立方晶型Sb2O3纳米晶的合成及光催化性能

采用沉淀法合成了立方晶型Sb2O3纳米晶,通过X射线衍射(XRD)、扫描电镜(SEM)、透射电镜(TEM)、紫外-可见漫反射光谱(UV-Vis DRS)和电子自旋共振谱(ESR)等对样品进行了详细的表征。以紫外光光催化降解甲基橙为反应模型评价了样品的光催化性能。结果表明:沉淀法合成的立方晶型Sb2O3纳米晶颗粒小,表现出良好的光催化性能。对立方晶型Sb2O3纳米晶光催化降解甲基橙的原因进行了探讨,并提出了降解甲基橙的反应机理。     

SnO2+Sb2O3中间层的制备条件对Ti/SnO2+Sb2O3/PbO2阳极性能的影响

二氧化铅;SnO2+Sb2O3中间层的制备条件对Ti/SnO2+Sb2O3/PbO2阳极性能的影响     

溶剂热法制备纳米晶Sb2O3

以 SbCl3为锑源,采用溶剂热法制备了纳米Sb2O3(1),其结构经XRD和SEM表征.溶剂的种类和体系 pH可以控制1的晶型及形貌.水作溶剂时,1为板状斜方晶型;乙醇作溶剂时,1为单一斜方晶型或立方和斜方混合晶型;用乙醇和乙二醇混合溶剂时,1为斜方晶型;用乙醇和异丙醇混合溶剂时1为单一立方晶型.     

Al_2O_3·3H_2O阻燃环氧树脂机理探讨

采用氧指数测定法与热重法研究了 Al2 O3 · 3H2 O对环氧树脂固化物的阻燃效果与机理 .结果表明 ,Al2 O3 · 3H2 O在热分解方面与树脂固化物有阻燃匹配性 ,并能以零级反应快速失去 2个结晶水分子 ,失水后形成的活性氧化铝促进了树脂固化物热解时转化成难燃物的能力 ,具有较高的阻燃效果 .     

十二烷基苯磺酸钠微乳体系制备纳米Fe2O3

十二烷基苯磺酸钠微乳体系制备纳米Fe2O3;微乳;电导率;萃取率;纳米Fe2O3     

丙烯酸改性卤锑阻燃PP的结晶形态

用双螺杆挤出机制备了丙烯酸改性Sb2O3/聚丙烯母料,并注塑成Sb2O3/DBDPO阻燃PP样条.用偏光显微镜和广角X射线研究了阻燃PP中PP的结晶形态.结果表明Sb2O3对PP结晶形态的影响不同于十溴联苯醚（DBDPO）的,根据球晶形态,Sb2O3对PP的异相成核作用比DBDPO的明显,虽然在Sb2O3/PP母料中无β球晶,但在DBDPO/PP和阻燃PP中存在β球晶.对于丙烯酸改性阻燃PP,PP的结晶形态取决于丙烯酸用量,随着丙烯酸用量增加,在高DCP用量条件下,容易形成β球晶.     

棒状Sb2S3-nafion纳米复合膜修饰玻碳电极的大肠杆菌DNA传感器

将棒状Sb2S3纳米粒子与Nafion聚合物在乙醇溶液中超声混合得到均匀的Sb2S3-Nafion纳米复合材料分散液。将该复合材料滴涂至玻碳电极(GCE)表面,得到稳定的Sb2S3-Nafion修饰电极。循环伏安和阻抗表征实验表明,由于Sb2S3的纳米尺寸效应及半导体效应,电极的电化学性能得到了极大的提高。采用PCl5为活化剂,将Nafion表面的磺酸基团酰氯化,再利用共价键合法将末端修饰氨基的大肠杆菌DNA特征序列固定到修饰电极表面,制备了一种新型的DNA电化学传感器。以亚甲基蓝(MB)为杂交指示剂,将制备的DNA电化学传感器应用于大肠杆菌基因目标序列检测,结果表明,该传感器对目标DNA具有较宽的动力学线性范围(1.0×10-12～1.0×10-7mol/L),检出限达到2.4×10-13mol/L。此外,选择性实验表明该传感器对互补序列、单碱基错配序列、三碱基错配序列和完全错配序列具有良好的识别能力。     

α-Fe_2O_3-TiO_2/SA复合半导体薄膜的制备及光催化性能的研究

应用sol gel法制备纳米α Fe2O3、TiO2及α Fe2O3 TiO2粉体,并以其作前驱体制得该纳米微粒与海藻酸钠的复合膜.由红外光谱(FT IR)、X 射线粉末衍射(XRD)、荧光光谱(PL)、透射电子显微镜(TEM)和循环伏安(I V)等物理化学方法表征、测定各复合薄膜的表面结构与催化活性.紫外 可见吸光光度法等研究结果表明,以杀菌紫外灯作光源,在纳米Fe2O3、TiO2及α Fe2O3 TiO2与海藻酸钠的复合膜悬浮液中,亚甲基蓝可被快速脱色降解,若于α Fe2O3中加入15%的TiO2,其α Fe2O3 TiO2复合晶体比单一的α Fe2O3或TiO2具有更高的光降解活性.     

选择性合成不同形貌的Sb2S3纳米结构应用于高性能的染料敏化太阳能电池（英文）

近几十年来,随着全球变暖和能源危机的日益严重,对取之不尽、用之不竭的清洁能源技术的需求越来越迫切.1991年Gratzel首次报道了染料敏化太阳能电池(DSSCs),它以低廉的价格、优异的理论功率转换效率(PCE)、环保、多色透明等优点而引起了研究者的关注.Sb2S3因其1.5-2.2 eV的间隙宽度被认为是最有前途的对电极材料之一.此外,Sb2S3是地球中含量丰富的无毒锑矿物的主要成分,还被广泛应用于太阳能转换材料、催化剂、光导探测器等领域.众所周知,石墨烯具有巨大的比表面积、显著的载流子迁移率和优异的热/化学稳定性,这使得提高电子转移效率和电催化活性成为可能.首先,采用改进的Hummers方法制备了氧化石墨烯纳米片;然后采用水热法通过改变Sb源以及实验pH值,合成了Sb2S3和Sb2S3@RGO样品.对样品进行X射线粉末衍射(XRD)、扫描电子显微镜镜(SEM)、投射电子显微镜(TEM)以及比表面积表征.结果表明,在Sb源不变的情况下,Sb2S3样品的形貌随pH值的变化而变化.以三乙酸锑为Sb源,在pH=3时,Sb2S3的形貌类似于一个完整的纳米棒结构;在pH值为6时,样品为不规则球体;当pH值为8时,纳米片结构开始出现;但当p H=10时,纳米片结构并不均匀.根据XRD分析,只有当pH值为3时,样品的衍射峰才与标准卡(JCPDS42-1393)的衍射峰一致.当以氯化锑作为锑源,样品的形貌由不规则的杆状(pH=3)转变为纳米球(pH=6),然后出现纳米片结构(pH=8).不同的是,当p H值为10时,纳米薄片形成均一的花状结构.XRD结果表明,除pH值为3外,样品的衍射峰与标准卡(JCPDS42-1393)的值吻合较好.结果表明,合成条件所需的Sb源和碱性环境是合成具有均匀花状结构的纳米片状Sb2S3所必不可少的.测得Sb2S3的比表面积约为41.72 m^2g^-1,平均孔径为31.08nm,Sb2S3@RGO的分别为44.53 m^2g^-1和22.65 nm.Sb2S3和Sb2S3@RGO复合材料均具有介孔结构,为内部电催化剂提供了广阔的通道,从而提高了对电极的催化能力,促进了电化学反应.将Sb2S3纳米花球和Sb2S3@RGO纳米薄片作为染料敏化太阳能电池的对电极进行了测试,由于石墨烯的引入,后者比前者具有更好的电催化性能.电化学实验结果表明,与Sb2S3,RGO,Pt作为对电极相比,制备的Sb2S3@RGO纳米薄片具有更好的催化活性、电荷转移能力和电化学稳定性,Sb2S3@RGO的功率转换效率达到8.17%,优于标准Pt对电极(7.75%).     

MC尼龙-纳米La2O3复合材料的制备及性能研究

用原位分散聚合法制备了一系列MC尼龙／纳米La2O3复合材料，研究了纳米La2O3用量对复合材料力学性能的影响，用SEM观察了La2O3粒子在MC尼龙基体中的分散情况，用XRD对复合材料的晶体结构进行了表征。SEM观察结果表明，当纳米La2O3用量小于1％时，纳米La2O3均匀分散于MC尼龙基体中，团聚情况很少，当纳米La2O3用量大于1％时，纳米La2O3开始团聚；XRD研究结果表明，纳米La2O3没有改变MC尼龙的结晶形态；力学性能的研究结果表明，随着纳米La2O3用量的增加，复合材料的拉伸强度、断裂伸长率、缺口冲击强度、弯曲强度和弯曲模量都呈先升后降的趋势，当纳米La2O3用量为0．5％时，复合材料的拉伸强度和断裂伸长率达到最大值，分别比MC尼龙提高17．9％和52．1％，当纳米La2O3的用量为1．0％时，复合材料的缺口冲击强度、弯曲强度和弯曲模量达到最大值，分别比MC尼龙基体提高36，6％．12．7％和16．3％。     

Darstellung,Kristallstrukturen, Schwingungsspektren und Normalkoordinatenanalyse von vier bindungsisomeren Trichlorotrirhodanoosmaten(IV)

Preparation, Crystal Structures, Vibrational Spectra, and Normal Coordinate Analysis of four Linkage Isomeric Trichlorotrirhodanoosmates(IV) By treatment of fac-[OsCl₃I₃]^2? with (SCN)₂ in dichloromethane the linkage isomers fac-[OsCl₃(NCS)₃]^2? ( 1 ), mer-[OsCl₃(NCS)₂^c(SCN)]^2? ( 2 ), mer-[OsCl₃(NCS)(SCN)₂^t]^2? ( 3 ), and mer-[OsCl₃(NCS)(SCN)₂^c]^2? ( 4 ) are formed which have been separated by ion exchange chromatography on diethylaminoethyl cellulose. X-Ray structure determinations have been performed on single crystals of fac-(Ph₄As)₂[OsCl₃(NCS)₃] (triclinic, space group P1 , a = 12.142(5), b = 13.233(5), c = 19.300(5) Å, α = 98.642(5)º, β = 100.509(5)º, γ = 112.514(5)º, Z = 2), mer-(Ph₄As)₂[OsCl₃(NCS)₂^c (SCN)] · acetone (triclinic, space group P1 , a = 11.707(5), b = 13.238(5), c = 19.048(5) Å, α = 75.960(5)º, β = 88.981(5)º, γ = 69.999(5)º, Z = 2), mer-(Ph₄As)₂[OsCl₃(NCS)(SCN)₂ ^t] (triclinic, space group P1, a = 10.6861(12), b = 11.6587(5), c = 12.5232(5) Å, α = 112.069(8)º, β = 95.052(8)º, γ = 92.559(7)º, Z = 1) and mer-(Ph₄As)₂[OsCl₃(NCS)(SCN)₂ ^c] · 2acetone (triclinic, space group P1 , a = 11.444(5), b = 14.661(5), c = 15.830(5) Å, α = 75.790(5)º, β = 80.273(5)º, γ = 75.205(5)º, Z = 2). The complex anions are completely ordered. The via N or S coordinated thiocyanate groups are located nearly direct above one of the cis-positioned Cl ligands with Os? N? C angles of 169.1º, 171.5º, 175.7º ( 1 ), 175.6º, 178.6º ( 2 ), 172º ( 3 ), and 173.1º ( 4 ) and Os? S? C angles of 106.2º ( 2 ), 106.1º, 106.6º ( 3 ), 105.1º, and 108.2º ( 4 ). Using the molecular parameters of the X-Ray determinations the low temperature (10 K) IR and Raman spectra of the (n-Bu₄N) salts of all four linkage isomers have been assigned by normal coordinate analyses based on a modified valence force field. The valence force constants are f_d(OsN) = 1.71 ( 1 ), 1.46 and 1.62 ( 2 ), 1.69 ( 3 ), and 1.61 ( 4 ), f_d(OsS) = 1.27 ( 2 ), 1.36 ( 3 ), 1.32, and 1.49 mdyn/Å ( 4 ). Taking into account increments of the trans influence a good agreement between observed and calculated frequencies is achieved.     

Darstellung,Kristallstrukturen, Schwingungsspektren und Normalkoordinatenanalyse von vier bindungsisomeren Tetrachlorodirhodanoosmaten(IV)

Preparation, Crystal Structures, Vibrational Spectra, and Normal Coordinate Analysis of Four Linkage Isomeric Tetrachlorodirhodanoosmates(IV) By treatment of cis- or trans-[OsCl₄I₂]^2? with (SCN)₂ in dichloromethane the linkage isomers cis-[OsCl₄(NCS)₂]^2? ( 1 ), trans-[OsCl₄(NCS)(SCN)]^2? ( 2 ), cis-[OsCl₄(NCS)(SCN)]^2? ( 3 ) and trans-[OsCl₄(SCN)₂]^2? ( 4 ) are formed which have been separated by ion exchange chromatography on diethylaminoethyl cellulose. The X-Ray structure determinations on single crystals of cis-(Ph₄As)₂[OsCl₄(NCS)₂] (triclinic, space group P1 , a = 10.019(5), b = 11.702(5), c = 21.922(5) Å, α = 83.602(5)°, β = 85.718(5)°, γ = 73.300(5)°, Z = 2), trans-(Ph₄As)₂[OsCl₄ · (NCS)(SCN)] (monoclinic, space group P2₁/c, a = 18.025(5), b = 11.445(5), c = 23.437(5) Å, β = 94.208(5)°, Z = 4), cis-(Ph₄As)₂[OsCl₄(NCS)(SCN)] (triclinic, space group P1 , a = 10.579(5), b = 11.682(5), c = 22.557(5) Å, α = 81.073(5)°, β = 85.807(5)°, γ = 87.677(5)°, Z = 2) and trans-(Ph₄As)₂ · [OsCl₄(SCN)₂] (triclinic, space group P1 , a = 10.615(5), b = 11.691(5), c = 11.907(5) Å, α = 111.314(5)°, β = 96.718(5)°, γ = 91.446(5)°, Z = 1) reveal the complete ordering of the complex anions. The via N or S coordinated thiocyanate groups are located nearly direct above one of the cis-positioned Cl ligands with Os? N? C angles of 171.2° and 174.3° ( 1 ), 162.3° ( 2 ), 172° ( 3 ) and Os? S? C angles of 108.3° ( 2 ), 105.7° ( 3 ) and 105.5° ( 4 ). Using the molecular parameters of the X-Ray determinations the low temperature (10 K) IR and Raman spectra of the (n-Bu₄N) salts of all four linkage isomers are assigned by normal coordinate analyses based on a modified valence force field. The valence force constants are f_d(OsN) = 1.59 ( 1 ), 1.67 ( 2 ), 1.60 ( 3 ) and f_d(OsS) = 1.27 ( 2 ), 1.31 ( 3 ) and 1.32 mdyn Å^?1 ( 4 ). Taking into account increments of the trans influence a good agreement between observed and calculated frequencies is achieved.     

Comparative Thermogravimetric Studies of Poly(ether-ketone/sulfone) Imides and Their Parent Polymers: I. Poly(ether-ketone/sulfone) ethylimide

Thermogravimetry (TG) was employed to study the thermal degradation kinetics of poly(etherketone/sulfone)ethylimide (PEK-IE and PES-IE). The corresponding decomposition activation energies and reaction orders were obtained and the comparison was made with their parent polymerspoly(ether-ketone/sulfone) with Cardo group (PEK-C and PES-C). The results show that the degradation activation energies of PEK-IE and PES-IE were lower than that of PEK-C and PES-C; and two stages of the degradation process were found for all the four polymers. For PEK-IE and PES-IE, the activation energies in the first decomposition stage are much lower than that in the second stage and the two stages can be taken as slow induction and fast degradation, whereas for PEK-C and PES-C the activation energies in the first decomposition stage are larger than that in the second stage, and the two stages can both be taken as two fast degradation stages. The decomposition mechanism of the two stages was also speculated.This revised version was published online in November 2005 with corrections to the Cover Date.     

Darstellung und Kristallstruktur von (n-Bu4N)3[Ir(NCS)(SCN)5]

Preparation and Crystal Structure of (n-Bu₄N)₃[Ir(NCS)(SCN)₅] The evaporated ethanolic extrakt of the reaction product of K₃[IrCl₆] and HNO₃, refluxed with an aqueous KSCN solution yields a mixture of the linkage isomers [Ir(NCS)_n(SCN)_6?-n]^3?, n = 0? 2, and small amounts of linkage isomeric chloropentarhodanoiridates(III), from which [Ir(NCS)(SCN)₅]^3? has been isolated by ion exchange chromatography on DEAE-cellulose. The X-Ray structure determination on a single crystal of (n-Bu₄N)₃[Ir(NCS)(SCN)₅] (monoclinic, space group P 2₁/a, a = 17.513(5), b = 32.607(5), c = 23.661(5) Å, β = 94.757(5)°, Z = 8) confirms the existance of a heteroleptic hexakis(thiocyanato(N)-thiocyanato(S))iridate(III) with an Ir? N distance of 2.03 Å and Ir? S bond lengths between 2.29 and 2.38 Å. The SCN groups with angles between 166 and 175° are nearly linear with Ir? S? C angles from 99.9 to 109.4°. The Ir? N? C angles of the two crystallographic independent anions are 166 and 174°.     

SYNTHESIS AND CHARACTERIZATION OF METAL COMPLEXES WITH AMPICILLIN

Abstract

The reaction, in water, of Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) ions with sodium ampicillinate at room temperature has allowed isolation of dimers with the following general formula [M(amp)Cl]₂ × nH₂O (n = 1.5?3.2). The complexes were characterized by elemental analyses, conductivity measurements, magnetic susceptibilities and spectroscopic methods (IR, Raman, EPR and UV-Visible). A dinuclear structure based on octahedrally coordinated metal ions is proposed.     

PMDA-BPDA-HAB聚苯并噁唑的合成及耐热性

PMDA-BPDA-HAB聚苯并噁唑的合成及耐热性;均苯四甲酸二酐;联苯四羧酸二酐;二羟基联苯胺;聚酰亚胺;聚苯并噁唑;耐热性     

Thermal Degradation of Poly(ε-caprolactone), Poly(L-lactic acid) and their Blends with Poly(3-hydroxy-butyrate) Studied by TGA/FT-IR Spectroscopy

Summary: The thermal degradation behavior of poly(ε-caprolactone) (PCL) and poly(L-lactic acid) (PLA) have been studied in different environment. It was found that these polymers undergo completely different degradation processes in nitrogen and oxygen atmosphere. In oxygen environment PCL and PLA mainly decompose to CO₂, CO, water and short-chain acids. In nitrogen atmosphere PCL releases 5-hexenioc acid, CO₂, CO and ε-caprolactone, whereas PLA decomposes to acetaldehyde, CO₂, CO and lactide. The polymer blends of poly(3-hydroxybutyrate) (PHB) with PCL and PLA decompose similar to the individual homopolymers with crotonic acid as the initial decomposition product of PHB.     

Energy relationship and the polarization of C_(60) cage in the endohedral complexes (X@C_(60))

In this paper, we carry out the calculation on the system (X@C60)(X=Li, Na, K, Kb, Cs; F, Cl, Br, I), where the position of X changes along 5 typical symmetry directions. For the calculation of quantum chemistry we use EHMO/ASED method, for the calculation of molecular mechanics we use Buckingham potential (exp-6-1) function, and for the calculation of thermo-chemical cycle we use individually isolating the processes such as the structure variation, charge transfer and charge distribution, and their interactions etc. The calculation results show that (1) In the region of radius r≈0.2 nm of the Ceo cage, the potential field is nearly spherical; (2) Except for Li and Na, the systems are the most stable with minimum energies at the center of C60 cage. For Li and Na, the systems are the most stable with minimum energies at r≈0.16 nm and r≈0.13 nm, respectively. In view of the interactive region of chemical bonds, the interactions between X and the C60 cage do not belong to the classical chemical bonds; (     

铜在3%NaCl溶液中腐蚀行为的光电化学研究

Cu以其优异的导电性、导热性和易加工性广泛用于工农业生产中．自然Cu的腐蚀和防腐成为人们很关注的问题．人们已经注意到，Cl-对Cu的腐蚀有影响，并进行过一些研究．但目前使用光电化学方法研究这一问题的文章尚不多见，特别是利用测量开路光电压及其瞬态波形这一现场的、无损的、灵敏的监测方法研究户对Cu电极腐蚀全过程的文章尚未见到．本文正是利用如上方法及XPS，AES方法，研究了Cl-对Cu电极腐蚀的全过程，取得了一些有意义的结果．1实验方法Cu电极用99．99％（质量分数）的Cu制成，面积约为39mm2；电极底部由Cu导线焊接引出，…     

On the morphological behavior of ABC miktoarm stars containing poly(cis 1,4-isoprene), poly(styrene), and poly(2-vinylpyridine)

Fundamental understanding of microphase separation in ABC miktoarm copolymers is vital to access a plethora of nonconventional morphologies. Miktoarm stars based on poly(cis 1,4-isoprene) (I), poly(styrene) (S), and poly(2-vinylpyridine) (V) are model systems, which allow systematic studies of the effects of composition, chemical microstructure, and temperature on the thermodynamics of microphase separation. Eleven ISV-x (I:S:V = 1:1:x, v:v:v) miktoarm copolymers were synthesized by anionic polymerization affording well-defined copolymers with a variable V arm. Equilibrium bulk morphologies of all samples, as evidenced by small-angle X-ray scattering, transmission electron microscopy (TEM), and self-consistent field theory, showed a systematic transition from lamellae (x ≈ 0–0.2) to [8.8.4] tiling (x ≈ 0.6–0.9) to cylinders in undulating lamellae (x ≈ 2–4) and, finally, to hexagonally packed core–shell cylinders (x ≈ 5–8). Chemical microstructure of the I arm [poly(cis 1,4-isoprene)] versus poly(3,4-isoprene) is shown to play important role in affecting morphological behavior. To reconcile differences between ISV-x star morphologies reported in the literature and those reported herein, even for the same composition, effects of the microstructure of I arm on the Flory–Huggins parameter between I and V arms were taken into account in a qualitative manner. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2018 , 56, 1491–1504