Oxide ion diffusion in Ba-doped LaInO3 perovskite A molecular dynamics study

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稀土水杨酸邻菲罗啉三元固体配合物的研究

稀土水杨酸邻菲罗啉三元固体配合物的研究近年来，稀土水杨酸邻菲罗啉三元固体配合物(REY-LFL)作为新型有机半导体材料，表现出非常优异的物理和化学性质，具有广阔的应用前景，因此，开展其研究就变得尤为重要。

本文将系统回顾有关REY-LFL固体组合物的研究，主要包括结构、光谱、机械性质和电学性质等方面的研究，并着重介绍在REY-LFL固体组合物中，稀土元素的作用及其有趣的性质。

二、结构REY-LFL组合物是由稀土部分（REY）以及氨基酸部分（LFL）构成的高分子复合物，稀土部分是由稀土元素(REY=Rare Earth)组成的，包括铕、钇、铽、钆、、钪、铼、铯等；氨基酸部分是由邻菲罗啉酸（LFL=Lanthanide Fluorolactate）组成的。

究表明，REY-LFL组合物的晶体结构具有半金属半介电的衍生物共价键网络，REY i +LFL j REY i + LFL j 。

这种网络能够坚固地立体结合，具有很强的热稳定性，且不受磁场影响。

在REY-LFL组合物中，稀土元素包裹在稳定的氨基酸环境中，其结构稳定性增强，具有更好的特性。

三、光谱REY-LFL组合物具有多种不同的光谱行为。

其中包括紫外-可见-近红外吸收光谱，X射线衍射（XRD），核磁共振（NMR），热重分析（TGA）等。

紫外-可见-近红外（UV-vis-NIR）吸收光谱表明，REY-LFL组合物具有很高的光学窗口，可以将紫外、可见、近红外光谱统一在一起，可用来测量材料的光性能和机械性能，从而对稀土水杨酸邻菲罗啉三元固体组合物的性质有进一步的了解。

X射线衍射（XRD）是一种用于表征晶体结构及确定晶体结构参数的常用技术，可以准确地检测REY-LFL组合物的晶体结构和结构参数，快速了解它们的结构性质。

根据XRD的研究，发现REY-LFL组合物中的稀土元素（REY）和氨基酸（LFL）能够形成很强的共价键，形成强固的网络结构，且结构可以很好地调节组合物的电学性质。

pH值对溶胶凝胶-燃烧合成纳米晶LaMnO_3粉末的影响

热重／差热分析仪，ｌ￣／ｎ的加热速度下，析干在ＯＣｍｉ分凝胶热分解过程；采用荷兰Ｘ’ ｅｔＲ型Ｘ射线衍射ＰｒＰＯ
仪分析干凝胶及合成粉体进行ｘ射线衍射分析（ Ⅺ ），
用Ｃ靶Ｋａｕ线辐射，管电流１００ｍＡ，电压５ｋ扫描管ＯＶ，速度为４／ｉ，￣ｍｎ扫描角度２￣７。并用Ｓｈｒｒ００，ｃｅｒ公式计ｅ
的烧杯分别置于９￣０Ｃ的水浴电磁搅拌器中加热以形成凝胶（子转速２ｒｓ，转０／）将所得到的溶胶在真空干燥箱
关键词：溶胶凝胶一烧合成；米晶；ａＯ；Ｈ值燃纳ＬＭｎ３ｐ中图分类号：Ｔ０８Ｑ３文章编号：０１９３（０００ —１１０１０ —７１２１）１０２—３文献标识码：Ａ
法中成分原子水平均匀混合的优势，保留了自蔓延高又
团的变化；用铂金一尔默仪器（海）限公司采埃上有
（ｅｋｎｌｒｎｔｍｅｔ）产的ＤａｎＧＤＡ型ＰｒｉＥｍｅｓｕｎｓ生ＩｒｉｍｏｄＴ／Ｔ
李元元等：Ｈ值对溶胶凝胶一烧合成纳米晶ＬＭｎ３粉末的影响ｐ燃ａＯ
ｐ值对溶胶凝胶一Ｈ燃烧合成纳米晶ＬＭｎ３末的影响ａＯ粉
李元元，薛丽红，严有为
（中科技大学模具技术国家重点实验室，北武汉４０７）华湖３０４

LaCoO3钙钛矿型催化剂非均相Fenton处理兰炭废水

LaCoO3钙钛矿型催化剂非均相Fenton处理兰炭废水高雯雯;弓莹;闫龙;陈碧【摘要】以苯甲醇为溶剂,采用水热法制备LaCoO3钙钛矿型催化剂,研究LaCoO3钙钛矿型催化剂非均相Fenton处理兰炭废水的最佳工艺条件及催化机理.结果表明,在过氧化氢用量3 mL、LaCoO3钙钛矿型催化剂用量0.2 g、pH=4和反应温度25 ℃条件下,LaCoO3钙钛矿型催化剂非均相Fenton处理兰炭废水的COD去除率达到72.7%,通过自由基捕获剂叔丁醇的加入及一级动力学模型研究非均相Fenton过程机理.%Using benzyl alcohol as the solution,perovskite-type LaCoO3 catalyst was prepared by hydrothermal method.The best process condition and catalytic mechanism of heterogeneous Fenton reaction for degradation of semi-coking waste water over perovskite-type LaCoO3 catalyst were investigated.The results showed that COD removal rate of semi-coking waste water reached 72.7% under the optimal condition as follows:H2O2 amount 3 mL,perovskite-type LaCoO3 catalyst dosage 0.2 g,pH=4 and reaction temperature 25 ℃.The mechanism of heterogeneous Fenton reaction was studied by adding free radical scavenger t-butyl alcohol and first order kinetics model.【期刊名称】《工业催化》【年(卷),期】2017(025)003【总页数】5页(P71-75)【关键词】催化化学;钙钛矿;LaCoO3催化剂;非均相Fenton;兰炭废水;叔丁醇【作者】高雯雯;弓莹;闫龙;陈碧【作者单位】榆林学院化学与化工学院,陕西榆林 719000;榆林学院化学与化工学院,陕西榆林 719000;榆林学院化学与化工学院,陕西榆林 719000;榆林学院化学与化工学院,陕西榆林 719000【正文语种】中文【中图分类】O643.36;X703兰炭废水中含有大量的有毒有害物质，污染物色度高，属于难生化降解的高浓度有机工业废水[1]。

Fluorine-doped tin oxide catalyst for glycerol conversion to methanolin sub-critical water

J.of Supercritical Fluids 120(2017)366–378Contents lists available at ScienceDirectThe Journal of SupercriticalFluidsj o u r n a l h o m e p a g e :w w w.e l s e v i e r.c o m /l o c a t e /s u p f luFluorine-doped tin oxide catalyst for glycerol conversion to methanol in sub-critical waterWan Zurina Samad a ,b ,c ,∗,Motonobu Goto b ,∗,Hideki Kanda b ,Wahyudiono b ,Norazzizi Nordin a ,Kin Hong Liew a ,Mohd Ambar Yarmo a ,Muhammad Rahimi Yusop a ,daSchool of Chemical Sciences &Food Technology,Faculty of Science &Technology,Universiti Kebangsaan Malaysia,43600UKM Bangi,Selangor Darul Ehsan,Malaysia bDepartment of Chemical Engineering,Nagoya University,Furo-Cho,Chikusa-Ku,Nagoya 464-8603,Japan cDepartment of Chemistry,Kulliyyah of Science,International Islamic University of Malaysia,Jalan Sultan Ahmad Shah,Bandar Indera Mahkota,25200Kuantan,Pahang Darul Makmur,Malaysia dKluster Perubatan Regeneratif,Institut Perubatan dan Pergigian Termaju,Universiti Sains Malaysia,13200Bertam Kepala Batas,Pulau Pinang,Malaysiaa r t i c l ei n f oArticle history:Received 19December 2015Received in revised form 11May 2016Accepted 30May 2016Available online 2June 2016Keywords:Sub-critical waterFluorine-doped tin oxide Glycerol conversion MethanolHeterogeneous catalyst Biomassa b s t r a c tIn this study,a method for the catalytic conversion of glycerol to methanol in sub-critical water (subCW)is proposed.Glycerol conversion to methanol using the subCW method is a new attempt to the best of the authors’s knowledge and this process was compared with the conventional hydrogenolysis method.For the ﬁrst time,ﬂuorine-doped tin oxide (FTO)was applied as a novel heterogeneous catalyst for the conversion of glycerol to methanol.The sub-critical reaction was conducted under optimal and mild conditions at a reaction temperature of 300◦C,reaction time of 30min,and at a low pressure sufﬁcient to maintain the liquid phase.Initial feedstock (glycerol)concentration and catalyst amount of 20wt%and 0.01g respectively,were utilized and glycerol conversion and methanol selectivity were measured using gas chromatography-ﬂame ion detector (GC-FID)analysis.Optimum glycerol conversion of ∼80%was achieved,with methanol as the major product with a selectivity of ∼100%.The subCW method can also be applied for extraction processes as well as biomass conversion by optimizing some parameters such as reaction time,catalyst amount,reaction temperatures,and catalyst cyclability.©2016Elsevier B.V.All rights reserved.1.Introduction1,2,3-Propanetriol also known as glycerol has become an impor-tant feedstock that can be converted into value-added chemicals.Glycerol has been described as a beneﬁcial biomass resource with a various functions for renewable energy sources [1–3].Glycerol is produced as an abundant side product during the transesteriﬁca-tion of palm oil fruit to produce biodiesel [4,5].The production of glycerol has been continuously increasing with increase in the pro-duction of biodiesel.The production of biodiesel rapidly grew from 1million tons in 2000to 10million tons in 2010.For every 9kg of biodiesel production,around 1kg of crude glycerol is produced [6,7].Owing to the oversupply of glycerol [8],a number of cat-alytic reactions have received attention from researchers and have∗Corresponding authors at:Department of Chemical Engineering,Nagoya Uni-versity,Furo-Cho,Chikusa-Ku,Nagoya 464-8603,Japan.E-mail addresses:wzurina@.my (W.Z.Samad),mgoto@nuce.nagoya-u.ac.jp (M.Goto).been widely monly,glycerol can be converted into chemicals or fuel using various techniques such as oxidation,fer-mentation,dehydration,carboxylation,esteriﬁcation,gasiﬁcation,and reduction (hydrogenolysis)[6,9].The hydrogenolysis of glyc-erol has become the most popular and widely used technique for glycerol conversion.This method involves the simultaneous addi-tion of hydrogen gas and it is easy to produce chemical molecular fragments using this method.However,an important demerit of the hydrogenolysis process is the consumption of hydrogen gas.In the present study,we have attempted to design a new tech-nique involving subcritical water (subCW)to convert glycerol.The subCW method is performed without an external hydrogen gas.In the subCW method,water acts as a solvent as well as a reactant [10–12].Thus,undermost sub and supercritical condition,water is considered a promising reagent for conducting degradation pro-cess.In addition,a shorter reaction time of 30min is also achieved in the subCW method compare to hydrogenolysis in which the optimum reaction time ranges from 6to 24h [13,14].Secondly,the subCW method can be a new method for the con-version of glycerol to methanol (MeOH),which is a rare glycerol/10.1016/j.supﬂu.2016.05.0410896-8446/©2016Elsevier B.V.All rights reserved.W.Z.Samad et al./J.of Supercritical Fluids120(2017)366–378367conversion product and most difﬁcult to produce.Glycerol conver-sion commonly leads to the formation of three carbon diol products namely1,2-propanediol(1,2-PDO)and also1,3-propanediol(1,3-PDO)with1,2-PDO as the promising product.Meanwhile,ethylene glycol(EG)is produced as a degradation intermediate product,fol-lowed by1-propanol(PrOH)and2-propanol(2-PrOH)as excess products during hydrogenolysis[4–6,8–10,13,15–19].In our study, we attempted to produce MeOH,which is known to be among the most proﬁtable chemicals and a fuel source in the chemical indus-try.The selective conversion of glycerol to MeOH by the subCW method requires the cleavage of C O bond by the H2sources from water which acts as the solvent.As a result of this step,the conver-sion process is green and non-toxic.Further,the sub-critical system between the liquid and gas phase involves the dissociation of C C bonds(covalent bond)in the glycerol molecule.Besides this,the C C and C O bonds are also easily dissociated at high tempera-tures or with hydrothermal water.The subcritical process is mainly involved during thermal cleavage in which various radicals can be obtained,and is observed to stabilize upon the addition of hydro-gen which originates from the donor solvent[10,20].Therefore, subCW is a suitable alternative method and medium for glycerol conversion.It has been reported that the uses of a heterogeneous cata-lyst during glycerol conversion can yield better conversion and product selectivity.In the literature,acid,basic,or metal sup-ported catalysts such as Cu/boehmite,Ru/TiO2,Cu/SiO2,Cu/MgO, Ni/ZnO,Ru/bentonite-TiO2etc.[5,21–24]have been used.There are some reports claiming that acid catalysts play an important role in the dehydration of glycerol with EG produced as an intermediate molecule during the generation of1,2-PDO.The production of EG simultaneously increases conversion and selectivity[25].The same argument has also been proposed for basic catalysts,but with a different intermediate,which under basic conditions can aid the dehydrogenation of glycerol to glyceraldehyde andﬁnally to1,2-PDO[7].Feng et al.[7]also proved that improved conversion and product selectivity can be achieved under basic conditions.There-fore,considering the importance of catalyst properties in enhancing glycerol conversion,we attempted to develop a new heterogeneous catalyst namelyﬂuorine-doped tin oxide(FTO)with amphoteric and conducting properties[26,27]for glycerol conversion to MeOH by the subCW method.In the present study,we mainly focused on the conversion of glycerol to MeOH in subCW with FTO as the catalyst.To the best of our knowledge,this is theﬁrst study on glycerol conversion to produce MeOH as a major product by the subCW method with FTO as a heterogeneous catalyst.The effects of various parameters such as temperature,reaction time,and catalyst cyclability on glycerol conversion and product selectivity were investigated.2.Materials and experimental methods2.1.ChemicalsPowder of FTO,which was used as the catalyst,was purchased from Walkers&Keeling Company.Glycerol with99.8%purity was purchased as the feedstock material from Sigma Aldrich.Distilled water was used as the solvent for feedstock dilution.Solvents such as MeOH,ethanol,1,2-PDO,and EG were purchased from Wako Pure Chemicals Industries,Ltd.(Osaka,Japan),and were used as standard solutions for gas chromatography-ﬂame ion detector (GC-FID)analysis.The purities of these chemicals were∼99.5%. 1,4-Butanediol(purity∼99%)was used as the internal standard for the GC instrument and was obtained from Sigma Aldrich.All the chemicals were used as-received without further puriﬁcation processes.2.2.Catalyst preparationThe FTO catalyst powder was activated by sintering at a tem-perature of450◦C for3h.This process activated the surface and pores of the catalyst providing active surface sites for the reaction to occur.After the sintering process,the FTO catalyst powder was stored in a sample bottle,and purged with argon gas to prevent exposure to moisture.2.3.SubCW reactor experimental procedureThe experiments were carried out using a stainless steel tube reactor with a capacity of 5.0cm3,(16.0mm o.d, 6.0mm and 180.0mm in length)fabricated at AKICO Co.,Ltd.,Tokyo,Japan. The glycerol feedstock was prepared at a concentration at20wt% (2mL),to which0.01g of FTO catalyst was mixed in the reactor. The reactor was then sealed and tightened to prevent leakage dur-ing the reaction.Subsequently,the reactor was placed in an electric furnace(Isuzu Co.Ltd.,model NMF-13AD),heated to573K,and shaken using a mechanical device.The reaction was conducted for 30–180min.After the reaction,the reactor was removed from the electric furnace and quenched in a water bath at ambient tem-perature.After the cooling process,the liquid and catalyst were collected and separated using centrifugation andﬁltration pro-cesses.After each reaction,the FTO catalyst was collected and washed3times with distilled water in order to remove any reac-tant,product or impurities that may have been stuck to the catalyst. This cleaning process allowed the catalyst to be tested for stly,the reaction products were analyzed using GC-FID,and glycerol conversion and product selectivity were calculated using the following equation:Glycerol conversion(%)=Moles of glycerol consumedMoles of glycerol initially charged×100 Selectivity(%)=Moles of carbon in a speciﬁc productMoles of carbon in all detected product×1002.4.CharacterizationThe catalyst properties and catalyst performance were char-acterized next.The surface morphology and particle size of the catalyst were analyzed by using aﬁeld-emission scanning electron microscope(FE-SEM:with Supra55vp model)and transmission electron microscope(TEM:Super Twin Philips Technai20).Mean-while,the catalyst composition was analyzed by energy dispersive X-ray spectroscopy(EDX)and X-ray photoelectron spectroscopy (XPS),Kratos(XSAM HS).X-ray diffraction(XRD:Bruker DB advance)was used to analyze the structure and crystallinity of the catalyst.XRD pattern were acquired in the2␪range of20–80◦). The acidity and basicity properties of the catalyst,were deter-mined using chemisorption measurements by the temperature programmed desorption method(TPD).Two types of gases,namely 5%NH3in95%He,and5%CO in95%He were used for the acidity and basicity tests respectively.In addition,using the temperature programmed reduction(TPR)method,the catalyst reduction phase and oxidation state were determined.These experiments were con-ducted in the temperature range of30–850◦C in the presence of a mixture gases composed of10%N2and90%H2.Both the TPD and TPR analysis instruments were procured from Micromeritics Autochem II model.The catalyst performance was analyzed using gas GC-FID(model series of Shimadzu,GC-2014).The yield was quantiﬁed by the HP-Innowax column(Agilent Technologies,length30m,i.d.0.250mm,ﬁlm0.25␮m).The temperature program was run from45(3)to 240(5)with a gasﬂow rate of5mL/min.1,4-Butanediol was used368W.Z.Samad et al./J.of Supercritical Fluids 120(2017)366–378Fig.1.Surface morphology and particle size analysis of FTO catalyst (a)FE-SEM image and (b)TEM image.as the internal standard for calculating the glycerol conversion and product selectivity.3.Results and discussion3.1.Catalyst propertiesFig.1shows the surface morphology (FE-SEM)and particle size images (TEM)of the FTO catalyst.The FTO catalyst particles were observed to exhibit a mixture of shapes including spheres and the tetragonal structure.The particle size was observed to be in the range of 20–100nm.Mapping analysis was also conducted to identify the exact exis-tence of ﬂuoride element in the FTO molecule.As shown in Fig.2,the ﬂuoride cluster on the surface was well-dispersed proving the existence of ﬂuoride in the FTO molecule even after the high-temperature calcinations process.The ﬂuoride cluster in the FTO molecule was assumed to have chemical bonding in addition to strong physical bonding.The com-position of the FTO catalyst was studied using EDX,which revealed the presence of all the important elements of FTO,namely tin (Sn),oxygen (O),and ﬂuorine (F).This was supported by the XPS elemen-tal study whose results are summarized in Table 1.The composition of SnO 2was also studied for comparison.XRD patterns of the FTO catalyst are illustrated in Fig.3.The structure and crystallinity of the FTO catalyst were determined by comparison with XRD patterns with the JCPDS numbers:SnO 2:41-1445and ﬂuorine:74-6155.The XRD pattern of the FTO catalyst was overlaid with the XRD pattern of SnO 2in order to determine any differences in the crystal structure with the addition of the ﬂuoride phase.The FTO catalyst and SnO 2exhibited rather similar diffraction peaks.In addition to the peaks in SnO 2,there were some important new peaks detected corresponding to the ﬂuoride phase in FTO at 2␪values of 38.9and 42.6◦.Moreover,some of the peaks corresponding to the ﬂuoride phase were found to overlap with the peaks of the SnO 2phase,perhaps due to the fact that ﬂuoride element is well-dispersed on the SnO 2surface as well as within the pores,and also because of the small size of the ﬂuoride clusters.This phenomenon has also been reported by Ma et al.[4],in cases where Ru clusters were interca-Table 1Summary on the compositions of the FTO and SnO 2catalysts determined by EDX and XPS techniques.SampleComposition (atomic%)/XPSComposition (atomic%)/EDXSnOFSnOFPristine FTO 30.449.59.9125.674.30.14Pristine SnO 232.457.9N.d24.775.3N.dN.d:not detected.Table 2Crystallite size calculations using Sherrerr equation of FTO and SnO 2catalysts.LatticeCrystallite size of SnO 2(nm)Crystallite size of FTO (nm)(110)12.512.8(101)11.912.1(200)12.312.3(211)10.811.0(310)10.010.1(301)9.69.9(321)7.79.3Fluorine peak (42.6◦)N.d13.2N.d =not detected.Table 3Summary of the physical and chemical properties of FTO and SnO 2catalysts by using BET technique.SampleS ABET ,m 2/g −1V p ,cm 3/g −1D p ,nmPristine FTO 9.10.0412.6Pristine SnO 26.10.0213.8lated into an Al 2O 3support.In that case,no diffraction peaks were observed which might also be due to the good dispersion of the Ru cluster onto the support material.The presence of ﬂuoride cluster in the FTO molecule was observed to cause an increase in the intensity of most of the peaks compared to the SnO 2molecule especially for peaks corresponding to the (110),(101),(200),(211),(220),and (310)crystal planes.In order to further conﬁrm the existence of the ﬂuoride cluster in the FTO phase,the crystallite size was calculated using the Scherrerr equation.The crystallite sizes in some lattices were observed to be increased,owing to the intercalation of the ﬂuoride cluster into the FTO phases.A comparison of the crystallite sizes between SnO 2and FTO is shown in Table 2.The surface area,pore volumes,and pore sizes of the FTO catalyst were analyzed using nitrogen adsorption-desorption isotherms (BET method).Table 3summarizes the physical properties of the FTO catalyst.The FTO catalyst exhibited well-deﬁned adsorption and desorption hysteresis loops indicating that the FTO catalyst is a mesoporous material.From the BET analysis,FTO was observed to possess a larger sur-face area than SnO 2.This is probably because the ﬂuoride cluster can enhance the formation of new active surface sites for chemi-cal reactions.Fluoride clusters may be intercalated within the FTO pores,and some of the ﬂuoride clusters may be bonded physically on the surface.Meanwhile,while the pore volume of the FTO cat-alyst increased,the pore diameter decreased.These results show that,a signiﬁcant amount of ﬂuoride cluster can enter FTO and thus,can provide more active sites.This was supported by the smaller pore diameter,which can prevent ﬂuoride from easily leaching out.W.Z.Samad et al./J.of Supercritical Fluids 120(2017)366–378369positional analysis of FTO catalyst (a)ﬂuorine mapping analysis and (b)EDX spectra of FTO elementalstudy.Fig.3.X-ray diffraction pattern of (a)FTO and SnO 2,and (b)ﬂuorine cluster peak.The amphoteric properties of FTO were quantiﬁed by the TPD analyses of NH 3for acidity and CO 2for basicity properties.As com-parison,the chemisorptions proﬁles of FTO catalyst and SnO 2were included as illustrated in Fig.4(a)and (b)respectively.In Fig.4(a),the TCD signals indicates the NH 3desorption proﬁles for FTO cata-lyst and SnO 2which exhibited a broad peaks associated with weak,medium,and strong sites in the acid desorption areas which proved that both materials contributed an acidity properties as reported [28,29].However,SnO 2were observed to have a signiﬁcant low acidity as there is no desorption peak were observed in strong acid desorption area.Meanwhile,for the basicity properties,the TPD CO 2proﬁles of FTO catalyst and SnO 2were showed in Fig.4(b).Overall,the desorption peaks for both samples was seen in the weak and also strong basic desorption areas.Signiﬁcant high intensity desorption was found for FTO catalyst compared to SnO 2which it was suggested that the basicity site was enhanced by ﬂuoride ions.It was proposed that FTO structure system is a dative covalent bond which involving the SnO 2phase represented as acid lewis and ﬂuoride ions as base lewis [30].In this preliminary study,the TPD analysis was able to prove that FTO catalyst contains an amphoteric properties.Due to our knowledge,FTO structure have never been proposed by previous researchers,therefore further study need to be conducted in the future.The reducibility of the FTO catalyst was determined by TPR tech-nique.Fig.5presents the hydrogen TPR proﬁles and it was observed only one signiﬁcant broad peak appeared in the temperature range of 600–800◦C.The appearance of the peak indicates the reduction of SnO 2to metallic Sn as well as ﬂuoride cluster reduction.The FTO catalyst is also observed to have a much higher reduction in tem-perature compared to SnO 2.The SnO 2powder exhibited an earlier reduction phase and broader peak probably due to the fact that SnO 2is fully reduced at that stage.Meanwhile,the FTO catalyst had a sharper peak,probably because of the presence of FTO oxide phases that still remained without been reduced.This result shows that FTO has very good thermal and chemical stability,thereby suggesting that the higher temperature of reaction did not cause any signiﬁcant changes or exert any effect on the catalytic activ-ity of FTO.This result was supported by thermogravimetry analysis (TGA)in which the FTO catalyst was maintained without a speciﬁc degradation isotherm up to 1200◦C (isotherm not shown).Next,the chemical states and structural properties of the FTO catalyst were investigated by the XPS technique.XPS analysis was conducted to further conﬁrm ﬂuoride cluster presence and deter-mine the chemical states of the elements.A wide scan XPS spectrum of the FTO catalyst powder is shown in Fig.6.The spectrum revealed that the FTO catalyst contained all the elements expected and a370W.Z.Samad et al./J.of Supercritical Fluids120(2017)366–378Fig.4.TPD proﬁles on NH3and CO2desorption of FTO and SnO2catalysts(a)acidity properties,and(b)basicity properties.signiﬁcant peak attributed toﬂuoride phase was clearly seen.The peaks in the spectra were assigned as follows:Sn3d(487.1eV),O 1s(531.1eV),and F1s(684.7eV).These signals match very well in location with those reported by Martinez et al.[28].The C1s sig-nal peak(Fig.7a)at the binding energy of284.5eV was used as the standard peak for the curveﬁtting process.Curveﬁtting of the XPS narrow scan spectra were conducted for all the elements as shown in Fig.7.The F1s signal in Fig.7(b)shows only one major peak which was assigned to the F Sn bond.However,the intensity of the F1s peak was quite low,probably owing to the inhibition of the chemi-cal bonding of F Sn inhibits in the small range.Thus,as conclusion most of theﬂouride cluster existed in the form of free electrons asﬂuoride ions.Theﬂouride cluster was assumed to be packed within the interspaces of the FTO molecules.Consequently,some of theﬂuoride was bonded chemically,whereas some were physi-cally bonded to the surface and between the surfaces sinceﬂuoride peaks of moderate intensity were detected.Fig.7(c)shows the XPS narrow scan spectrum of the Sn3d signal peak,which includes two major curveﬁttings.Theﬁrst peak at a binding energy of487.1eV, was attributed to Sn O and SnO2bonding,whereas the second peak at a binding energy of487.9eV was assigned to the Sn F bonding [26].The oxidation state of Sn was determined to be Sn4+which was also supported by theﬁndings of Martinez et al.[28].Amanul-lah et al.[29,31]also obtained Sn3d5/2,peaks at486.4eV using the XPS technique.However they failed to notice theﬂuorine peaks of FTO which contributes to Sn F bonding.In the case of O1s,there is one signal peak with two curveﬁttings(Fig.7d)corresponding to O Sn and bridging oxygen(C O and H2O)and appearing at binding energy values of531.5and532.7eV respectively.Previous researchers were unable to determine the exact chem-ical structure of FTO.FTO was only known as a doped material and its chemical formula was representd as SnO2:F.However,it has been proved that theﬂuoride cluster introduced during calcina-tion at high temperatures can be observed through XPS analysis.In this study,we have attempted to proposed the structure of the FTO molecular system which is shown in Scheme1.W.Z.Samad et al./J.of Supercritical Fluids 120(2017)366–378371Fig.5.TPR proﬁles on reducibility analysis of FTO and SnO 2catalysts.Fig.6.XPS wide scan spectrum of FTO catalyst.3.2.Catalyst performance in SubCW (optimization of reaction parameters)Studies on the degradation of glycerol in subCW processes have been conducted by several researchers in the presence as well as absence catalysts.It has been proved that the sub-critical technique can potentially convert glycerol to some value-added chemicals such as acrolein,acetaldehyde,formaldehyde,acetone,allyl alcohol,and other unidentiﬁed products [20,32–35].Most of the previous research studies reported high glycerol conversion,but rather low product selectivity.Reaction temperature and reac-tion time were observed to be the most important parameters inﬂuencing glycerol degradation and product selectivity.Table 4summarizes the results of previous studies on glycerol degradation using subCW [32,33,36–38].Catalyst performance activity during the subCW conversion of glycerol to MeOH was evaluated.The inﬂuence of reaction tem-perature,reaction time,glycerol concentration,catalyst amount,and cyclability on glycerol conversion and product (MeOH)selec-tivity were investigated for determining the catalytic activity of FTO.Scheme 2shows a suggested chemical pathway for directly372W.Z.Samad et al./J.of Supercritical Fluids 120(2017)366–378Fig.7.XPS narrow scan spectra of FTO catalyst (a)C 1s signal,(b)F 1s signal,(c)Sn 3d signal,and (d)O 1s signal.MeOH production using subCW technique.Further study on the chemical mechanism will be conducted in the future.3.2.1.Inﬂuence of reaction temperatureIn the sub-critical ﬂuid technique,the reaction temperature is an important factor governing the optimum reaction conditions andW.Z.Samad et al./J.of Supercritical Fluids 120(2017)366–378373Scheme 1.Suggested structure of the FTO catalyst.Table 4Comparison studies of glycerol degradation activity by the sub-critical water process.Sample/catalystGlycerol conversion (%)Reaction temperature (K),pressure (MPa)Reaction time (min)/(s)References Zinc sulphate 80573K,34.5MPa 16s [35]Ru/ZrO 2Almost complete conversion 823K,35MPa 8s [31]Without catalyst 13.8673K,34.5MPa 21s [32]Without catalyst 84553K,10MPa 90min [36]Without catalyst28740K,450MPa98.1s[37]Fig.8.Effect of reaction temperature on glycerol conversion and methanol selectivity.can exert signiﬁcant effect on the catalytic performance.Several temperatures in the range of 423–573K were tested.Fig.8shows the effect of reaction temperature on the catalytic activity towards glycerol conversion over the FTO catalyst.The conversion of glycerol signiﬁcantly increased with increase in the temperature from 423to 573K.Both glycerol conversion and MeOH selectivity increased from zero to nearly 80%and 100%,respectively.At a lower temperature,water,which acts as a reac-tant as well as solvent,has a smaller ion product,resultinginScheme 2.Suggested pathway for glycerol conversion to MeOH.glycerol degradation.When the temperature is increased close to the critical conditions,water can transform into an excellent sol-vent for organic compounds,owing to decrease in the dielectric constant.At this stage,water has higher H +and OH −ion concen-trations than water at lower temperatures.Thus,the dissociation of water near the critical point can generate high concentrations of H +and allow acid-catalyzed organic reactions without the addition of an acid co-catalyst.This contention is supported by the results of Qadariyah et al.[20]who claimed that increasing the reaction temperature up to 573K encouraged acrolein production and glyc-erol degradation.It was found that a higher temperature favored both glycerol conversion as well as MeOH selectivity.The temper-ature of 573K was concluded to be optimal for converting glycerol to MeOH by subCW method.3.2.2.Inﬂuence of reaction timeGlycerol conversion and MeOH selectivity over different reac-tion times were investigated and the results are shown in Fig.9.374W.Z.Samad et al./J.of Supercritical Fluids 120(2017)366–378Fig.9.Effect of reaction time on glycerol conversion and methanol selectivity.Almost all the reaction times yielded high glycerol conversion with high MeOH selectivity in the range of 80–100%.However,the reac-tion time of 30min was determined to be optimal since at longer reaction times,some kind of resin or tar was observed on the cata-lyst,which caused difﬁculties in the catalyst re-collection process.The generation of resin and tar at high reaction times suggest that exposure for long times under subCW conditions probably encour-age the full glycerol liquefaction,thereby promoting a polymeric C C bond formation.Generally,in hydrothermal or sub-critical water reaction which involving degradation of glycerol,the gaseous products were able to be produced such as hydrogen,methane,and also carbon dioxide.However,in this initial phase of study,we have not fully explored the expected gaseous products and it will be investigated in the future study.3.2.3.Inﬂuence of catalyst weightIn order to understand the inﬂuence of the amphoteric proper-ties of the FTO catalysts on glycerol conversion,we carried out the reaction by varying the catalyst weight in the range of 0.01–0.09g,as shown in Fig.10.A nearly constant glycerol conversion of ∼80%was observed independent of the amount of catalyst.This showed that,increases of both acid and basic sites (increased on catalyst weight)of FTO catalyst give stable activity.Glycerol conversion processes,usually involved both acidic and basic sites and the reac-tion is known as a bi-functional reaction.Further,both acid and basic sites on the catalyst are assumed to enhance C C and C H bond cleavage at an optimum rate.Despite that,as the existence of ﬂuoride ions which play role as base lewis,it was considered would contributed to the double dehydration which perform better under basic conditions,and the research was done by Haider et al.[39]where they proposed that the basic catalyst can enhanced the reduction process leads to methanol and ethanol production.The equilibrium between the amount of acid and basic sites on the FTO catalyst has been discussed previously when discussing the results of the TPD analysis.This equilibrium could be the reason for the constant values of glycerol conversion and product selectivity.In addition,the stable performance of the catalyst may also be due to the conducting properties of FTO.The presence of a large amount of cloudy and free electrons is assumed to contribute to the reaction.As stated previously,subCW may be involved in the reduction as well as hydrolysis processes.Overall,at all the FTO catalyst weightstested,good and stable glycerol conversions were obtained.Other than that,it can be summarized that either small or larger amount of FTO catalyst (small or higher amphoteric properties),it has good ability to convert glycerol.Meanwhile,the selectivity of MeOH was observed to nearly100%in all the cases,except for the catalyst amount of 0.03g,in which case,the selectivity slightly decreased to ∼89.6%.It was considered at this catalyst amount,the side product of glycerol conversion,1,2-PDO was detected.This might be due to the cessation of C C bond dissociation and the occurrence of the reverse reaction,which is efﬁcient in selectively cleaving the C O bond.Other than that,it might be due to catalyst in-situ oxidation,which enhanced the pro-duction of MeOH reaches an optimum value and therefore glycerol tends to be converted to 1,2-PDO [22].As summary,it was con-sidered that the amphoteric properties did inﬂuence the glycerol conversion and methanol selectivity with constant catalytic activity at lower and higher level of amphoteric properties.3.2.4.Inﬂuence of glycerol concentrationFig.11presents the glycerol conversion and MeOH selectiv-ity over the FTO catalyst as a function of glycerol concentration in the range of 20–80wt%.The conversion of glycerol was found quite stable with a slightly decreases as the glycerol concentration increased.The highest glycerol conversion was observed at glyc-erol concentration of 20wt%with 80%conversion and the lowest conversion is 73%at concentration of 40wt%respectively.This con-version stability was due to at sub-critical point,water inhibits an unique properties which it can boost higher ionic products of H +and OH −ions which can catalyzed the organic reaction [20].As at higher temperature,there is an increase in the diffusion rate and also decrease in the viscosity which causes the hydrogen bonding becomes weaker with low dielectric constant,thus water behaves like a non-polar solvent and becoming capable of dissolving glyc-erol molecule.High diffusion of the glycerol liquid can enhance the catalytic activity where glycerol molecules have high contact with FTO catalyst active surfaces to allow C C and C H bond scission [11,32,40].Previous studies have suggested that the conversion rate of glyc-erol is usually high at low glycerol concentrations,because the amount of active surface area for catalytic activity is constant even though at high concentration of glycerol.This is also supported by。

油橄榄叶提取物对铅中毒小鼠大脑海马组织抗氧化酶及NO与NOS的影响

一
氧化氮合酶（ＮＯＳ活性及丙二醛（Ａ））ＭＤ
、
，
变化・结果表明：与模型对照组相比，鼠灌胃ＯＩ小Ｅ后海马组织ＳＤＯ
、
ＣＡＴ、ＮＯ、ｓ水平均升高，Ａ含量降Ｎ０ＭＤ
、
低・明油橄榄叶提取物对铅中毒小鼠有一定的疗效说
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Oxide ion diffusion in Ba-doped LaInO3 perovskite A molecular dynamics study

钡掺杂的LaInO3钙钛矿中氧离子扩散的分子动力学研究Dae-Seop Byeon , Seong-Min Jeong , Kuk-JinHwang , Mi-Young Yoon , Hae-Jin Hwang ,Shin Kim , Hong-Lim Lee摘要：应用传统的分子动力学技术的计算机研究被用来研究立方形的钡掺杂的LaInO3钙钛矿中氧离子扩散机制。

钡掺杂的LaInO3钙钛矿形成的氧空穴作为氧离子扩散的电荷载体。

以前的实验研究表明随着氧空穴的增加钡掺杂的LaInO3钙钛矿的离子传导性能增加，这种现象不能完全通过实验解释。

因此，我们的研究通过分子动力学模拟了单个氧空穴的扩散途径。

研究结果表明，钡掺杂的钙钛矿形成了很窄的瓶颈，这个瓶颈是氧离子移动的障碍。

我们的计算结果表明钡掺杂的LaInO3钙钛矿的离子传导性能受到掺杂的钡的局部分布情况的影响。

1.简介三元的ABO3型钙钛矿的结构如图1所示，这种钙钛矿结构能承受大量元素的掺杂。

这样的掺杂能改变钙钛矿材料的性能，赋予了这种材料高效的氧离子传导性能。

这种性能使钙钛矿材料成功地应用在了固体电解质溶液、电解槽、氧泵和电流型氧传感器方面。

在过去的三十年，大量的研究群组试图通过A位和B位氧离子的掺杂提高氧离子的传导性能。

众所周知A位掺杂的LaBO3钙钛矿是氧离子导体，这种性质已经吸引了大量人的兴趣。

在所有的这些材料中，钡掺杂的LaInO3，（Ba x La1-x）IO3-0.5x展现除了一些有趣的特性。

当x从0.4到1变化时这些材料只存在单一的相。

当x处于0.4到0.5之间时单一相的晶体对称性为立方型，当x处于0.5到0.8之间时为四角形，当x大于0.8时为斜方晶系。

当钙钛矿材料为立方晶型时有最高的离子传导性能，即x从0.4到0.5变化时。

这种材料在氧压高时即体现了氧离子传导性能，也体现了p型传导性能。

但是在氮气环境下，它只表现出氧离子的传导性能。

简单异喹啉类化学成分结构式的英文

简单异喹啉类化学成分结构式的英文
异喹啉类化合物在药物研究和设计中广泛应用，因此了解其化学成分的命名和结构式是非常重要的。

以下是几种简单异喹啉类化合物的化学成分结构式及其英文名称：
1. 喹啉（Quinoline）
结构式：
英文名称：Quinoline
2. 氢氧化喹啉（Hydroxyquinoline）
结构式：
英文名称：Hydroxyquinoline
3. 氧化喹啉（Oxyquinoline）
结构式：
英文名称：Oxyquinoline
4. 8-羟基喹啉（8-Hydroxyquinoline）
结构式：
英文名称：8-Hydroxyquinoline
5. 8-羟基喹啉-5-磺酸钠（8-Hydroxyquinoline-5-sulfonic acid sodium）
结构式：
英文名称：8-Hydroxyquinoline-5-sulfonic acid sodium
以上是几种简单异喹啉类化合物的化学成分结构式及其英文名称，希望能够帮助您更好地了解这些化合物。

不同金属取代Finke型多金属氧酸盐显色检测多巴胺的催化性能

第 22 卷第 3 期 2021 年 5 月
北华大学学报( 自然科学版) JOURNAL OF BEIHUA UNIVERSITY( Natural Science)
Vol. 22 No. 3 May 2021
文章编号:1009-4822(2021)03-0380-07
DOI:10. 11713 / j. issn. 1009-4822. 2021. 03. 021
第3 期
段喜鑫,等:不同金属取代 Finke 型多金属氧酸盐显色检测多巴胺的催化性能
381
检测方法[11-15] .
在显色免疫检测过程中,生物酶很容易受到外界环境的影响而变性,且制备、储存耗时长,价格昂贵,
过程复杂. 与天然酶相比,纳米材料具有更好的稳定性,其中,金纳米粒子在显色检测 DA 领域应用较为广
P2 W15 M4 系列多酸催化剂的红外光谱见图 3. 由图 3 可见:在 1 170、970、950、615 cm-1 处均出现 4 个特征峰,分别归属磷氧振动(P-Oa )、钨氧振动( W-Od ) 和桥氧对称伸缩振动( W-Ob1 -W、W-Ob2 -W),与文献[30] 报道一致,证明 P2 W15 M4 保持了 Finke 型结构. 图 4 为 P2 W15 M4 的 XRD 谱图. 由图 4 可见:合成的样品在 2θ 为 7°、16°、18°和 28°的 4 个特征峰与 Finke 型多酸化合物的衍射峰位置基本一致[30] ,与 IR 表征结果一致.
原性能的金属氧簇化合物. 通过调控多酸结构、取代金属种类和数目可获得不同氧化性的 POMs. WANG
等[26] 首次报道了 H3 PW12 O40 的过氧化物酶活性,采用 POMs / H2 O2 / TMB 体系用于显色检测 H2 O2 或者葡萄糖[27-28] ,之后该团队又制备了 SiW10 Fe2 与叶酸复合的新型多酸催化剂,用于癌细胞和 H2 O2 的显色检测[29] . 本研究采用不同金属调控多酸的氧化性,制备系列 Finke 型 POMs 催化剂———PW9 M4( M 为 Co、Cu、 Mn 和 Zn) 和 P2 W15 M4( M 为 Co、Cu 和 Zn) ,开发在水相中简单、快速、高选择性显色检测 DA 的催化体系, 研究不同反应条件、干扰物质对显色检测的影响.

聚多巴胺对氧化钨膜电致变色性能的影响探究

06092
2021 年第 6 期 (52)卷
图3 添加0mL(a),0.3mL(b),0.6mL(c),1.0mL(d)和2.0mL(e)PDA 制备的 WO3 电致变色复合膜的扫描电子显微镜图和添加,0.6mL(f)PDA 制备的 WO3 电致变色复合膜的剖面扫描电子显微镜图
Fig3SEMimagesofWO3electrochromiccompositefilmsadded0,0.3,0.6,1.0and2.0mLPDAandSEMsec-
2.1.2 复合膜的 FT-IR 和 XPS分析图4为添加 0 mL,1.0 mLPDA 的 WO3 膜冻干
物与 PTA 冻干物的 FT-IR 测试光谱。FT-IR 测试光谱中的1620cm-1 为 PTA 结合水的 O-H 伸缩振动峰[25],这部分水通过氢键的作用与 PTA 结合,无法通过冻干、干燥的方法除去;960cm-1 为 W = Od 特征峰,879cm-1 为 W-Ob-W 特征峰,802cm-1 为 W-OcW 特征峰,说明通过电化学沉积的方法制备了 Keggin
图2 添加0 mL(a),0.3 mL(b),0.6 mL(c),1.0 mL(d)和2.0 mL(e)PDA 制备的 WO3 电致变色复合膜的原子力显微镜图
Fig2AFMimagesof WO3 electrochromiccompositefilmsadded0,0.3,0.6,1.0and2.0 mL PDA onITO substrate
张旭等:聚多巴胺对氧化钨膜电致变色性能的影响探究
mg/mLPDA 溶液。将氧化铟锡(ITO)玻璃基片清洁后在 PEI溶液中浸泡15h[22],用 N2 吹干。以 Pt为对电极,饱和甘汞电极为参比电极,25 mLPTA 溶液作为电解液 ,分 [23-24] 别加入 0 mL,0.3 mL,0.6 mL,1.0 mL,2.0 mL PDA 溶液,-0.5 V 恒定电压条件下沉积 500s,得到混合不同浓度 PDA 的 WO3 电致变色复合膜。图1为 WO3 电致变色复合膜的结构,混合不同量的 PDA 在电解液中的浓度如表1所示。 1.2 结构分析与测试

liesegang非平衡反应-扩散过程

liesegang非平衡反应-扩散过程非平衡反应是指反应体系达到一定条件后产生的连续现象，其中包括波纹、斑纹、环状等形状的纹理结构。

在化学中，最具代表性的非平衡反应就是liesegang反应。

liesegang反应是在非均匀环境中进行的一种扩散过程，它包含了凝胶体系中的物质扩散和相变等多重过程。

下面将详细介绍liesegang非平衡反应的扩散过程。

liesegang反应最早在19世纪末由德国化学家Raphael Liesegang发现，他观察到了硝酸银和硝酸钠在凝胶环境中反应时产生的很特殊的纹理结构。

在liesegang反应中，通常会使用两种反应物，例如硝酸银和硝酸钠，其中一种反应物会分散在凝胶中，而另一种则会以溶液的形式加入。

反应物的分散和扩散是liesegang反应的核心。

在非平衡反应中，硝酸银和硝酸钠是溶液中的离子形式存在的。

当溶液中有足够的反应物时，反应就会开始发生。

整个反应过程可以分为两个阶段：溶液的扩散和产物的沉淀。

首先，硝酸钠溶液会从已经分散了硝酸银离子的凝胶表面扩散进入凝胶内部。

凝胶的结构会对溶液的扩散速率产生影响，因此在凝胶的不同位置，溶液的扩散速率是不一样的。

当溶液中的反应物浓度达到一定程度时，就会发生反应。

硝酸银离子和硝酸钠通过扩散相遇产生新的沉淀物，这些沉淀物便会在凝胶中形成纹理结构。

liesegang反应的纹理结构是由于反应物的扩散速率和沉淀速率的空间分布产生的。

由于凝胶中硝酸银离子的浓度是不均匀的，而硝酸钠溶液的扩散速率又受到凝胶结构的影响，所以在凝胶中形成了浓度梯度。

这种浓度梯度会导致沉淀物的形成并扩散到周围区域，形成波纹、斑纹等特殊的纹理结构。

liesegang非平衡反应的扩散过程是一个复杂的动力学过程，涉及到凝胶中物质的扩散、变形、相变等多种现象。

凝胶的结构和性质对扩散速率起着重要影响。

一般来说，凝胶的孔隙度越大，扩散速率越快。

因此，可以通过控制凝胶的制备条件、凝胶的成分等来调节liesegang反应的纹理结构。

新型仿生纳米材料可用于去除农业化学污染物

新型仿生纳米材料可用于去除农业化学污染物
作者：陈旭
来源：《科学导报》2021年第51期
近日，中国农业科学院蔬菜花卉研究所质量安全课题组成功制备了新型三元仿生纳米复合材料（LDH@PDA@MPNs），并解析了其结构特征、农业化学污染物吸附识别性能和控制去除机理。

研究表明，贻贝具有惊人的粘附性能和机械性能，这种超强粘弹性主要源于足腺分泌的粘蛋白，其可与三价铁离子通过化学配位和共价交联作用形成高分子网状弹性聚合物。

受此启发，研究团队通过自氧化聚合将多巴胺均匀修饰在二维层状双金属氢氧化物表面，形成聚多巴胺仿生界面（LDH@PDA）;利用含儿茶酚基团的单宁酸与三价铁离子的金属—有机络合反应，在聚多巴胺仿生界面上锚定具有多孔结构的金属—多酚网络，借助PDA和金属—多酚网络的界面协同互作，赋予材料更多表面活性位点，进而提升其粘附和吸附特性。

结合纳米结构表征和物理化学性能分析技术，该研究发现，新型三元仿生纳米复合材料LDH@PDA@MPNs具有隨机卷曲显微结构和海绵状或泡沫状表层，与贻贝附足足丝—黏蛋白的生物有机界面构造和微观形貌十分相似。

该研究为制备新型仿生纳米吸附材料，研发污染控制去除技术，提高农产品质量安全水平提供了新路径。

氧化石墨烯-连续鸟嘌呤碱基DNA复合膜修饰电极用于测定多巴胺

氧化石墨烯-连续鸟嘌呤碱基DNA复合膜修饰电极用于测定多巴胺秦至臻;刘兴华;陈斌;康维钧;牛凌梅【摘要】移取1 g·L-1氧化石墨烯悬浮液5μL滴加在经抛光、清洗的玻碳电极表面,红外灯下烘干后,在0.1 mol·L-1 KH 2 PO 4溶液中,在-0.9 V下沉积600 s,然后将电极浸泡于100μmol·L-1连续鸟嘌呤碱基DNA溶液中1 h,得到氧化石墨烯-连续鸟嘌呤碱基DNA复合膜修饰电极.采用透射电子显微镜、扫描电子显微镜和电化学方法对修饰电极进行了表征,研究了多巴胺在此修饰电极上的电化学行为,结果发现此修饰电极对多巴胺的氧化还原具有明显的电催化作用.在pH 7.0的磷酸盐缓冲溶液中,以50 mV·s-1的扫描速率扫描,记录多巴胺在修饰电极上的差分脉冲伏安曲线,结果发现多巴胺的浓度在5.0×10-7～9.0×10-6 mol·L-1,9.0×10-6～5.0×10-5 mol·L-1内与其氧化峰电流呈线性关系,检出限(3s/k)为3.5×10-8 mol·L-1.方法可用于测定体液和药品中多巴胺的含量,加标回收率在88.0％～106％之间,测定值的相对标准偏差(n=5)小于5.0％.【期刊名称】《理化检验-化学分册》【年(卷),期】2018(054)012【总页数】6页(P1394-1399)【关键词】氧化石墨烯;连续鸟嘌呤碱基DNA;修饰电极;多巴胺;差分脉冲伏安法【作者】秦至臻;刘兴华;陈斌;康维钧;牛凌梅【作者单位】河北医科大学公共卫生学院,石家庄 050017;河北医科大学公共卫生学院,石家庄 050017;河北医科大学药学院,石家庄 050017;河北医科大学公共卫生学院,石家庄 050017;河北医科大学公共卫生学院,石家庄 050017【正文语种】中文【中图分类】O657.1多巴胺(DA)是一种中枢神经递质,通过作用于DA受体产生生理作用,进而调节躯体运动、精神活动、内分泌和心血管活动[1]。

氧代螺环异吲哚啉衍生物的合成及表征

氧代螺环异吲哚啉衍生物的合成及表征翟淼;陈清泰【摘要】Chiral oxo- and spiro- isoindoline derivatives serves as a bio-active structural unit of natural medicines, these compounds had important research value in pharmaceutical and chemical fields. In our experiment, we adopted 1,4-dioxaspiro[4.5] decan-8 -one and phthalic anhydride as the raw material, 2-(1-(4-oxo-bicyclo [4.1.0] hept-1-) propyl-2-) isoindoline-1,3-dione were synthesized by a series of reactions, and the structure of these compouds were characterized by high-performance liquid chromatography ( HPLC ) , liquid chromatography-mass spectrometry ( LCMS) , nuclear magnetic resonane spectrometry ( NMR).%具有手性的氧代螺环异吲哚啉衍生物可作为天然药物的活性结构单元,这些化合物在医药和化工领域具有重要的研究价值。

实验以1,4-二氧螺环[4.5]癸烷-8-酮和苯甲酸酐为原料,经过一系列反应制得2-(1-(4-氧代双环[4.1.0]庚基-1-)丙基-2-)异吲哚啉-1,3-二酮,并利用高效液相色谱(HPLC)、液质联用仪(LCMS)、核磁(NMR)对其结构进行表征。

异喹啉生物碱生物合成

异喹啉生物碱生物合成异喹啉生物碱（Isoquinoline alkaloids）是一类广泛存在于植物和动物中的天然产物，具有多种生物活性和药理作用。

异喹啉生物碱的生物合成是由多个酶催化的化学反应组成的复杂代谢途径。

异喹啉生物碱的生物合成过程通常起始于芳香族氨基酸苯丙氨酸或酪氨酸。

首先，苯丙氨酸或酪氨酸经过酚酸途径被氧化酶催化生成对羟基苯丙氨酸或对羟基酪氨酸。

接下来，通过脱羧酶的作用，对羟基苯丙氨酸或对羟基酪氨酸失去一个CO2分子，生成对羟基苯乙胺或对羟基酪胺。

在异喹啉生物碱的生物合成过程中，最重要的是一个叫做异喹啉合成酶（Isoquinoline synthase）的酶。

异喹啉合成酶催化对羟基苯乙胺或对羟基酪胺的环化反应，形成异喹啉环结构。

这个反应是通过酮醇互变机制完成的，首先生成一个酮型中间体，然后通过内环酯化反应将酮型中间体转化为环结构。

在异喹啉生物碱的生物合成过程中，还存在其他一些重要的酶催化反应，如甲基化、羟基化、氧化、还原等。

这些反应通过调控酶的活性和底物的选择，进一步改变异喹啉生物碱的结构和功能。

异喹啉生物碱具有多种生物活性和药理作用。

其中一些具有抗菌、抗炎、抗氧化、抗肿瘤等药理活性，被广泛应用于药物研发和临床治疗。

例如，白屈菜碱是一种常用的抗心律失常药物；阿托品是一种常用的抗胆碱药物；吗啉胺是一种常用的抗组胺药物。

除了药理作用外，异喹啉生物碱还具有其他一些生物活性。

例如，一些异喹啉生物碱具有昆虫抗性活性，可以作为植物的天然杀虫剂。

此外，一些异喹啉生物碱还具有毒性作用，可以用于控制害虫和杂草的生长。

异喹啉生物碱是一类具有多种生物活性和药理作用的天然产物。

其生物合成是由多个酶催化的化学反应组成的复杂代谢途径。

异喹啉生物碱的结构和功能可以通过调控酶的活性和底物的选择来改变。

异喹啉生物碱在药物研发和临床治疗中有着广泛的应用前景。

同时，异喹啉生物碱还具有其他一些生物活性，如昆虫抗性活性和毒性作用，可以用于农业和环境保护领域。

银杏黄酮苷元对氧化型低密度脂蛋白诱导的人主动脉内皮细胞氧化损伤的影响

银杏黄酮苷元对氧化型低密度脂蛋白诱导的人主动脉内皮细胞氧化损伤的影响王玮玮;何艳;刘兴德【期刊名称】《中国中西医结合杂志》【年(卷),期】2013(33)3【摘要】目的观察银杏黄酮苷元(Ginkgo flavone aglycone,GA)对氧化型低密度脂蛋白(oxidized low-den-sity lipoprotein,ox-LDL)诱导的人主动脉内皮细胞(human aortic endothelial cells,HAECs)氧化应激损伤的保护作用及其机制。

方法体外培养HAECs,分为6组,即空白对照组、ox-LDL组、VitE组以及GA30、60、90mg/L组。

除空白对照组外,其余5组均加入ox-LDL150mg/L复制氧化损伤模型;GA30、60、90mg/L组分别给予相应剂量GA干预;VitE组给予VitE200μmol/L干预。

采用MTT法检测细胞存活率;CM-H2DCFDA荧光探针测定细胞内活性氧(ROS)含量;酶联免疫吸附法检测NADPH氧化酶含量;硫代巴比妥酸法检测丙二醛(MDA)水平;Griess reagent法测定一氧化氮(NO)含量;黄嘌呤氧化酶法测定超氧化物歧化酶(SOD)的含量。

结果与空白对照组(100.00%)比较,ox-LDL组(70.68%)细胞存活率明显降低(P<0.05);VitE组、GA30mg/L组、GA60mg/L组细胞存活率分别为88.95%、83.25%、94.93%,均明显高于ox-LDL 组(P<0.05),以60mg/L GA作用更强。

与空白对照组比较,ox-LDL组细胞内ROS、MDA及NADPH氧化酶水平增加,NO含量及SOD活性降低,差异均有统计学意义(P<0.05);与ox-LDL组比较,GA30mg/L组、GA60mg/L组及VitE组细胞内ROS、MDA及NADPH氧化酶水平降低,NO含量及SOD活性增加,差异均有统计学意义(P<0.05),以60mg/L GA作用更强。

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Introduction of perovskites
The mechanism for the oxygen-ion conduction of this material is
not currently fully understood（some ralated factors）. For an example, the increase of oxygen vacancies usually enhances oxide
(3)
Results and discussion 1. Lattice constants and ionic conductivities
Results and discussion
The calculated MSDs of each ion are shown in Fig. 3
Results and discussion
Results and discussion
All of the calculated data for the lattice constant, the ionic conductivity and the activation energy in this study is in reasonable agreement with previously reported experimental
(1)
where N is the total number of ions and r(t) is the position of an ion i at the time t.
Some related simulation method
MSD has a relation to the diffusion coefﬁcient as the Einstein relation MSD(t)=6Dt (2) where t is the time and D the diffusion coef ﬁ cient. The ionic conductivity was obtained from the diffusion coefﬁcient accordingto the Nernste-Einstein equation
ion conductivity.However, the ionic conductivity of (BaxLa1-x)InO3 -0.5x
decreases with increasing numbers of oxygen vacancies, which has been not been fully understood through pure experimental approaches. Meanwhile, molecular dynamics simulations employing a vacancy diffusion model have been developed for analyzing such experimental results and have been applied to the study of the conductivity of oxygen by perovskite oxides Therefore, in this study, we explored the open question of oxide ion conduction in Ba-doped LaInO3 perovskite by employing a molecular dynamics simulation with a vacancy diffusion model.
respectively. This means that the bottlenecks have small critical radii when a Ba ion is located within it. This also
implies that oxide ion conductivity is affected by the local
Some related simulation method
According to previous studies, (BaxLa1-x)InO3 -0.5x has a cubic structure between x=0.4 and x=0.8. Hence, the amount of Ba dopant used for the calculation was in the range from 0.4 to 0.8. To derive the ionic conductivity, the mean square displacement(MSD) of oxide ion was calculated according to
((BaxLa1-x)InO3 -0.5x).The highest ionic conductivity of this
material was obtained in the region where the material exists as a cubic phase in the composition range from x=0.4 to x=0.5.
Introduction of perovskites
It is well known that A-site cation doped LaBO3
perovskites (B=Al, Ga, Sc, In and rare-earth ions) are oxide
ion conductors. Among these materials, Ba-doped LaInO3
pathway. 22 types of oxide ion migrations are available in Ba-doped LaInO3. The number of oxygen site pairs, Np, and the number of oxide ions migrating between the oxygen sites pair, Nm, were obtained as the average values for the 6 conﬁgurations with different ionic distributions.The diffusion frequencies per pair of oxygen
Results and discussion
Results and discussion
Results and discussion
The critical radius of the bottleneck is determined by the local distribution of the A-site cation species, Ba and La ions.
distribution of A-site cations.
Results and discussion
Table 3 shows the oxygen migration statistics which was
analyzed with the oxygen site pair and the migration
Fig. 4 shows an Arrhenius plot of the ionic conductivity obtained from eqs (1)-(3), with experimental data in the composition range from x=0.4 to x=0.5, where (BaxLa1-x)InO3 -0.5x is present in the form of a cubic phase .
data, indicating that our simulation methods can be
successfully used to reproduce the realistic diffusion of oxide
ions and can be used to examine the mechanism responsible
For example, in the La0.6Ba0.4InO2.8 at 900 ℃, the critical
radii of the∆LaLaIn, ∆ LaBaIn and ∆ BaBaIn bottlenecks
were calculated to be1.072 A, 0.964 A and 0.868Байду номын сангаасA,
Journal of Power Sources 222 (2013) 282e287
Oxide ion diffusion in Ba-doped LaInO3
perovskite: A molecular dynamics study
Dae-Seop Byeon
Huang xiaojun
Contents
Introduction of perovskites
Various dopants can alter the properties of the material, conferring a sufﬁciently high oxide ion conductivity that permits it to be applied to an electrolyte for solid oxide fuel cells (SOFC), electrolysers, oxygen pumps and amperometric oxygen monitors.
1 2
3 4
Introduction of perovskites Some related simulation method Results and discussion Conclusions