3-叠氮甲基-3-甲基氧丁环的合成

以三羟甲基乙烷与碳酸二乙酯为原料,经环化反应合成了3-羟甲基-3-甲基氧丁环(HMM O)。在低温下,HMM O与对甲苯磺酰氯反应生成3-磺酸酯甲基-3-甲基氧丁环(M TM O)。M TM O和叠氮化钠发生叠氮化反应形成叠氮单体3-叠氮甲基-3-甲基氧丁环(AMM O)。三步反应收率分别为76%,96%,85%。用核磁、红外、元素分析和DSC表征了化合物的结构与性能。结构鉴定表明为目标化合物AMM O。     

3-溴甲基-3-甲基氧杂环丁烷的合成

以2,2-二溴甲基丙醇（BBMP）为初始原料,通过与碱发生关环反应生成3-溴甲基-3-甲基氧杂环丁烷（BrMMO）。讨论了碱的种类和用量对BBMP关环产率的影响以及反应体系中碱的浓度、反应温度和反应时间对合成BrMMO产率的影响。通过实验确定的最佳工艺条件为：BBMP与NaOH摩尔比为1.0∶1.1,NaOH醇溶液的质量分数为12%,反应温度为78℃,反应时间为4h时,BrMMO产率为65%。最终产品经元素分析、IR和1HNMR检测确定为BrMMO。该试验工艺简单,原料易得,且溶剂便于回收、污染小。     

3-溴甲基-3-甲基氧杂环丁烷的合成

以2,2-二溴甲基丙醇(BBMP)为初始原料,通过与碱发生关环反应生成3-溴甲基-3-甲基氧杂环丁烷(BrMMO).讨论了碱的种类和用量对BBMP关环产率的影响以及反应体系中碱的浓度、反应温度和反应时间对合成BrMMO产率的影响.通过实验确定的最佳工艺条件为:BBMP与NaOH摩尔比为1.0∶1.1,NaOH醇溶液的质量分数为12%,反应温度为78℃,反应时间为4 h时,BrMMO产率为65%.最终产品经元素分析、IR和1HNMR检测确定为BrMMO.该试验工艺简单,原料易得,且溶剂便于回收、污染小.     

2,2,3-三氯-3-苯基-3-(3-甲基苯甲酰基)丙腈的合成研究

以苯甲酰氯、四氯化碳、间甲基苯甲酰氰为原料,合成了标题化合物。重点考察了氰化过程中不同原料配比、反应温度、时间、溶剂和催化剂用量对收率的影响。实验结果表明,其最佳反应条件为:n(1,1,2-三氯-2-苯基乙烯)∶n(3-甲基苯甲酰氰)=1∶1.2,二氯甲烷为反应溶剂,3 mmol催化剂三乙胺,室温反应5 h,总收率达80.6%。     

甲胺铅碘钙钛矿物性及制备过程的分子模拟

应用分子动力学方法分析了甲胺铅碘晶体的结构特征与机械性质等相关物性,模拟了用蒸气沉积法在TiO₂基底上制备甲胺铅碘晶体的过程,探讨了生成的PbI₄^2-、PbI₅^3-和PbI₄^6-多面体的排布方式,结合周围CH₃NH₃⁺的分布筛选出满足结构要求的初生晶核,分析了前驱盐配比对甲胺铅碘初生晶核产量的影响。结果表明,在拉伸过程中,甲胺铅碘晶体经历弹性形变、塑性形变以及断裂三个阶段,拟合计算得到的弹性模量与实验值符合较好;大部分初生晶核以PbI₅^3-金字塔的结构存在。前驱盐配比对各系统中PbI_x多面体的总含量影响较小,但对其中排布有效的PbI_x结构以及初生晶核的产量影响较大,二者产量随着配比PbI₂∶CH₃NH₃I的增加而迅速减小,这一关系与研究者发现的实验现象相符。     

The Preparation and Crystal Structure of TlMnCl3, TlFeCl3, TlCoCl3 and TlNiCl3

The compounds TlMnCl₃, TlFeCl₃, TlCoCl₃ and TlNiCl₃ were prepared by heating T1C1 with the corresponding transition metal dichloride in an evacuated ampoule. Atomic positions were determined from powder photographs. All four compounds were found to be related to the perovskite type structure. TlMnCl₃ has a cubic structure, space group Pm3m, with a_o = 5.025 Å. The other three compounds are hexagonal, probable space group P6₃mc, with cell dimensions (in Å) a₀ = 6.976 and c₀ = 6.008 for the Fe compound, a₀ = 6.907 and c₀ = 5.981 for the Co compound and a₀ = 6.863 and c₀ = 5.881 for the Ni compound. The three hexagonal compounds are isomorphous. A measureable concentration of basal plane stacking faults was found to occur in TlFeCl₃ and also, to a lesser degree, in TlCoCl_3.     

Synthesis of some cobalt phthalocyanine-3 3 3 3-tetrasulphonamides and spectroscopic studies of their application to cellulosic fibres

The treatment of cobalt phthalocyanine-3, 3′, 3″, 3′″-tetrasulphonylchloride with different primary amines with different substituents has given eight novel cobalt phthalocyanine-3, 3′, 3″, 3′″-tetrasulphonamide compounds. The structure determination have been carried out using elemental analysis, molecular weight measurements and infra-red spectroscopy. Direct application of the new synthesised dyes to cotton and viscose fabrics at two different bath concentrations gave a range of percentage reflectances values in the visible region. The absorption maxima appeared in both cases in the range 670–680 nm.     

A broad theoretical investigation of R-3, R3c,and R-3c polymorphs of FeCrO3

The FeCrO₃ is a semiconductor founded in nature as a mineral. Such material exists in three different polymorphs whose properties have been few studied. Therefore, this work has performed a broad computational investigation based on a DFT approach aiming to present the nonreported properties; such as optoelectronic, photocatalytic, and phase stability under pressure. The results have indicated that the magnetic properties of the bulk for the three polymorphs present an antiferromagnetic overall ordering, being the residual magnetism experimentally reported caused by a morphology magnetization and not by a specific surface outcrop. Likewise, as electronic as photocatalytic properties predictions have suggested a bandgap in agreement to interest for applications in chemical processes; however, but the corundum phase has shown a significant photocatalytic activity due to charge carriers’ stability. In particular, the R3c phase of the FeCrO₃ has presented a multiferroic behavior, since a magnetoelectric coupling is expected. From all the results exposed in this work, we propose that the FeCrO₃ material can be suggested as a high-level candidate for technological purposes.     

2-羟基-3-甲基-3-丁烯腈的合成

通过甲醛与丙醛在盐酸二乙胺催化下缩合合成了 2 甲基丙烯醛 ,收率为 98%。反应操作分两阶段进行 ,第一阶段反应的pH值为 7,温度为 45℃ ;第二阶段反应在沸腾状态下进行 ,通过蒸馏得到产品。催化剂重复使用 4次对反应收率无显著影响。 2 甲基丙烯醛与氰化钠、盐酸在强烈搅拌 ,反应温度≤ 5℃下反应得 2 羟基 3 甲基 3 丁烯腈 ,收率 92 %。产品结构用1H NMR进行了确定。     

3-硝酸酯甲基-3-乙基氧杂环丁烷的合成及表征

以三羟甲基丙烷和碳酸二乙酯为原料,经环化、硝化两步反应合成出了3-硝酸酯甲基-3-乙基氧杂环丁烷(NIMEO),硝化反应的收率为75.1％,产品质量分数为98.8％.通过红外光谱、核磁共振氢谱及元素分析对产品的结构进行了表征,表明为目标化合物.考察了反应条件对产品收率的影响,确定了最佳的硝化条件:硝酸/醋酐为硝化剂,硝...     

3-芳基丙烯酸及其酯的合成

研究了以无水碳酸钾作催化剂 ,芳香醛与酸酐反应合成 3 芳基丙烯酸 ,用对甲苯磺酸催化酯化反应合成 3 芳基丙烯酸酯。产品结构经1HNMR、IR和元素分析证明与预期结构相符。     

Thermal analyses of poly(3-hydroxybutyrate), poly(3-hydroxybutyrate-co-3-hydroxyvalerate), and poly(3-hydroxybutyrate-co-3-hydroxyhexanoate)

Thermal analyses of poly(3-hydroxybutyrate) (PHB), poly(3-hydroxybutyrate-co-3-hydroxyvalerate) [P(HB–HV)], and poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) [P(HB–HHx)] were made with thermogravimetry and differential scanning calorimetry (DSC). In the thermal degradation of PHB, the onset of weight loss occurred at the temperature (°C) given by T_o = 0.75B + 311, where B represents the heating rate (°C/min). The temperature at which the weight-loss rate was at a maximum was T_p = 0.91B + 320, and the temperature at which degradation was completed was T_f = 1.00B + 325. In the thermal degradation of P(HB–HV) (70:30), T_o = 0.96B + 308, T_p = 0.99B + 320, and T_f = 1.09B + 325. In the thermal degradation of P(HB–HHx) (85:15), T_o = 1.11B + 305, T_p = 1.10B + 319, and T_f = 1.16B + 325. The derivative thermogravimetry curves of PHB, P(HB–HV), and P(HB–HHx) confirmed only one weight-loss step change. The incorporation of 30 mol % 3-hydroxyvalerate (HV) and 15 mol % 3-hydroxyhexanoate (HHx) components into the polyester increased the various thermal temperatures T_o, T_p, and T_f relative to those of PHB by 3–12°C (measured at B = 40°C/min). DSC measurements showed that the incorporation of HV and HHx decreased the melting temperature relative to that of PHB by 70°C. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 90–98, 2001     

Fluorescence spectra of Eu3 , Tb3 , Dy3 and Ho3 doped certain powder phosphors

This paper reports the photoluminescence spectral properties of Eu³⁺, Tb³⁺, Dy³⁺ and Ho³⁺ doped LaOX, YOX, (La, Gd)OX, and (La, Y)OX (X=F, Cl) powder phosphors. Under the UV-light these phosphors have exhibited bright reddish-orange, green, yellowish-blue and bluish-green colours. This papers also describes the effects of the halides change in the host material chosen specifically.     

Nd3＋、Er3＋、Gd3＋和La3＋对超氧化物歧化酶活性的影响

通过研究Nd3＋、Er3＋、Gd3＋和La3＋稀土离子对枯草芽孢杆菌在生长过程中所产的超氧化物歧化酶活性的影响,来探讨稀土可能会导致生物体发生氧化损伤。利用改良的邻苯三酚自氧化法测定超氧化物歧化酶活性。结果表明：4种稀土离子对其细胞中超氧化物歧化酶活性均有抑制作用,且Nd3＋的抑制作用较其它3种稀土离子要强,故一定浓度的稀土离子很有可能会导致生物体发生氧化损伤。4种稀土离子的浓度不同影响有所不同,总的来说,稀土离子的浓度越大,对枯草杆菌抗氧化的抑制作用越明显,损伤毒性作用越强。     

钾碳铵3KHCO3·NH4HCO3复合肥的生产

随着我国农业经济的发展，经济作物种植面积扩大，对无氯钾肥的需求量大幅度增长，全国年需无氯钾肥700kt左右。我国无氯钾肥主要是K2SO4和KNO3，在钾肥中所占比例很小，远不能满足经济作物的需求。我国北方大部分地区干旱缺水，对无氯钾肥需要量更大。目前，我国煤头     

Low thermal conductivity of SrTiO3−LaTiO3 and SrTiO3−SrNbO3 thermoelectric oxide solid solutions

Electron-doped SrTiO₃ has been attracting attention as oxide thermoelectric materials, which can convert wasted heat into electricity. The power factor of the electron-doped SrTiO₃, including SrTiO₃-LaTiO₃ and SrTiO₃-SrNbO₃ solid solutions, has been clarified. However, their thermal conductivity (κ) has not been clearly identified thus far. Only a high κ (>12 W m⁻¹ K⁻¹) has been assumed from the electron contribution based on Wiedemann–Franz law. Here, we show that the κ of the electron-doped SrTiO₃ is lower than the assumed κ, and its highest ZT exceeded 0.1 at room temperature. The κ slightly decreased with the carrier concentration (n) when n is below 4 × 10²¹ cm⁻³. In the case of SrTiO₃-SrNbO₃ solid solutions, an upturn in κ was observed when n exceeds 4 × 10²¹ cm⁻³ due to the contribution of conduction electron to the κ. On the other hand, κ decreased in the case of SrTiO₃-LaTiO₃ solid solutions probably due to the lattice distortion, which scatters both electrons and phonons. The highest ZT was 0.11 around n = 1 × 10²¹ cm⁻³. These findings would be useful for the future design of electron-doped SrTiO₃-based thermoelectric materials.     

Modelling of 3–3 piezocomposites for hydrophones

Abstract

Three-dimensional modelling of a 3-3 piezoelectric structure was carried out using finite element modelling software. Hydrostatic figures of merit were calculated for structures with increasing amounts of interconnecting porosity. In addition to using air as the second phase, polymer fillers were added to the three-dimensional model in order to observe the effect of polymer Young's modulus on the piezoelectric properties of the bulk material. Results show that increasing the porosity has the effect of improving the hydrostatic piezoelectric properties for applications such as low frequency hydrophones.     

Electric properties of polycrystalline PbCd1/3Nb2/3O3

Temperature dependence of dielectric permittivity and electric conductivity of polycrystalline PbCd_1/3Nb_2/3O₃ in the region of phase transition have been presented. Electric properties of polycrystalline PbCd_1/3Nb_2/3O₃ depend on frequency of the measuring field. In the region of para-ferroelectric phase transition a change of electric properties takes place.