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1.
AStudyofSynthesis,ImmobilizationandCatalyticCapabilityofMetaloporphyrin*WANGXing-qiao**,GAOShuang,CAChang-shengYULian-xiang,G...  相似文献   

2.
The reaction of benzaldehyde, -nitro ketone, and cyanothioacetamide in the presence of morpholine has given the novel 3,4-trans-2-R-5-cyano-2-hydroxy-3-nitro-4-phenyl-1,2,3,4-tetrahydropyridine-6-thiolates. It was found that the reaction occurs via the formation of 1-amino-2-cyano-4-nitro-5-oxo-3-phenyl-1,2-pentene-1-thiolate. In the case of -nitroacetophenone, 3,4-trans-4,5-trans-5-cyano-2-hydroxy-3-nitro-2,4-diphenylhexahydropyridine-6(1H)-thione was also obtained. The use of -nitroesters in place of the nitro ketones in the reaction leads to morpholinium 2-aryl-1-carbethoxy-3-cyano-1-nitro-3-thiocarbamoylpropyl-1-ates as the single product.  相似文献   

3.
StudyofPreparationandCharacteristicsofPyridoxalated PolyhemoglobinLiangShuguang;TongMingrong;PanJilunandYuYaoting(Institutefo...  相似文献   

4.
Using two techniques of thermogravimetry and differential scanning calorimetry under O2 gas atmosphere from 25 to 600°C, the thermal behavior of laboratory-produced compound lead(IV) oxide α-PbO2 was investigated. The identity of products at different stages were confirmed by XRD technique. Both techniques produced similar results supporting the same decomposition stages for the compound. Three distinct energy changes were observed, namely, two endothermic and one exothermic in DSC. The amount of ΔH for each peak is also reported.  相似文献   

5.
6.
《结构化学》2020,39(9):1633-1638
We report here a cocrystal with artesunate as the active pharmaceutical ingredient(API) and a pharmaceutical intermediate 4,4?-bipyridine as the cocrystal former(CCF). The analysis of single-crystal X-ray diffraction demonstrates that the eutectic structural unit consists of two artesunate molecules and one 4,4?-bipyridine molecule with their ratio to be 2:1. The carboxyl group on artesunate acts as a donor, and the acceptor is N on 4,4?-bipyridine, forming an O–H···N hydrogen bond. The appearance of new diffraction peaks in the X-ray powder diffraction pattern also indicates the formation of new phases. The PXRD results indicated a pure phase for the synthesized sample. The cocrystal is slightly soluble in water. Antimicrobial activities showed that the cocrystal displayed effective inhibition of different bacteria.  相似文献   

7.
Introduction[Si,C ,O ,O]systemhasattractedmuchattentioninthefieldsofchemistryandmaterials1 3becauseofthefollow ingseveralcauses .First,theinterestisthepotentialimpor tanceininterstellarspace .Heretofore ,SiC ,SiOandCOhavebeendetectedwithintheinterstellarmediumformanyyears,butno [Si,C ,O ,O]isomerswereobservedinthenebulae .FormanySi containingsystemshavebeenstudiedexperimentallyandtheoretically ,4 8andinviewofthepossibleexistenceofthe [Si,C ,O ,O]radicalininterstellarspace ,weselectthe…  相似文献   

8.
The electrochemical oxidation of diphenylamine in acetonitrile produces an adherent uniform polymer film which exhibits mutiple colour variation(yellow-green-blue) in a wide range of potential scan. The polymerization mechanism and the structure of the polymer were studied by cyclic voltammetry, FT-IR and in situ ESR. The results indicate that the electrochemical polymerization of diphenylamine belongs to a cationic radical polymerization process. During electrolysis, only oligomers were initialy produced, then polymer film was formed on the electrode surface. The electropolymerization performs via the 4,4' C-C phenyl-phenyl coupling mechanism.  相似文献   

9.
A detailed singlet potential energy surface(PES) of [Si,C,O,O] system including a van der Waals (vdW) comples SiO……CO2,eight isomers,and twelve transiton states is investigated by MP2 and QCISD(T) (single-point)methods.At the final QCISD(T)/6-311 G(2df)//MP2/6-311G(d) level with zero-point energy included,the complex SiO……CO is found to be thermodynamically and kinetically the most stable species.Although eight ismoers are located as local energy minima,they are rather unstable toward isomerization to the dissociation fragments or comples.For the reaction of silocon atoms with carbon dioxide,two competitive reaction channels are found,and the primary pathway,which leads to the products of SiO and CO fragments,is the direct oxygen-abstraction process from carbon dioxide by silicon atom with a41.16 kJ/mol reaction barrier height.Our predications are in good agreement with previous experimental and theoretical studies.  相似文献   

10.
IntroductionBoththestudiesonthelow-dimensionmaterialsofmodifiedPbTiO3andpurePbTiO3werecarriedoutsynchronously,theauthorshopedtostrengthenthephysicochemicalproper-tiesofthematerialsinsomerespectsbymeansofchangingdesignmodificationscheme.Amongthenumero…  相似文献   

11.
This paper reports a study on the preparation of Ag-clad Au colloidal monolayer films by a combination of colloid self-assembly and liquid phase microwave high-pressure technique. Firstly, monodisperse Au nanoparticles prepared by microwave heating method were assembled onto a quartz slide. Then, these Au colloidal particles on the quartz surface acted as seeds for growing the Ag-clad Au composite particulate films. The obtained particulate films were characterized by UV-Vis spectra and atomic force microscopy. It was found that the thickness of the shell and thus the size of particles in the composite colloidal films could be controlled by deposition of Ag on the preformed Au colloidal particle film in the microwave reaction system, and such films significantly increased the surface-enhanced Raman scattering enhancement (SERS) ability compared with Au colloidal particle films. Their strong enhancement ability may mainly stem from relatively large particle consisting of Ag cladding as well as effective coupling among particles in the Ag-clad Au particle ftlms.  相似文献   

12.
Summary. The electronic and geometry structures of all enol and diketoforms of 3-oxopropionyl halogenides were investigated at the B3LYP/3-21G** level of theory. The comparative study of their energies revealed that the enol forms of the compounds are more stable than cis- and trans-diketones. All cis-diketones (except Cl-containing one) have one imaginary frequency in their vibration spectra, i.e. they do not correspond to local or global minima on the potential hypersurface. The keto–enol transformations enolcis-diketone and enoltrans-diketone for a certain triad of tautomers/isomers pass through one transition state or in other words, the two conversions have one common maximum on the energy hypersurface. The energy barriers of the keto–enol conversions found for isolated molecules are quite high. Only for the enoldiketone conversions in solution the energy barriers are slightly reduced.  相似文献   

13.
夏其英  肖鹤鸣  居学海  贡雪东 《中国化学》2004,22(11):1245-1249
Introduction The organoaluminum azide compounds have been widely used in many fields. These compounds are used as the azidating agents,1-3 and the energetic materials which are always used in national defence industry and in space technology, especially to generate thin films of AlN in various chemical vapor deposition (CVD) sys-tems.4-6 Aluminum nitride has useful properties for coatings, especially for optical or optoelectronic devices, acoustic wave devices and electronic microcircuits.7 …  相似文献   

14.
SupportedbyNaturalScienceFoundationforInstitutionsofHigherLearningofAnhui.mcnoGi~driwasfoundtobeastiInulantforplangIowthinl926.wthwaswidefyedinagriuled~andmedtalSCenee.InndmppeadVanCeSonthedeVlOPmenofgib~havbeenInadIl].HoweVerthereisno~onhaaPPljcatitOanalghtalcheInistIyuPtonow.The~formulaof~llinisasfollows-Becauseofthe~ketoneinnim~e,bellinpoSSeSSeSatmp.ShenNdsetal.l'edghammoniUInInO~forthe~etricedonofgib~edinSPtalustothinkthatsom~lyacidsSUchasInol~acidsofboc,PhOSPhOnJS,sili…  相似文献   

15.
IntroductionSnake-cageresin,alsoca1ledsnake-cagepolyelectrolyte['],isaspecialkindofamphotericresin.ItwasfirstinvestigatedbyHatchM.J.etal.in1957[z].Thetypicalandusefulsnake-cageresinisRetardation11A-8(l1A-8inthecon-text)manufacturedbyDowChemicalCoI,TD.Itissynthesizedbypolymerizingacrylicacidinsidethenetworkofastrongbasicanionexchangeresinwith8%crosslinking.Thus,theresinconsistsofacrosslinkedpolymermatrix,cage,andalinearpolymer,socalledsnake,whichisphysicallytrappedinsidethecage.Thecagepol…  相似文献   

16.
Morerecently,thesynthesisofnewdyeswithlargeupconvertedfluorescencebecomesthefocusoftheresearchandhasopenedupamyriadofapplications.Theapplicationsincludetwo-photoninducedlasing',two-photonopticalpowerlimiting',threedimensionalopticaldatastorage',andphotodynamictherapy'.Nevertheless,thistechniquehasneverreacheditsfullpotentialduetothelackofdyeswhichexhibithighupconvertedfluorescentilltensity.ThisrepoFtdescribesthesynthesisandpropertiesoftwo-photoninducedfluorescencedyeswhicharespecificallydesign…  相似文献   

17.
Russian Journal of General Chemistry - Clusters (Ih)-(Cd, Hg, Yb)@(Pb12, Sn12), (C5v)-(Ag, Au)@BiPb11, (C5v)-Ag@SbSn11, (D5d)(Ni, Pd, Pt)@Bi2Pb10, (D5d)-Pd@Sb2Sn10, (C3v)-(Pb12, Sn12)·(Pb, Sr,...  相似文献   

18.
Cationic polyaspartamides including poly-α,β-[N'-(2-aminoethyl)-L-aspartamide] (PAEA), poly-α,β-[N'-(4- aminobutyl)-L-aspartamide] (PABA), poly-α,β-[N'-(6-aminohexyl)-L-aspartamide] (PAHA), poly-α,β-[N'-(5-amino- 3-azapentyl)-L-aspartamide] (PAAPA) and poly-α,β-[N'-(8-amino-3,6-diazaoctyl)-L-aspartamide] (PADAOA) were synthesized from polysuccinimide. Their properties were evaluated by ^1H NMR, IR, GPC, fluorescence measurement and in vitro cytotoxicity assays. The molecular weights per primary amine charge group of PAEA(1) (Mn= 2229), PAAPA and PADAOA are 212, 279, and 226. Polyaspartamides including PAEA(1), PAAPA, PADAOA and low molecular weight PAHA are markedly less toxic than poly(ethyleneimine) and poly(L-lysine), however, PABA and higher molecular weight PAHA are slightly less toxic than poly(L-lysine). Cell cytotoxicity of PAHA was seen to decrease with increasing molecular weight of PAHA, due to water solubility reduction. The negatively charged plasmid DNA has been found to be completely neutralized and complexed by the cationic polyaspartamides at an N/P ratio of 5 : 1 to 10 : 1, forming self-assembled polyplexes via ionic interactions. These polyaspartamide/DNA complexes possess stable zeta potentials and mean particle diameters of about 180 nm for PAEA (1)/DNA and PAAPA/DNA complexes and 280 nm for PADAOA/DNA complexes.  相似文献   

19.
The methanolic extract from a Chinese endemic Chrysanthemum plant, Dendranthema indicum var. aromaticum, was found to show high antifeeding activity against Pieris brassicae L., and by bioassay-guided separation, the active component, B-ring-homo-tonghaosu, 2-(2‘,4‘-hexadiynylidene)-1,6-dioxaspiro-[4,5]-dec-3-ene (2) was isolated. Its structure was elucidated by comparing its spectroscopic data with those of 2 reported in the literatures. Furthermore new convenient total synthesis methods of B-ring-homo-tonghaosu were also developed to confirm its structure and make its further application in crop protection available. In addition, extensive comparison of spectroscopic data showed that the structure of compound 21 reported in literature should be revised to 2.  相似文献   

20.
The synthesis of crystalline complexes of trivalent lanthanides and americium with N,N-dimethylacetamide (DMAA) and PW12O40 3–anions was described. Their IR and electronic absorption spectra were studied. The structure of the neodymium complex [Nd(DMAA)6PW12O40] was determined using X-ray diffraction analysis. The thermal behavior of the lanthanide complexes was studied. In the 300–400°C temperature interval, even in air, intramolecular partial reduction of the anion occurs to form products which can be characterized as tungsten bronzes.  相似文献   

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