TiSiW_(12)O_(40)/TiO_2催化合成苯甲酸戊酯

首次报道了以固载杂多酸盐TiSiW12 O4 0 /TiO2 为多相催化剂 ,对以苯甲酸和正戊醇为原料合成苯甲酸戊酯的反应条件进行了研究 ,实验表明 :TiSiW12 O4 0 /TiO2 是合成苯甲酸戊酯的良好催化剂 ,最佳反应条件为 :醇酸摩尔比为 4∶1,催化剂用量为反应物料总量的 1 5 % ,反应时间为 2 5h。上述条件下 ,苯甲酸戊酯的产率可达 96 7%。     

TiSiW_(12)O_(40)/TiO_2催化合成葡萄糖酯的研究

以固载杂多酸盐TiSiW12 O4 0 /TiO2 为多相催化剂 ,对以乙酸酐、丙酸、丁酸、异丁酸和葡萄糖为原料合成葡萄糖酯的反应条件进行了研究。实验表明 :TiSiW12 O4 0 /TiO2 是合成葡萄糖酯的良好催化剂 ,最佳反应条件为 :n(糖 )∶n(酸 ) =1∶6 ,催化剂用量为反应物料总质量的 2 0 % ,反应时间为 2h。上述条件下 ,葡萄糖五乙酸酯的产率为 88 7% ,葡萄糖五丙酸酯的产率为 84 5 % ,葡萄糖五丁酸酯的产率为 85 4% ,葡萄糖五异丁酸酯的产率为 86 4%。     

TiSiW_(12)O_(40)/TiO_2催化合成丁酸异戊酯

以固载杂多酸盐TiSiW12 O4 0 /TiO2 为多相催化剂 ,通过正丁酸和异戊醇反应合成了丁酸异戊酯 ,并探讨了诸因素对酯化率的影响。实验表明 :TiSiW12 O4 0 /TiO2 具有良好的催化活性 ,醇酸物质的量比为 1 3∶1,催化剂用量为反应物料总量的 1 5 % ,反应时间 1 0h ,反应温度 12 0℃～ 130℃ ,酯化率可达 95 7%     

TiSiW_(12)O_(40)/TiO_2催化合成氯乙酸正戊酯

首次以固载杂多酸盐TiSiW12 O4 0 /TiO2 为多相催化剂 ,通过氯乙酸和正戊醇反应 ,合成了氯乙酸正戊酯 ,并探讨了诸因素对产率的影响 ,实验表明 ,TiSiW12 O4 0 /TiO2 具有良好的催化活性 ,当醇酸物质的量比为1 3∶1,催化剂用量为反应物料总量的 1 5 % ,反应时间 1 0h ,反应温度 10 8℃～ 12 6℃时 ,氯乙酸正戊酯的产率可达 78 0 4%。     

TiSiW12O40/TiO2催化合成苯甲酸异戊酯

首次报道了以固载杂多酸盐TiSiW12O40/TiO2为多相催化剂,对以苯甲酸和异戊醇为原料合成苯甲酸异戊酯的反应条件进行了研究。实验表明：TiSiW12O40/TiO2是合成苯甲酸异戊酯的良好催化剂,最佳反应条件为：醇酸摩尔比为4:1,催化剂用量为反应物料总量的2.5%,反应时间2.5h。上述条件下,苯甲酸异戊酯的产率可达83.3% 。     

TiSiW12O40/TiO2催化合成葡萄糖酯的研究

以固载杂多酸盐TiSiW12O40/TiO2为多相催化剂,对以乙酸酐、丙酸、丁酸、异丁酸和葡萄糖为原料合成葡萄糖酯的反应条件进行了研究.实验表明TiSiW12O40/TiO2是合成葡萄糖酯的良好催化剂,最佳反应条件为n(糖)∶n(酸)=1∶6,催化剂用量为反应物料总质量的2.0%,反应时间为2h.上述条件下,葡萄糖五乙酸酯的产率为88.7%,葡萄糖五丙酸酯的产率为84.5%,葡萄糖五丁酸酯的产率为85.4%,葡萄糖五异丁酸酯的产率为86.4%.     

用环境友好催化剂合成氯乙酸丙酯的研究

首次报道了以固载杂多酸盐TiSiWl2 O4 0 /TiO2 为环境友好催化剂 ,通过氯乙酸和丙醇反应合成了氯乙酸丙酯 ,并探讨了诸因素对产率的影响。实验表明 :TiSiW12 O4 0 /TiO2 是合成氯乙酸丙酯的良好催化剂 ,最佳反应条件为 :醇酸物质的量比为 1 .4 :1 ,催化剂用量为反应物料总量的 2 .0 % ,反应时间 2 .0h,反应温度 95 -1 1 0℃。上述条件下 ,氯乙酸丙酯的产率可达 77.1 4 %。     

TiSiW12O40／TiO2催化合成苯甲酸戊酯

首次报道了以固载杂多酸盐TiSiW12O40/TiO2为多相催化剂,对以苯甲酸和正戊醇为原料合成苯甲酸戊酯的反应条件进行了研究,实验表明：TiSiW12O40/TiO2是合成苯甲酸戊酯的良好催化剂,最佳反应投机倒把为：醇酸摩尔比为4：1,催化剂用量为反应物料总量的1.5%,反应时间为2.5h。上述条件下,苯甲酸戊酸的产率可达96.7％。     

SO4^2-／TiO2-MoO3催化合成丁酸系列酯

以固体超强酸SO2 -4/TiO2 MoO3 为催化剂 ,通过正丁酸和正戊醇反应合成了丁酸正戊酯 ,探讨了诸因素对收率的影响。合成丁酸正戊酯的最优条件为醇酸物质的量比为 1 5∶1,催化剂用量为反应物料总质量的2 0 % ,反应时间 1 5h。在上述最优条件下 ,以乙醇、丙醇、丁醇、异戊醇和正丁酸为原料合成丁酸系列酯 ,丁酸乙酯的收率为 14 9% ,丁酸丙酯的收率为 4 5 4 % ,丁酸丁酯的收率为 6 8 0 % ,丁酸正戊酯的收率为 97 9% ,丁酸异戊酯的收率为 91 1%。实验表明 :SO2 -4/TiO2 MoO3 具有良好的催化活性。     

用环境友好催化剂合成肉桂酸异戊酯的研究

本文报道了以固载杂多酸盐TiSiW12 O40 /TiO2 为环境友好催化剂 ,对以肉桂酸和异戊醇为原料合成肉桂酸异戊酯的反应条件进行了研究。实验表明 :TiSiW12 O40 /TiO2 是合成肉桂酸异戊酯的良好催化剂 ,最佳反应条件为 :n(醇 )∶n(酸 ) =4∶1,催化剂用量为反应物料总质量的 2 .0 % ,反应时间 1.5h ,反应温度 10 6 - 114℃。上述条件下 ,肉桂酸异戊酯的收率可达 70 .6 %。     

(Ba_(1-α)Sr_α)_(4.8)(Sm_(0.7)La_(0.3))_(8.8)Ti_(18)O_(54)陶瓷的微波介电性能

采用固相合成法制备了(Ba(1-α)Srα)4.8(Sm0.7La0.3)8.8Ti18O54(α=0.1～0.5)系陶瓷,表征了该陶瓷的相组成和显微结构,测试了微波介电性能.结果表明:α=0.3时,(Ba(1-α)Srα)4.8(Sm0.7La0.3)8.8Ti18O54系陶瓷为单相的新钨青铜结构固溶体.α>0.3时,相继出现了第二相BaLa2Ti4O12和La0.66TiO2.993.随α的增加,(Ba(1-α)Srα)4.8(Sm0.7La0.3)8.8Ti18O54系陶瓷的相对介电常数(εr)先增大后有所波动,品质因数(Qf)先增大后减小,谐振频率温度系数(τf)单调减小.α=0.3时,在1 350℃烧结的陶瓷的微波介电性能最佳:εr=98.77,Qf=5184GHz,τf=10.9×10-6/℃,优于不掺杂的BaO-Sm2O3-TiO2陶瓷的.     

Ternary Complexes of cis-(NH(3))(2)PtCl(2) (cis-DDP) With Guanosine (guo), Cytidine (cyd) and the Aminoacids Glycine (gly), L-Alanine (ala), L-2-Aminobutyric Acid (2-aba), L-Norvaline (nval) and L-Norleucine (nleu)

The ternary complexes of formulae cis-[(NH(3))(2)Pt(nucl)(amac)]NO(3), where nucl = guo and cyd (guanosine and cytidine) and amac = the deprotonated aminoacids glycine (gly), L-alanine (ala), L-2-aminobutyric acid (2-aba), L-norvaline (nval) and L-norleucine (nleu), were prepared from the reactions of the binary chelated ones cis-[(NH(3))(2)Pt(nucl)(amac)]NO(3) with the nucleosides.They were characterized by (1)H, (13)C and (195)Pt NMR and IR spectra, together with elemental analysis and conductivity measurements. The aminoacids coordinate with Pt(II) in the ternary complexes with their terminal -NH(2) groups, guo through N(7) and cyd through N(3). Ligand-ligand hydrophobic interactions were also observed in the ternary complexes and were stronger with longer aliphatic chains of the aminoacids. The (3)E sugar conformation increased by 5-7% in the ternary systems, as compared to the free nucleosides, while the percentage of the gg conformation remained almost constant and the one of the anti conformation of the sugar increased also slightly. Finally, the h conformer around the C(alpha)-C(beta) bonds of the aminoacids reached a maximum in the binary systems and decreased again considerably in the ternary ones.     

Fe~(3 )、Zn~(2 )、Mn~(2 )、Cu~(2 )、Ca~(2 )、Mg~(2 )等离子共存体系中Ca~(2 )、Mg~(2 )的测定

叙述了Fe3 、Zn2 、Mn2 、Cu2 、Ca2 、Mg2 等离子共存体系中采用六次甲基四胺 -铜试剂沉淀除去Fe3 、Zn2 、Mn2 、Cu2 等干扰离子 ,用EDTA滴定钙镁的方法 ,该方法钙的回收率在 99.7%～ 10 0 .3 % ;镁的回收率在 10 0 .0 %～ 10 0 .4% ,标准偏差为 0 .0 2 2。     

Adhesion of calcium phosphate coatings on polyethylene (PE), polystyrene (PS), poly(tetrafluoroethylene) (PTFE), poly(dimethylsiloxane) (PDMS) and poly-L-lactic acid (PLLA)

Calcium phosphate (CaP) coatings can be applied to improve the biological performance of polymeric medical implants. For clinical applications, a strong adhesion of the coating to the polymeric substrate is important. Therefore, the adhesion of rf magnetron-sputter-deposited CaP coatings on five polymers was studied: polyethylene (PE), polystyrene (PS), poly(tetrafluoroethylene) (PTFE), poly-L-lactic acid (PLLA) and poly(dimethylsiloxane) (PDMS). To influence the adhesion, the interface was varied in six different ways, e. g. by a plasma or ion-beam pretreatment, or by using a Ti interlayer. The adhesion was determined by using scratch, tensile and 180^° bend tests. Especially the polymers PE and PS needed a bombardment by energetic particles prior to or during coating deposition, to enable the formation of chemical bonds between the coating and the polymer, which gave adhesion. On PLLA and PDMS, being oxygen containing polymers, it was easier to establish a strong interface. An overtreatment of the polymeric substrates gave worse adhesion, probably due to the formation of weak low molecular weight (LMW) layers on the polymer. On PTFE, the use of a Ti interlayer was necessary to prevent the PTFE from UV degradation during coating deposition, as this caused cohesive failure within the PTFE. The results showed that each polymer requires a different approach for obtaining optimal adhesion. The observed adhesion could often be explained in the terms of processes occurred during the pretreatment of the polymers or the deposition of the coating.     

(K_(0.485)Na_(0.485)Li_(0.03))NbO_3-Pb(Zr_(0.53)Ti_(0.47))O_3压电陶瓷的压电性能与微观结构

采用传统电子陶瓷制备技术和工业原料制备了新型(1-x)(K0.485Na0.485>Li0.03)NbO3-Pb(Zr0.53Ti0.47)O3少铅压电陶瓷,研究了该体系陶瓷的压电性能及微观结构.X射线衍射分析表明:在1250℃烧结3h的条件下,所有陶瓷样品都具有纯的钙钛矿结构和高致密性,并且在室温下形成了正交相和四方相共存的结构.x=0.75时,陶瓷的压电性能达到最佳:压电常数d33=363 pC/N,机电耦合系数kp=63%,相对介电常数εr=1 590,介质损耗tanδ=1.70%.     

EXTRACTION OF ACTINIDES(III), (IV), (V), (VI), AND LANTHANIDES(III) BY STRUCTURALLY TAILORED DIAMIDES

Eleven diamide extractants having the different backbones were synthesized and their extractability for lanthanides(III) and actinides(III), (IV), (V) and (VI) were measured and compared. The diamides investigated include (CH₂) _n ─(CONR₁,R₂)₂, (n = 0, 1, 2, 3), O─((CH₂) _n′─CONR₁,R₂)₂, S─((CH₂) _n″─CONR₁,R₂)₂, and SS─((CH₂)_n′″─CONR₁,R₂)₂, (n′, n″, n′″ = 1, 2). The diglycolamide introducing an ether oxygen into the main frame, O─(CH₂─CONR₁,R₂)₂, exhibited the highest extractability for An(III), (IV) and (VI), as compared with the other bidentate diamides. It is clear from the present results that the thiadiglycolamide, TDGA, which substitutes ether sulfur atom for oxygen in DGA molecule, also enhances the extraction of actinides. The lanthanide pattern, the distribution ratios versus the atomic number, by diglycolamide in HNO₃-n-dodecane system exhibited a gradual increase of distribution ratio with increase in the atomic number, the opposite trend to that obtained by the other diamides.     

Victrex® poly(ethersulfone) (PES) and Victrex® poly(etheretherketone) (PEEK)

Properties of two high performance engineering thermoplastics, amorphous polyethersulfone (PES) and semicrystalline polyetheretherketone (PEEK), are discussed. Both resins can be processed by conventional techniques, compounded with high performance fibers, and have high service temperature (up to 300°C). Due to the amorphous character PES can be dissolved and spray coated into metals.     

Ba(Zr_(0.055)Ti_(0.945))O_3含量对[(Na_(0.80)K_(0.16)Li_(0.04))_(0.5)Bi_(0.5)]TiO_3陶瓷性能的影响

系统研究(1-y)[(Na0.80K0.16Li0.04)0.5Bi0.5]TiO3-yBa(Zr0.055Ti0.945)O3无铅压电陶瓷,获得压电应变常数高达185pC/N的0.94[(Na0.80K0.16Li0.04)0.5Bi0.5]-TiO3-0.06Ba(Zr0.055Ti0.945)O3压电陶瓷。样品的晶体结构为三方相、四方相共存,处于准同型相界(morphotropic phase boundary,MPB)附近。该类陶瓷室温MPB的摩尔(下同)含量为0.050y0.065。样品y=0.060在40°左右的(003)、(021)双峰与46.5°左右的(002)、(200)双峰分裂最明显。随着Ba(Zr0.055Ti0.945)O3含量的增加,铁电相-反铁电相相变温度(θd)升高、反铁电相-顺电相相变温度(θm)降低;θd和θm的温差越来越小,材料的弛豫性逐渐降低。