Bi系高温超导体中2212相和2223相的性质分析

本文对 Bi 系中可能存在一种 T_c>100K 的2212相作了进一步的论证.化学分析显示普通的2212相中 Cu~(3+)含量为～10%,而2223相和 T_c>100K 的2212相中 Cu~(3+)的含量却大于30%.从 DTA-TG 实验中观察到普通2212相和2223相失去晶格氧的量为0.8%,而含 T_c>100K 的2212相的样品失去晶格氧的量为～2%,说明这种2212相受氧含量影响更大.文中还介绍了一种简易判断样品中是否存在2223相和普通2212相的经验方法.

VTMS与Bz、St及HFP等离子体共聚物的性能研究

采用外部电极电容耦合的RF辉光放电装置,对乙烯基三甲基硅烷(VTMS)与苯(Bz)、苯乙烯(St)以及六氟丙烯(HFP)进行共聚合。通过IR、TG、防潮试验、接触角测试研究了共聚物膜的性能。发现VTMS与Bz、St的共聚物膜具有优良的防潮性。

PROPERTIES OF BETA-CARBOXYETHYL-GERMANIUM SESQUIOXIDE AND INTERACTIONS OF IT WITH SOME SUBSTRATES

Three samples of β-carboxyethyl-germanium sesquioxide (Ge-132) have been prepared with different methods. Their IR, Raman, XPS, TG-DTA and FAB-MS spectra are quite different and indicate that they have different degree of polymerization and molecule structures. In the aqeous solution, all of them interaot strongly with fructose, but not with polypeptides such as GSH and GSSG. This faot may be important in understanding the bioactivity of Ge-132.

SURFACE CHARACTERIZATION OF COBALT TETRAPHENYLPORPHYRIN MODIFIED GLASSY CARBON ELECTRODE BY XPS

Surface structure of the glassy carbon surface modified with cobalt tetraphenyl-porphyrin (CoTPP) by thermal-treatment has been studied by XPS, DTA and TG. During the thermal treatment a bond can be formed between the glassy carbon surface and TPP. Therefore the stability of electrode for the catalysis of dioxygen reduction is improved. Upon thermal treatment at 600 degrees C, FWHM of Co(2p(2/2)) is broadened, the reason is due to overlapping of peaks of multiple states, the spin orbit separation between Co (2p(1/2)) and Co (2p(3/2)) increases to 15.5-16.3eV, which indicated a change from low spin divalent states, the kinetic energy of Co L3VV Auger line and Auger parameter also increase. These changes of central cobalt ion provide a suitable redox potential for Co(III)/Co(II) which is related to the activity for catalysis of dioxygen reduction.

乙烯基三甲基硅烷等离子体聚合物膜的结构与性能

采用外部电极电容耦合高频等离子体装置对乙烯基三甲基硅烷(VTMS)进行等离子体聚合。用IR、XPS、PGC/MS、X-ray、ESR和元素分析等方法对聚合物结构进行表征,并推断聚合反应历程。应用TG研究聚合物的热性能。通过X-ray证实聚合物为非晶结构。在无添加气体存在时聚合,XPS测试结果表明产物中有氧嵌入,且聚合物的C/Si比总的说来比单体的C/Si比低。TG的测试结果表明聚合物膜具有优良的热稳定性。

一种新型稀土苯甲酸铽配合物的合成、表征及其晶体结构

本文报道一种新型稀土苯甲酸配合物,[Tb(C_7H_5O_2)_3(C_7H_6O_2)(H_2O)]_2的合成。用元素分析、DTA、TG、DTG和IR光谱对其性质进行了表征,并测定了其晶体结构。晶体属三斜晶系,空间群为P1,Z=1。晶胞参数为:a=9.148(1),b=11.460(2),c=13.506(2)A;α=112.76(1),β=91.83(1),γ=91.99(1)°;V=1303.3(4)A~3。稀土离子形成九配位的单帽正方反棱柱型配合物,稍有崎变。

稀土-锌-还原谷胱甘肽三元配合物的合成及其性质

本文报道LnZn(OH)_2(GSH)_3·3H_2O(Ln=La,Pr,Nd)型三元配合物的合成及其IR,TG-DTA和XPS谱性质,讨论了配合物的结构。

用X射线光电子能谱对热处理的四苯基钴卟啉修饰电极的表面表征

本文用XPS、DTA和TG分析了四苯基钴卟啉化学修饰电极的热分解行为,它不同于四苯基铁卟啉.由XPS谱图揭示了四苯基钴卟啉与玻璃碳电极之间的相互作用,进而阐述了经热处理的四苯基钴卟啉化学修饰电极的表面结构与电催化稳定性的关系.从Co2p_3/2和2p_(1/2)能级的自旋分裂间距及其Shake-up伴峰,了解经热处理后的四苯基钴卟啉修饰电极中钴自旋态变化,并且从Co的L_3VV俄歇跃迁计算出Co的双电离能,其双电离能与电催化活性有一定关系。

INVESTIGATION OF MICROSTRUCTURE AT IRON TETRAPHENYLPORPHYRIN MODIFIED CLASSY CARBON ELECTRODE BY XPS

Microstructure of the glassy carbon surface modified with iron tetraphenyfporphyrin (FeTPP) by heat treatment has been studied by XPS,, DTA and TG. XPS spectra of Fe 2P_3\2 level in FeTPP and iron tetraphenylporphyriu/glassy carbon (FeTPP/GC) have shown that a bond can be formed between the glassy carbon surface and both the central metal iron ion and the macrocyclic, ligand, which loses its four phenyl groups during the beat treatment. The relationship between the surface mierostructure of FeTPP/GC and the...

钙钛石型催化剂La_(1-x)Sr_xFeO_(3-λ)的高分辨电子显微镜研究

钙钛石型复合氧化物的缺陷性质与其催化性能密切相关。在以前的报告中,作者用XRD、TG、Mssbauer谱等技术,研究了La_(1-x)Sr_xFeO_(3-λ)体系催化剂的晶体结构和缺陷性质以及它们与该体系催化剂在氨氧化反应中催化性能之间的关系,提出了在氧缺陷浓度较大的钙钛石中可能产生氧空位有序排列的结构.本文通过对上述体

铕和铽与3,4-呋喃二甲酸双核配合物的合成、表征及其晶体结构

本文首次合成了铕(Ⅲ)和铽(Ⅲ)与3,4-呋喃二甲酸配合物,研究了它们的IR、DTA、TG、DTG和荧光光谱等性质,并完成了单晶的晶体分析。结果表明,配合物为〔Ln·HL_2(H_2O)_2〕_2·2H_2O(Ln=Eu(Ⅲ),Tb(Ⅲ);H_2L=3,4-呋喃二甲酸),属单斜晶系,P2/c空间群,Z=2,晶胞参数对铕和铽配合物分别为α=10.842(1),10.801(4);b=8.725(2),8.664(2);c=16.366(4),16.308(6)A;β=93.50(1),93.67(3)°;V=1545.3(5),1523.0(8)A~3。

聚苯醚的溴化及其对富氧性能的影响

利用亲电反应及自由基反应分别对聚苯醚进行了不同程度的溴化。测定了不同温度下对O_2和N_2的透过率及相应的玻璃化转变温度和密度。发现苯环上的溴化有利于提高O_2和N_2的透过率,而选择性基本不变。甲基上的溴化大大提高了O_2、N_2的选择性,但透过率下降较多。苯环上溴含量与Tg呈很好的线性关系,密度亦随溴含量的增加而增加。透过率与温度的关系符合Arrhenius方程。溴化后的聚苯醚其透过活化能略有下降,并计算了溴化聚苯醚的摩尔自由体积和摩尔内聚能,发现其比值越大,O_2、N_2的透过率越大。

用X-光电子能谱对热处理的四苯基铁卟啉化学修饰电极的研究

本文用XPS、DTA、和TG分析了解四苯基铁卟啉和四苯基铁卟啉化学修饰电极的热分解行为。由XPS谱图揭示了玻璃炭与四苯基铁卟啉之间的相互作用,进而阐述了经热处理的四苯基铁卟啉化学修饰电极的表面结构与电催化稳定性的关系。从四苯基铁卟啉化学修饰电极的XPS价态谱发现Fe中心离子的3d电子在电极的电催化活性中的作用。

A transglutaminase from Chinese shrimp (Fenneropenaeus chinensis), full-length cDNA cloning, tissue localization and expression profile after challenge

Transglutaminase can catalyze the cross-linking reaction between soluble clotting protein molecules from the plasma for prevention of excess blood loss from a wound and obstructing micro-organisms from invading the wound in crustaceans. A novel transglutaminase (FcTG) gene was cloned from hemocytes of Chinese shrimp Fenneropenaeus chinensis by 3' and 5' rapid amplification of cDNA ends (RACE) PCR. The full-length cDNA consists of 2972 bp, encoding 757 amino acids with a calculated molecular mass of 84.96 kDa and a theoretical isoelectric point of 5.61. FcTG contains a typical transglutaminase-like homologue (TGc domain: E-value = 1.94e-38). Three catalytic sites (Cys-324, His-391 and Asp-414) are present in this domain. The deduced amino acid sequence of FcTG showed high identity with black tiger shrimp TG, kuruma shrimp TG and crayfish TG. Transcripts of FcTG mRNA were mainly detected in gill, lymphoid organ and hemocytes by RT-PCR. RNA in situ hybridization further confirmed that FcTG was constitutively expressed in hemocytes both in the circulatory system and lymphoid organ. The variation of mRNA transcription level in hemocytes and lymphoid organ following injection of killed bacteria or infection with white spot syndrome virus (WSSV) was quantified by RT-PCR. The up-regulated expression of FcTG in shrimp lymphoid organ following injection of bacteria indicates that it is inducible and might be associated with bacterial challenge. (c) 2006 Elsevier Ltd. All rights reserved.

Benthic foraminifera and bottom water evolution in the middle-southern Okinawa Trough during the last 18 ka

A piston sediment core E017 from the middle-southern Okinawa Trough was investigated. A preliminary study of the deep-water evolution since 18 cal. ka BP was performed based on the quantitative census data of benthic foraminiferal fauna, together with planktonic foraminiferal oxygen and carbon isotope, AMS(14)C dating, and the previous results achieved in the southern Okinawa Trough. The result shows that the benthic fauna was dominated by Bulimina aculeata (d'Orbigny), Uvigerina peregrina (Cushman), Hispid Uvigerina and Uvigerina dirupta (Todd) during the glaciation-deglaciation before 9.2 cal. ka BP, while Epistominella exigua (Brady), Pullenia bulloides (d'Orbigny), Cibicidoides hyalina (Hofker), Sphaeroidina bulloides (d'Orbigny) and Globocassidulina subglobosa (Brady) predominated the fauna in the post-glacial period after 9.2 cal. ka BP. The benthic foraminifera accumulation rate (BFAR), paleoproductivity estimates and benthic foraminiferal assemblage conformably indicate that surface water paleoproductivity and organic matter flux during the glaciation-deglaciation were higher than those of the post-glacial period in the middle-southern Okinawa Trough, and gradually enhanced from the southern to the central Okinawa Trough during the glaciation-deglaciation, which could be caused by the discrepancy of the terrigenous nutrients supply. High abundances of E exigua, an indicator of pulsed organic matter input, after 9.2 cal. ka. BP may indicate that the intensity of seasonally riverine pulsed flux during the post-glacial period was stronger than that of the glaciation-deglaciation period, and the seasonal influx in the central trough might be stronger than in the south. The temporal distributions of the typical species indicating bottom water oxygen content and ventilation condition show that the ventilation of the bottom water during the post-glacial period is more active than the glaciation-deglaciation, which reflects that the evolution of the intermediate and deep waters of the northwestern Pacific during the last glaciation has no evident influence on the deep-water of the middle-southern Okinawa Trough. Additionally, the variations in agglutinated benthic foraminiferal abundance and other carbonate dissolution proxies indicate that carbonate dissolution gradually increased since the last 18 ka in the Okinawa Trough and rapidly enhanced at 9.2 cal. ka BP. The modern shallow carbonate lysocline could form at 3 cal. ka BP.