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1.
以液体定量~(31)P核磁共振波谱(~(31)P NMR)为主要表征手段,通过建立水中加盐促溶的高聚合度聚磷酸铵(APP)水溶液的制备方法,研究不同溶解温度、测试温度及NMR参数等对APP聚合度的影响,建立了~(31)P NMR准确表征APP的聚合度及其链结构的方法.研究结果表明,于36℃在水中加盐溶解APP,26℃下进行~(31)P NMR测试,既保证了APP溶液良好的溶解性,又在水溶液制备和~(31)P NMR测试过程中不引起APP降解,测得的APP聚合度稳定、准确.利用液体~(31)P NMR确定了不同温度下APP盐水溶液中端基磷和中间磷弛豫时间(T_1),发现T_1与温度呈线性关系,弛豫时间参数(D_1)的设置影响APP聚合度结果,D_1设置不满足磷所需的T_1时,APP的聚合度结果偏大.~(31)P NMR表征APP链结构结果显示,APP的端基磷存在3种化学环境,而溶液离子强度和温度会影响3种端基磷的化学位移;APP的中间磷中含有H~+.此外,提出了中国化工行业标准HG/T 2770-2008中APP高聚合度测定存在的问题.  相似文献   

2.
Cd(Ⅱ)和ATP的结合位点的NMR研究   总被引:1,自引:0,他引:1  
用NMR方法研究了金属镉离子在ATP(嘌呤三磷酸腺苷)上的配位点.测量了不同pH值时由于Cd2+的存在而引起的1H,15N及31P的化学位移和31P-31P中的偶合常数的变化以及由ATP的存在所引起的113Cd的化学位移的变化.结果表明,在pH>4.5的条件下,ATP主要以磷酸根和N7同时对Cd2+配位;在pH值2.5~4.5的条件下,ATP主要以磷酸根和N1同时对Cd2+配位,还存在少量的磷酸根和N7同时配位的模式;而在酸性非常强的条件下(pH<2.5),ATP不再与Cd2+相互作用。  相似文献   

3.
以2-乙氧基乙胺和3-氯-1-丙醇等为起始原料, 经7步反应, 制备了N,N-二[二(3-甲氧基丙基)膦基乙基]-2-乙氧基乙胺(PNP5)盐酸盐, 其中关键步骤是后两步. PNP5盐酸盐的结构和组成通过IR, 1H NMR, 13C NMR, 31P NMR, MS和元素分析等方法确认.  相似文献   

4.
以吲哚并[2,1-b]喹唑啉-6,12-二酮(色胺酮)及三苯基膦乙酸乙酯(酯基磷叶立德)为原料,在二氯甲烷中反应2 h,经Wittig/Michael串联反应,以高达99%的收率一步合成了15个含有吲哚并喹唑啉骨架的磷叶立德衍生物。其代表产物的结构经X-ray单晶衍射进行确证,化合物结构经1H NMR, 13C NMR, 31P NMR, 19F NMR和HR-MS(ESI-TOF)表征。  相似文献   

5.
通过将抗病毒药物核苷(3'-叠氮-2',3'-二脱氧胸苷AZT或2',3'-二脱氢-2',3'-二脱氧胸苷d4T)与三氯化磷反应, 然后在不同的醇解试剂作用下, 一锅法合成得到6个含长链烷基的核苷氢亚磷酸二酯衍生物, 并采用31P NMR, 1H NMR, 13C NMR和ESI-MS对其结构进行了表征.  相似文献   

6.
31P(1H)NMR和1HNMR研究表明,当NaOH加入到水溶性铑膦配合物HRh(CO)·(TPPTS)3[TPPTS:P(m-C6H4SO3Na)3]后,可观察到有少量的OTPPTS[OTPPTS:O=P(m-C6H4SO3Na)3]出现,但配合物的特征谱峰即使在高浓度的NaOH存在下也基本保持不变,表明NaOH对配合物分子结构的影响较小;当吡啶加入到HRh(CO)(TPPTS)3中,31P(1H)NMR谱图中出现游离配体TPPTS的31P谱峰及若干结构未知的新水溶性配合物的31P谱峰,表明吡啶分子将与配合物分子中的配体TPPTS发生配体交换反应.在HRh(CO)(TPPTS)3中分别加入一定量的HCl,HNO3,H2SO4和H3PO4等无机酸时,随着酸量的增加,配合物的31P物种含量逐渐下降,而OTPPTS量明显上升,直至配合物31P物种完全消失;高浓度乙酸对配合物结构的影响与上述无机酸类似.HRh(CO)(TPPTS)3的1-己烯氢甲酰化催化反应结果表明,碱存在下可获得较高的正异构醛比值,但催化活性降低;酸存在下所得产物正异构醛比值相对较低且呈淡黄色.  相似文献   

7.
报道了一种合成甲基对硫磷-D6的新方法。以三氯硫磷、氘代甲醇和对硝基苯酚为起始原料,经三次酯化反应合成了目标产物甲基对硫磷-D6,总收率47.6%,其结构经1H NMR、 13C NMR、 31P NMR和HR-MS(ESI)确证。  相似文献   

8.
高分辨NMR研究金属盐对水溶性铑膦配合物分子结构的影响   总被引:1,自引:0,他引:1  
用高分辨NMR研究了NaCl、NiSO4、CuSO4、Fe2(SO4)3和Cr2(SO4)3对水溶性铑膦配合物HRh(CO)(TPPTS)3[TPPTS;P(m-C6H4SO3Na)3]分子结构的影响.31P(1H)和1HNMR谱显示,于室温下在HRh(CO)(TPPTS)3中加入的NaCl或NiSO4对配合物的特征31P(1H)和1HNMR谱峰无明显影响;当加入CuSO4后,配合物的Rh-H质子峰强度弱化明显,进而消失,且原配合物的特征磷谱峰强度减弱,新生成的磷物种谱峰逐渐成为磷谱的主要物种.当加入Fe2(SO4)3或Cr2(SO4)3后,三价金属离子的强顺磁性使NMR灵敏度下降,谱峰宽化,该2种盐均易与水溶性铑膦配合物产生强烈的相互作用,易使配合物特征谱峰消失.实验结果表明,上述金属盐对配合物结构破坏性大小的顺序为;Fe2(SO4)3>Cr2(SO4)3>CuSO4》NiSO4~NaCl.  相似文献   

9.
用Hagihara脱氢卤代法合成了三种新的9,9-二(十六烷基)芴基二聚炔铂(d8)、金和汞(d10)化合物反式- [Pt(Ph)(PEt3)2C≡CRC≡CPt(Ph)(PEt3)2, [(PPh3)AuC≡CRC≡CAu(PPh3)]和[MeHgC≡CRC≡CHgMe] [R=9,9-二(十六烷基)芴基]. 用1H NMR, 13C NMR, 31P NMR, FT-IR, FAB-MS, UV-Vis, 荧光和磷光光谱对其进行了表征. 结果表明, 体系中的铂、金和汞产生的重原子效应可以有效地促进单线激发态S1与三线激发态T1的系间跃迁, 使标题化合物产生有机三线态发光.  相似文献   

10.
用三氯化铝催化六氯三聚膦腈开环聚合制得线性聚二氯膦腈(PDCP), 通过PDCP磷原子上的亲核取代反应, 合成了新的水溶性高分子聚[(甲氧基乙氧基乙氧基)1.0(乙氧基吡咯烷酮)1.0]膦腈(P3), 用31P NMR, 1H NMR, 13C NMR和IR对其结构进行了确证, 用DSC测定了其玻璃化转变温度Tg和熔融温度Tm, 用蒸汽压渗透法(VPO)测定了其数均分子量. 改进了聚二(乙氧基吡咯烷酮)膦腈(P2)的合成方法. 体外降解实验表明, P3具有和P2类似的pH响应性降解行为, 降解速率在pH=5.0时最快, 而在pH=7.4和8.0时较慢. P3在所测试的3个pH缓冲溶液中均比P2降解慢. 用31P NMR、薄层色谱(TLC)和滴定法对降解产物进行了检测, 初步推断了P3在不同pH介质中的水解机理, 其在pH=5.0的缓冲溶液中的降解, 除侧链断裂外, 聚膦腈的骨架也裂解; 而在pH=7.4和8.0时的降解仅为侧链的断裂. 用噻唑蓝(MTT)比色法进行的体外细胞毒性评价实验表明, P3及其在pH=5.0的缓冲溶液中降解49 d后的产物均对细胞表现出了很好的生物相容性, 而且其降解产物在浓度为800 μg/mL时还表现出一定的促进细胞增殖作用.  相似文献   

11.
Three novel flame retardants containing both phosphorus and silicon elements in their structures,including[(1,1,3,3- tetramethyl-1,3-disiloxanediyl)di-2,1-ethanediyl]bis(diphenylphosphine oxide)(FR-1),[(2,4,6,8-tetramethylcyclotetra-siloxane -2,4,6,8-tetrayl)tetra-2,1-ethanediyl]tetrakis[diphenylphosphine oxide](FR-2) and 1,3,5,7,9,11,13,15-octakis(di-phenylphosphine oxide-2,1-ethanediyl)pentacyclo[9.5.1.13,9.l5,15.17,13]octasiloxane(FR-3) were synthesized by a convenient pathway from the reaction of diphenylphosphine oxide(DPPO) and vinyl-terminated siloxanes under the catalysis of triethylborane. The chemical structures of the target compounds were confirmed by nuclear magnetic resonance(1H NMR,13C NMR,29Si NMR and 31P NMR),matrix-assisted laser desorption/ionization time-of-flight mass spectrometry(MALDI-TOF-MS) and Fourier transform infrared(FT IR) measurements.Thermogravimetric analysis(TGA) results indicated that the new flame retardants possessed good thermal stability both in nitrogen and in air.FR-3 containing polyhedral oligosilsesquioxanes(POSS) moiety exhibited the best thermal properties with a 10%weight loss temperature>400℃ and a residual weight ratio>39%at 700℃ .  相似文献   

12.
采用不同的方法制备了一系列Ga改性的ZSM-5分子筛催化剂, 通过固体核磁共振波谱(ssNMR)技术对催化剂的结构和酸性进行了表征, 并考察了其催化丙烷芳构化的性能. 结合71Ga NMR、 吸附三甲基磷(TMP)探针分子的一维31P 和二维(2D)1H-31P HETCOR NMR实验, 发现物理混合法制备的Ga2O3/ZSM-5样品只含有具有较弱Lewis酸性的Ga2O3物种, 浸渍法制备的Ga/ZSM-5-ox和浸渍后还原再氧化法制备的Ga/ZSM-5-redo 2种样品上主要以高分散的氧化镓和阳离子Ga物种为主, 而离子交换法制备的Ga/ZSM-5-IE样品上Ga主要以阳离子Ga物种的形式存在, 高分散的氧化镓和阳离子Ga物种都具有更强的Lewis酸性. Ga/ZSM-5分子筛催化丙烷芳构化反应的结果表明, Ga物种与酸性明显影响催化剂的芳构化性能, 丙烷的转化率和芳烃的选择性顺序为 Ga/ZSM-5-IE>Ga/ZSM-5-redox>Ga/ZSM-5-ox>Ga2O3/ZSM-5>H-ZSM-5. 2D 1H-31P HETCOR NMR实验结果表明, Ga/ZSM-5催化剂上产生的Br?nsted酸和Lewis酸(阳离子以及高分散Ga物种)的协同作用提高了分子筛的催化反应活性.  相似文献   

13.
以磷钨酸(H3PW12O40)和氯化铯(CsCl)为原料, 两亲型三嵌段共聚物F127为模板剂, 按不同的Cs/P比制备了一系列介孔磷钨酸铯盐(CsxH3-xPW12O40, m-CsPW). 通过X射线粉末衍射(XRD)、 场发射扫描电子显微镜(FESEM)、 场发射透射电子显微镜(FETEM)、 N2吸附-脱附测试和小角X射线散射(SAXS)等手段对所得样品进行了表征. 结果表明, 样品是由纳米微晶组装而成的晶态介孔材料. 以三甲基膦为探针分子, 通过31P魔角旋转固体核磁共振波谱(31P MAS NMR)测定了样品酸处理前后的酸密度和酸强度. 以5,7-二羟基-4-甲基香豆素的Pechmann缩合反应为模型反应, 考察了样品的酸性质与催化活性之间的关系.  相似文献   

14.
The mobility of inorganic phosphate (P) attached to solid humic acid (HA) and fulvic acid (FA) via a metal “anchor” was investigated by 31P NMR spectroscopy. The peak width of the 31P resonance was monitored as an indicator of the degree of attachment of the element to the humic matrix. The concept was demonstrated by contrasting peak widths of thoroughly dry M–HA–P complexes with those that had been allowed to absorb different amounts of moisture. It was shown that the presence of moisture, which enhances the mobility of P, results in a significant reduction of chemical shift peak width. The work was extended to comparisons between dry systems with and without metal anchors; systems with anchors consisting of different metals; systems comprising different humates and fulvates; and systems with different size fractions of a humate. It was shown that both the type of humate/fulvate, and the metal anchor used lead to different degrees of mobility within the humic matrix. It was also found that the effect of metal addition on 31P peak width is greater with fulvates and smaller HA fractions than with the larger HA components.  相似文献   

15.
Stannoles bearing dialkylboryl groups in 3-position react with 1-phospha-1-alkynes P≡C---tBu (1) and P≡C---CH2tBu (2) by [4 + 2] cycloaddition and elimination of stannylene to give phosphabenzenes in high yield. The stannylenes oligomerise to give [R12Sn]n with n ≥ 7 (R --- Me, Et, -(CH2)5− or, in the case of R1 = tBu, react with the stannole itself. All phosphabenzenes are characterized by their consistent sets of NMR data. The absolute signs of the coupling constants nJ(31P, 1H), nJ(31P, 13C), 2J(31P, 29Si) and 2J(119Sn, 31P) were determined by appropriate ID and 2D NMR experiments.  相似文献   

16.
采用生物质原料腰果酚和9,10-二氢-9-氧杂-10-膦杂菲-10-氧化物(DOPO)为原料, 合成了一种磷杂菲改性腰果酚多元醇(P-Cardanol-Polyol), 并利用核磁共振氢谱和磷谱对其结构进行了表征. 利用P-Cardanol-Polyol对聚氨酯硬泡(RPUF)进行阻燃改性, 得到一系列阻燃聚氨酯硬泡. 考察了P-Cardanol-Polyol的用量对阻燃聚氨酯硬泡的形貌、 密度、 热导率、 压缩性能、 热稳定性以及阻燃性能的影响. 研究结果表明, P-Cardanol-Polyol对聚氨酯硬泡的密度影响可以忽略不计; 随着P-Cardanol-Polyol的加入, 阻燃聚氨酯硬泡的平均孔径逐渐减小, 热导率也逐渐降低. 未改性聚氨酯硬泡的最大热释放速率和总放热量分别为390 kW/m2和31.9 MJ/m2, 阻燃聚氨酯硬泡则降低至340 kW/m2和24.6 MJ/m2. 此外, 阻燃聚氨酯硬泡的压缩强度比未改性聚氨酯硬泡提升了约13%. 炭层分析结果表明, P-Cardanol-Polyol能够促进聚氨酯硬泡形成连续致密且具有良好抗热氧化性能的炭层, 有利于减少燃烧过程中可燃性气体的逸出, 从而提升阻燃性能.  相似文献   

17.
Using phosphorus pentachloride as a substrate, a new carbacyclamidophosphate, N,N″-bis (2,6-dimethylmorpholino), N″-dichloroacetyl phosphoric triamide (1) has been synthesized and characterized by 1H, 31P and 13C NMR, IR spectroscopy and elemental analysis. Due to the presence of methyl disubstituted morpholine rings and the dichloroacetamide group, several conformers can be considered for this molecule. The 31P{1H} NMR spectra for the isomeric mixture of synthesized compound showed four signals with the ratio 67.1; 19.0; 12.2; 1.7, which indicates four independent conformers. The 1H NMR spectra confirmed these results. The conformational space and the molecular geometry of the molecule in the gaseous phase have been studied using the B3LYP method of approximation, with 6-31G and 6-311++G** basis sets.  相似文献   

18.
Titrimetric methods and 31P NMR spectrometry have been compared for the determination of hypophosphite (H2PO2) and phosphite (HPO·-3) in both alkaline and acid solutions used in the electroless deposition of nickel-phosphorus alloys. It has been shown that reproducible and reliable redox titrimetric methods can be used to follow the charges in concentration of both species with time during the plating process. In addition, measurements of the phosphorus in the nickel deposit by conversion to phosphate in acidic solution and use of flow-injection analysis has enabled satisfactory phosphorus mass-balance in the system to be achieved.  相似文献   

19.
Min Peng  Qun Chen   《Chemical physics letters》2008,456(4-6):189-192
Solid-state 1H wide-line and 31P magic angle spinning NMR were applied to a series of PEI(polyethylenimine)/DNA complexes. The experimental results revealed that the higher the nitrogen/phosphorus (N/P) molar ratio is, the more phosphorus atoms of DNA are engaged in the electrostatic interaction with PEI. 1H spin–diffusion experiments manifested that the aggregation degree of DNA in the complexes decreases greatly when N/P ratio increases from 0.5 to 3 and changes only slightly with further increase of N/P ratio, indicating that DNA disperses in the matrix of PEI on the molecular level at higher N/P ratio.  相似文献   

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