐蚀行为。结果表明:随着温度从25℃升至70℃,新标09CrCuSb钢的腐蚀速率整体呈现增大趋势,在70℃时,腐蚀速率达到最高,为... 通过电化学测试和全浸腐蚀试验,研究了不同温度(25,50,60,70℃)条件下新标09CrCuSb耐酸钢在50%H_(2)SO_(4)溶液中的腐蚀行为。结果表明:随着温度从25℃升至70℃,新标09CrCuSb钢的腐蚀速率整体呈现增大趋势,在70℃时,腐蚀速率达到最高,为2.70 g/(m^(2)·h),这与随温度升高,腐蚀产物中具有保护性作用的Fe_(3)O_(4)含量减少,无保护作用的FeSO_(4)·H_(2)O含量增加以及锈层中微孔变化有关。另外,由于新标调整了09CrCuSb钢中Cu、Mo、Sn、Sb、W等元素的含量,与旧标09CrCuSb钢相比,阳极维钝电流密度J维钝降低,同等温度条件下,新标09CrCuSb钢的耐蚀性得到较大改善。 展开更多
关键词 新标09CrCuSb耐酸钢 50%H_(2)SO_(4)溶液 腐蚀 温度影响
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2%超分子水杨酸对UVB所致小鼠光老化损伤的修复研究
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作者 孙晓娟 杜晓婕 +2 位作者 周红梅 王瞾 曾维惠 《中国实用医药》 2024年第8期177-180,共4页
目的 探究2%超分子水杨酸对中波紫外线(UVB)所致小鼠光老化损伤的修复作用。方法 选择30只6~8周龄昆明雌鼠,随机分为空白对照组、UVB组、UVB+2%超分子水杨酸组,各10只。空白对照组小鼠正常日光照射饲养, UVB组、UVB+2%超分子水杨酸组隔... 目的 探究2%超分子水杨酸对中波紫外线(UVB)所致小鼠光老化损伤的修复作用。方法 选择30只6~8周龄昆明雌鼠,随机分为空白对照组、UVB组、UVB+2%超分子水杨酸组,各10只。空白对照组小鼠正常日光照射饲养, UVB组、UVB+2%超分子水杨酸组隔日用UVB照射1次,辐照12周,其中UVB+2%超分子水杨酸组小鼠在UVB照射后涂抹1次2%超分子水杨酸,非照射日每日涂抹1次;最后1次辐照结束后48 h观察三组小鼠皮肤组织形态变化情况,应用苏木精-伊红(HE)染色观察小鼠背部皮肤显微结构改变情况,测定表皮、真皮厚度,应用Masson染色观察真皮胶原纤维排列情况,测定胶原纤维含量,用免疫组化染色观察皮肤组织p21、p53表达情况。比较三组小鼠背部皮肤外形情况、皮肤显微结构改变情况及皮肤组织p21、p53阳性表达情况。结果 与空白对照组相比,UVB组小鼠皮肤粗糙,有深皱纹毛孔扩大,缺乏弹性,皮肤呈褐黄色斑,皮革样外观,镜下见毛细血管扩张,结痂,为典型光老化特征;UVB+2%超分子水杨酸组皮肤外观有隐约褐色斑,镜下见皮肤有散在、不规则褐色斑片,光老化症状较轻。三组背部皮肤损伤程度比较有明显差异性(P<0.05);UVB组背部皮肤损伤程度明显大于空白对照组和UVB+2%超分子水杨酸组,有明显差异性(P<0.05);空白对照组与UVB+2%超分子水杨酸组皮损程度比较也有明显差异性(P<0.05)。空白对照组表皮厚度、真皮厚度、真皮胶原纤维含量分别为(18.55±1.80)μm、(350.08±35.16)μm、(0.46±0.05)OD, UVB组分别为(79.68±21.37)μm、(611.62±16.37)μm、(0.15±0.30)OD, UVB+2%超分子水杨酸组分别为(60.99±11.49)μm、(467.94±20.71)μm、(0.32±0.03)OD。三组表皮厚度、真皮厚度及真皮胶原纤维含量比较有明显差异性(P<0.05);UVB+2%超分子水杨酸组和UVB组表皮厚度、真皮厚度明显多于空白对照组,真皮胶原纤维含量显著少于空白对照组,有明显差异性(P<0.05);UVB+2%超分子水杨酸组表皮厚度、真皮厚度明显少于UVB组,真皮胶原纤维含量多于UVB组,有明显差异性(P<0.05)。免疫组化显示空白对照组未见有p21、p53阳性表达。UVB+2%超分子水杨酸组皮肤组织p21、p53阳性表达率分别为30.00%、10.00%,低于UVB组的80.00%、60.00%,有明显差异性(P<0.05)。结论 2%超分子水杨酸对UVB所致小鼠光老化皮肤有修护保护作用,其机制与抑制凋亡相关基因p21、p53表达有关。 展开更多
关键词 皮肤光老化 2%超分子水杨酸 中波紫外线
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支链氨基酸代谢与2型糖尿病关系的研究进展
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作者 张帆 杨宇峰 《中国医药科学》 2024年第8期41-44,共4页
支链氨基酸(BCAAs)是一类因存在脂肪烃链而得名的必需氨基酸,包括亮氨酸、异亮氨酸以及缬氨酸。BCAAs同胰岛素抵抗的关系于1964年被提出,该类氨基酸在膳食中常见,其循环水平通过对糖脂代谢和胰岛素分泌的调控对2型糖尿病(T2DM)病程发展... 支链氨基酸(BCAAs)是一类因存在脂肪烃链而得名的必需氨基酸,包括亮氨酸、异亮氨酸以及缬氨酸。BCAAs同胰岛素抵抗的关系于1964年被提出,该类氨基酸在膳食中常见,其循环水平通过对糖脂代谢和胰岛素分泌的调控对2型糖尿病(T2DM)病程发展起着重要的作用。作为一种发病率高、并发症严重的慢性代谢性疾病,糖尿病已经对全球人民生活生产造成了极大的困扰。其中T2DM作为糖尿病中占比最高的类型,正大幅度降低患者的生活质量。本文通过糖脂代谢以及其他相关机制,将BCAAs代谢分解过程与T2DM发生发展联系起来,从而为临床T2DM的治疗诊断提供更多思路。 展开更多
关键词 支链氨基酸 支链酮酸 2型糖尿病 糖尿病
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LuxS/AI-2群体感应系统在乳酸菌细菌素合成中的作用
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作者 满丽莉 向殿军 《中国调味品》 CAS 北大核心 2024年第3期214-220,共7页
乳酸菌细菌素具有抑菌谱广、稳定性高、安全性高等优势,作为新型生物防腐剂备受青睐,但目前工业化应用的细菌素数量有限,合成量低是其应用受限的重要原因。国内外研究显示与特定的微生物共培养是提高乳酸菌细菌素合成量的有效方法,该过... 乳酸菌细菌素具有抑菌谱广、稳定性高、安全性高等优势,作为新型生物防腐剂备受青睐,但目前工业化应用的细菌素数量有限,合成量低是其应用受限的重要原因。国内外研究显示与特定的微生物共培养是提高乳酸菌细菌素合成量的有效方法,该过程受到LuxS/AI-2群体感应系统的调控。文章从乳酸菌LuxS/AI-2群体感应系统的组成及LuxS/AI-2群体感应系统在乳酸菌细菌素合成中的作用两个方面进行论述,为乳酸菌细菌素合成量的提高和工业化应用的实现提供了一定的理论依据。 展开更多
关键词 LuxS/AI-2群体感应系统 乳酸菌 细菌素 合成
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