简介：通过室内实验，对比研究了四种保水剂的吸水、保水性能。测试吸水倍率、吸水速率、保水能力及有效持续性等指标，采用评分法对四种保水剂进行综合评价。结果表明：保水剂的吸水倍率与所吸溶液的性质有很大关系。4种保水剂在去离子水中的吸水倍率最高，随着溶液中离子浓度的增大吸水倍率逐渐减小。保水剂颗粒大小对吸水速率有较大影响，对其他指标影响均不大；4种保水剂均具有较强的反复吸水能力。综合分析认为，4种保水剂中，吸水保水性能最优的保水剂为40保水剂，其成分为聚丙烯酸盐和聚丙烯酰胺共聚体。其次为3“保水剂，再次为1^#保水剂，最差的是20保水剂。

简介：ＥＬＥＣＴＲＯＮ　ＴＲＡＮＳＦＥＲ　ＢＥＴＷＥＥＮ　Ｅｕ３＋　ＡＮＤ　Ｃｅ３＋　ＩＮ　ＳｒＭｇＦ４　ＭＡＴＲＩＸＥＬＥＣＴＲＯＮＴＲＡＮＳＦＥＲＢＥＴＷＥＥＮＥｕ３＋ＡＮＤＣｅ３＋ＩＮＳｒＭｇＦ４ＭＡＴＲＩＸ￥ＹｉｎｇＷＵ；Ｃｈ...

简介：Lophenol,cholest-4α-methyl-7-en-3β-ol(1),obtainedfromDracaenacochinchinensis(Lour.)S.C.Chen,wasstructurallymodified.Itwasacetylatedtoprotect3β-hydroxylgroup,andthenoxidisedbyseleniumdioxideinaceticacidtogivecholest-4a-methyl-8-en-3β,Ta-dioldiacetate(3).Thiscompound3isunstableinchloroformsolutionorwhenheatedandeasilyconvertedtoadienecompound,cholest-4a-methyl-7,14-dien-3β-olacetate(4).Thestructuresof3and4wereelucidatedbymeansofIR,^1HNMR,^13CNMRandMS,andtheabsoluteconfigurationof3wasestablishedbyX-raycrystallography.Thepropertyof3wasalsodiscussedinthispaper.Both3and4arenewcompoundsandwerereportedforthefirsttime.

简介：3-(2-Hydroxyphenyl)-6-(4-nitrophenyl)-7H-1,2,4-triazolo[3,4-b][1,3,4]thiadiazine,C16H11N5O3S,waspreparedbythecyclizationof3-(2-hydroxyphenyl)-4-amino-5-mercapto-1,2,4-triazolewith2-bromo-4-nitroacetophenone.Thecompoundwascharacterizedbymeansofelementalanalysis,IR,1HNMR,13CNMR,massspectrometry,andX-raydiffraction.ThecompoundcrystallizesinamonoclinicsystemwithspacegroupCc,a=2.1853(4)nm,b=2.1192(5)nm,c=1.3526(3)nm,β=95.21(2)°,V=6.238(2)nm3,Dcalcd.=1.505Mg/m3,Z=16,F(000)=2916,R1=0.0501,wR2=0.0427.Acomparisonbetweenthecrystalstructuresof1,2,4-triazolo[3,4-b][1,3,4]thiadiazineand1,2,4-triazolo[3,4-b][1,3,4]thiadiazolewasmadeinthestructuralview.Atwo-dimensionalnetworkisformedbyhydrogenbondsandπ-πstackinginteractions.

简介：Ionothermalsynthesiswasusedtoprepareanovelaminoacidcontaininghybridzincophosphatemonomer,[Zn(HPO4)(H2PO4)][C6H10N3O2](denotedasZnPO-CJ58).Theinorganicframeworkof[Zn(HPO4)(H2PO4)]·[C6H10N3O2]consistsof4-memberedringsformedbyZnO3OHisandPO2(OH)2tetrahedra.TheHPO4andaminoacidmoietieshangontheZncenter.Suchaframeworkisstabilizedbyextensivemultipointhydrogenbondsinvolvingthephosphateunitsandhistidinemoleculestoformapseudo-3Dsupramolecularstructure.ItisnoteworthythatZnPO-CJ58isthefirstzincphosphateclusterwithaminoacidactingastheligand.Itexhibitsphotoluminescenceexcitedatawavelengthof220nm.Interestingly,ZnPO-CJ58cantransformintoalayeredstructure(C6H10N3O2)Zn2·(HPO4)(PO4)·H2O(ZnPO-CJ36)throughfurtherreactingwithwaterorzincacetatedihydrateinwaterat85℃for1h.Thisworkwillbehelpfulforthesynthesisofcrystallineinorganic-organichybridmaterialswithbiofunctionalmolecules.

简介：标题化合物C22H29N3O3以简单易得的试剂为原料,在乙醇溶剂中,微波辐射下经两步多组分反应合成得到.其结构通过单晶X射线衍射法确定,晶体属三斜晶系,空间群P-1,相对分子质量Mr=383.48,晶胞参数a=1.14770（12）nm,b=2.0657（2）nm,c=1.00780（12）nm,V=2.1841（4）nm3,Z=4,晶胞密度Dc=1.166mg/m3,吸收系数μ=0.078mm-1,单胞中电子的数目F（000）=824.晶体结构用直接法解出,经全矩阵最小二乘法对原子参数进行修正,最终的偏离因子为R1=0.0709,wR2=0.1405.在晶体结构中新形成的噌啉环为近似于共平面结构,而其中的哒嗪环则为船式构象.

简介：2-Phenyl-1,2,3-triazole-4-formylhydrazine(2)waspreparedbyhydrazinolysisofthecorrespondingester1.Reactionof2withCS2/KOHgavetheoxadiazolederivatives(3)whichvia,Mannichreactionwithdifferentdialkylaminesfurnished3-N,N-dialkylderivatives(4a-c).Also,condensationof2withappropriatearomaticacidinPOCl3yieldedoxadiazolederivatives(5a-c),orwithaldehydesandketonesaffordedhydrazones(6a-c).Cyclizationof(6a-c)withaceticanhydridegavethedesireddihydroxadiazolederivatives(7a-c).Ontheotherhand,reactionofdithiocarbazate(8)withhydrazinehydrategavethecorrespondingtriazolederivative(9)whichontreatmentwithcarboxylicacidsinrefluxingPOCl3yieldeds-triazole[3,4-b]-1,3,4-thiadiazolederivatives(10a-b).ThestructuresofalltheabovecompoundswereconfirmedbymeansofIR,1HNMR,MSandelementalanalysis.

简介：

简介：Asimpleeffectivesynthesisofbis(dihydropyrimidinone-4-yl)benzenederivatives,usingboricacidascatalyst,fromisophthalicaldehydeorterephthalicaldehyde,1,3-dicarbonylcompoundsandureaorthioureainglacialaceticacidwasdescribed.AstheexpansionoftheclassicalBiginellireaction,thismethodhastheadvantageofexcellentyields83%-94%andshortreactiontime0.5-1.5h.

简介：在亲水性Fe3O4磁流体中，以甲基丙烯酸（MAA）为单体，N，N’-亚甲基双丙烯酰胺（MBA）为交联剂，采用光化学方法在水溶液体系中首先合成磁性聚甲基丙烯酸（PMAA）微球，进而在60℃下PMAA与稀土元素Dy离子反应合成具有荧光特性的磁性微球（FMPMs）．运用振动样品磁强计（VSM），光子相关光谱仪，傅立叶变换红外光谱仪（FTIR）和热重-差热分析（TG-DTA）分别对微球的磁性能，平均水合粒径,化学组成和表面形貌进行了检测．结果表明，荧光磁性高分子微球有超顺磁性，呈很好的球形，表面含有丰富的稀土羧酸盐．

简介：包含4-tert-butyltoluene一半的一系列新奇聚酰胺3a3d，用phosphorylationpolycondensation技术被准备。英尺红外和1HNMR技术被用来调查3a3d的化学结构。结果证实他们完全为3a3d同意了建议结构。3a3d有固有的粘性从0.71～1.67dL

简介：

简介：Afacileandconvenientsynthesismethodhasbeendevelopedforsubstitutedquinoxalinesand2H-benzo[b][1,4]oxazinesfromthereactionsofα-bromoketoneswithbenzene-1,2-diamineand2-aminophenol,respectively,whichwerecatalyzedbytetrabutylammoniumbromide(TBAB)inaqueousbasicmedia.

简介：介绍了在软Ｘ－射线显微术研究领域中有重要应用的Ｓｉ３Ｎ４薄膜窗口的实验室制作方法，并形成一套独特制备工艺，Ｓｉ３Ｎ４薄膜窗口的研制成功推动了我国软Ｘ射线显微术研究的发展。

简介：采用离子色谱法同时测定磷酸钠中的F-、C1-、SO4^2-、NO3-4种阴离子，对淋洗液等色谱条件进行了优化，4种离子的分离度好，检测灵敏度高，被测离子的浓度在一定范围内与色谱峰面积呈良好的线性关系，相关系数r〉0．999，4种离子测定结果相对标准偏差小于3％（n=9），加标回收率为80％-110％。方法简便快速，测定结果准确，可满足检测要求。

简介：

简介：

简介：ThespinelferritesMnFe2O4nanowiresweresynthesizedbyhydrothermalroute,porousMnFe2O4andnanoparticlesmorphologiesweresynthesizedbysol-gelmethodwitheggwhite.Thestructures,morphologies,magneticpropertiesandadsorptionpropertiesoftheseobtainedferriteswithdifferentmorphologieswerestudiedcontrastively.Resultsshowthattheobtainedsamplesexhibitferromagneticproperties.Thisrealizesconvenientmagneticseparationfromsolutionwhentheyareusedinthetreatmentoforganicdyeswastewater.However,thecontrastivestudiesshowthatthesaturationmagnetizations(Ms)ofMnFe2O4withdifferentmorphologiesaredifferentandtheMsfollowstheorder:Ms(porous)

简介：WiththedecreaseofpHvaluefrom8.45to–1.0,theUV-Visabsorptionandfluorescentspectraof1,2-bis(4-pyridyl)ethylene(BPE)tookonthesamechangingtrendatfourdifferentsuccessivepHstages:8.45―7.20,7.20―5.62,5.62―2.60,and2.60―-1.0,namely,nochange,decrease,increase,anddecreaseagain.Amongthese,inarangeof7.20―5.62,thefluorescencewavelengthblueshiftedfrom418to359nm,buttheUV-Visabsorptionwavelength,incontrast,redshiftedfrom285to298nm.ThefluorescenceintensityofBPEhadadropeventoquenchuponadeclineinthepHvaluefrom2.60to–1.0probablyowingtoitscation-πinteractiontoreducetheπelectronclouddensityofBPE.Twodissociationconstants,pKa1(4.30±0.01)andpKa2(5.65±0.04),wereobtainedbasedonfluorescencedata.ThechangesoffluorescencespectraindicatethatBPEhas'off-on-off'switchbehavior.ThefluorescentspectraofBPEwerenearlyindependentonthepresenceofα-andβ-cyclodextrins.

简介：实验选取与抗炎免疫密切相关的磷酸二酯酶4为靶点,应用超滤液质联用技术和酶体外活性抑制实验筛选并鉴定了葛根中抑制磷酸二酯酶4活性成分.实验结果表明葛根提取物具有抑制磷酸二酯酶4的作用,IC50值为0.04g/L.葛根素抑制磷酸二酯酶4作用最强,其次为大豆苷和大豆苷元,IC50值分别为52.79,71.54和122.17μmol/L.超滤液质联用实验筛选结果与体外活性实验一致.3′-羟基葛根素和3′-甲氧基葛根素在2个实验中均没有抑制磷酸二酯酶4的作用.