傅立叶变换红外光谱法定量测定PVC玩具中的DEHP

采用傅立叶变换红外光谱法对PVC玩具中的DEHP含量进行了定量测定 ,该方法简单 ,结果可靠 ,适合于流水线的质量控制。又采用气相色谱法对同一样品进行测试 ,结果表明这两种方法的测试结果无显著性差异。     

The ionic hall effect in the solid electrolyte C5H6NAg5I6

The ionic Hall effect was measured in polycrystalline C₅H₆NAg₅I₆ at 25°C using an ac electric field and a dc magnetic field. The Hall voltages ranged between 10 and 100nV for magnetic fields of 0.1-T. From these data we calculated the average Ag⁺ ion mobility, the number of mobile Ag⁺ ions per cm³, the percentage of free silver ions, and the average relaxation time. We conclude that the exceptionally high ionic conductivity in C₅H₆NAg₅I₆ at 25°C probably arises from a relatively small number of mobile Ag⁺ ions.     

Boosting C2H6/C2H4 separation in scalable metal-organic frameworks through pore engineering

The development of ethane (C₂H₆)-selective adsorbents for ethylene (C₂H₄) purification, although challenging, is of prime industrial importance. Pillared-layer metal-organic frameworks (MOFs) possess facilely tunable pore structure and functionality, which means they have excellent potential for high-performance C₂H₆/C₂H₄ separation applications. Herein, we report a family of isostructural pillared-layer MOFs with various metal centers M and co-ligands L, M₂(D-cam)₄L₂ (denoted M-cam-L; M = Cu, Co, Ni; L = pyz, apyz, dabco), with a variety of pore surface properties. All of the M-cam-L materials exhibit preferential adsorption for C₂H₆ over C₂H₄. In particular, Ni-cam-pyz exhibits the highest C₂H₆ capture capacity (68.75 cm³ g⁻¹ at 1 bar and 298 K), Cu-cam-dabco possesses the greatest C₂H₆/C₂H₄ adsorption selectivity (2.3), and the lowest isosteric heat of adsorption is demonstrated for Cu-cam-pyz (20.1 kJ mol⁻¹). Dynamic column breakthrough experiments also confirmed the excellent separation performance of M-cam-pyz and M-cam-dabco materials. The synthesis route of the M-cam-L materials is easily scaled-up under laboratory conditions, and hence this class of MOFs is promising for practical C₂H₄ purification.     

Dependence of selective reduction of NO with C3H6 on acid properties of ion-exchanged zeolites

The effect of amount and strength of acid sites on the activity and selectivity for the selective reduction of NO with C₃H₆ in the presence of excess oxygen over H-form and ion-exchanged zeolites has been investigated. The activity was found to be proportional to the acid amount determined by NH₃-temperature programmed desorption, but independent of the acid strength of the zeolites. The selectivity, i.e., the ratio of the reduction of NO with C₃H₆ to the oxidation of C₃H₆ by O₂, was independent of the amount and strength of acid sites.     

Synthesis,spectroscopic and structural aspects of triphenylantimony(V) complex with internally functionalized acetylferroceneoxime: Crystal and molecular structures of [C5H5FeC5H4C(CH3)NO]2SbPh3 and C5H5FeC5H4C(CH3)NOH

Triorganoantimony(V) complex (C₅H₅FeC₅H₄C(CH₃)NO)₂SbPh₃ (1) has been prepared by the reaction of Ph₃SbCl₂ with acetylferroceneoxime C₅H₅FeC₅H₄C(CH₃)NOH (2) in 1:2 molar ratio in anhydrous toluene. The complexes have been characterized by elemental analyses, IR and NMR (¹H and ¹³C) spectroscopic studies, and biologic activity was measured. And crystal structures of 1, 2 were reported. The coordination geometry around the antimony atom in 1 was slightly distorted trigonal bipyramidal with the carbon atoms of the SbPh₃ unit in equatorial positions and the two oxygen atoms of the oxime group occupying axial positions. The free oxime was clearly hydrogen bonded (H–N 2.10 Å/2.04 Å in 2) to essentially form a dimer.     

CH4/C2H6/C3H8在MOF-505@5GO上吸附相平衡和选择性

应用溶剂热法合成了不同氧化石墨烯（GO）负载量的MOF-505@GO复合材料,分别采用全自动表面积吸附仪、P-XRD、SEM和Raman对材料进行了性能表征,测定了CH₄、C₂H₆和C₃H₈在MOF-505@GO上的吸附等温线,并进行Langmuir-Freundlich方程拟合,依据IAST理论模型计算了C₂H₆/CH₄和C₃H₈/CH₄二元混合气在MOF-505@5GO上的吸附选择性。研究结果表明,随着GO负载量增大,MOF-505@GO复合材料的孔容及BET比表面积先增大后减小,当GO负载量为5%（质量）时,复合材料MOF-505@5GO的孔容及BET比表面积达到最大,当GO负载量进一步增大至8%（质量）和10%（质量）时,复合材料的孔容及BET比表面积逐渐降低。在0.1 MPa和298 K条件下,MOF-505@5GO对CH₄、C₂H₆和C₃H₈的吸附容量分别为0.88、4.81和5.17 mmol·g^-1,相比MOF-505分别提高了14.9%、30.7%和13.1%。MOF-505@5GO对C₂H₆/CH₄和C₃H₈/CH₄的吸附选择性分别为40.1和3056.1,其对C₂H₆/CH₄和C₃H₈/CH₄具有极高的吸附选择性。     

有机锡化合物(C6H5)3SnCl的合成及晶体结构

合成了有机锡化合物(C6H5)3SnCl,通过元素分析、红外光谱和核磁共振氢和锡谱对其结构进行了表征。用X-射线单晶衍射测定了该化合物的晶体和分子结构。化合物晶体为三斜晶系,空间群P,īa=9.740(9),b=18.674(17),c=19.010(17),α=105.513(14)°,β=90.036(14)°,γ=90.258(15)°,V=3 332(5)3,Z=8,Dc=1.537 Mg/m3,μ=1.682mm-1,F(000)=1 520,R=0.045 8,wR=0.103 0。锡原子呈畸变四面体构型。     

Production of biodiesel from soybean oil catalyzed by attapulgite loaded with C4H5O6KNa catalyst

Biodiesel is a green, safe, renewable alternative fuel, which is of great significance to solving the problem of energy shortage and environmental pollution. A series of solid base catalysts were prepared with the support of attapulgite (ATP), the load of C₄H₅O₆KNa by impregnation method, and were used to catalyze transesterification of soybean oil with methanol to biodiesel. The activities of prepared catalysts were investigated compared to pure ATP. The optimal conditions for the catalyst preparation were investigated: molar ratio of Na: ATP was 1.7: 1 and calcination temperature was 400 °C. The prepared catalysts were characterized by several techniques such as Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, N₂ adsorption-desorption measurements, X-ray diffraction and the Hammett indicator method. The prepared solid base catalyst can be separated from reaction system effectively and easily. The effects of the molar ratio of methanol to oil, reaction temperature and amount of catalyst on the biodiesel yield were investigated. The experimental results showed that a 22: 1 molar ratio of methanol to oil, 10.0% of catalyst amount, 65 °C of reaction temperature and 3.0 h of reaction time gave the best results. The catalyst has longer lifetime and maintained sustained activity after being used for five cycles.     

Permeation of H2, N2, CH4, C2H6, and C3H8 through asymmetric polyetherimide hollow‐fiber membranes

Permeation properties of pure H₂, N₂, CH₄, C₂H₆, and C₃H₈ through asymmetric polyetherimide (PEI) hollow‐fiber membranes were studied as a function of pressure and temperature. The PEI asymmetric hollow‐fiber membrane was spun from a N‐methyl‐2‐pyrrolidone/ethanol solvent system via a dry‐wet phase‐inversion method, with water as the external coagulant and 50 wt % ethanol in water as the internal coagulant. The prepared asymmetric membrane exhibited sufficiently high selectivity (H₂/N₂ selectivity >50 at 25°C). H₂ permeation through the PEI hollow fiber was dominated by the solution‐diffusion mechanism in the nonporous part. For CH₄ and N₂, the transport mechanism for gas permeation was a combination of Knudsen flow and viscous flow in the porous part and solution diffusion in the nonporous part. In our analysis, operating pressure had little effect on the permeation of H₂, CH₄, and N₂. For C₂H₆ and C₃H₈, however, capillary condensation may have occurred at higher pressures, resulting in an increase in gas permeability. As far as the effect of operating temperature was concerned, H₂ permeability increased greatly with increasing temperature. Meanwhile, a slight permeability increment with increasing temperature was noted for N₂ and CH₄, whereas the permeability of C₂H₆ and C₃H₈ decreased with increasing temperature. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 698–702, 2002     

C5/C6烷烃异构化技术及进展

C5/C6烷烃异构化技术可以使轻石脑油的辛烷值提高约20个单位,其产品异构化油是一种高辛烷值且环境友好的汽油调和组份。国外的C5/C6异构化技术主要有UOP的Penex、Axens的Isomerization等。国内的技术有石科院的RISO和华东理工大学的技术等。通过对国内外的主要C5/C6异构化技术进行对比分析,为国内的异构化技术发展提出建议。     

我国Ｃ５／Ｃ６烷烃异构化催化剂研究进展

２０世纪８０年代以来,由于环保的要求,Ｃ_５／Ｃ_６烷烃异构化工艺在国外得到迅速发展,并已成为生产高辛烷值汽油组分的重要工艺。我国目前尚无轻烃异构化装置,但国内许多部门进行了Ｃ_５／Ｃ_６异构化催化剂的研究,为Ｃ_５／Ｃ_６异构化工业生产做好了准备。     

Study of the preparation of bulk tungsten carbide catalysts with C2H6/H2 and C2H4/H2 carburizing mixtures

The influence of the preparation procedure of tungsten carbide on the mechanism of carburization is discussed. This work is focused on the reduction and the carburization of tungsten trioxide by a mixture of hydrocarbon and H₂ to form WC. Temperature-programmed reaction spectra obtained with CH₄, C₂H₆ and C₂H₄ have been measured. In presence of the CH₄-H₂ mixture, H₂ is the reducing agent and the hydrocarbon is consumed for the carburization whereas C₂H₆ or C₂H₄ participates in the reduction of the tungsten oxide. The temperatures of reduction and carburization are lower by about 150 K using C₂H₆ or C₂H₄ instead of CH₄. Such a decrease of the temperature of reduction of tungsten oxide is needed to avoid the formation of poorly reducible compounds that can occur during the preparation of supported tungsten carbide. Furthermore, the surface area of the resulting carbide is 25 m²/g with C₂H₆ and C₂H₄ and 10 m²/g with CH₄. During the carburization, the deposit of excess carbon on the WC surface is larger with the C₂ hydrocarbons than with CH₄, but it protects the carbide and can be removed by hydrogen treatment. This revised version was published online in July 2006 with corrections to the Cover Date.     

Post-discharge kinetics associated with a plasmachemical nucleophilic substitution and application to the analysis of plasma activated CO

The UV-visible absorbance spectra of aqueous solutions of pentacyano (N.methyl pyrazinium) ferrate(II) complex exposed to the flux of neutral activated species of a DC corona discharge in CO at atmospheric pressure are deeply modified: the blue color of the starting complex fades, which is not observed in ordinary conditions. The overall kinetic law is found to be zero-order and interpreted in terms of ligand exchange reaction (i.e., a nucleophilic substitution reaction induced by D.C. corona discharge) by comparison with literature result relevant to the exchange of other ligands in solution. Additionally, post-discharge phenomena induced by the plasma treatment are also observed. They obey an overall 1st order kinetic law under our working conditions. The influence of the most salient working parameters on the post discharge kinetic rate is examined. The electric power provided to the discharge is probably the most important factor for controlling the post-discharge kinetic rate. The results obtained also suggest a new analytical technique to quantify activated CO.     

双核苯甲酸铜配合物单晶的流变相合成与表征

采用流变相反应法合成了苯甲酸氢铜的大颗粒单晶,借助元素分析、四圆单晶衍射分析表征其组成和晶体结构,得到的晶体学数据如下:苯甲酸氢铜为单斜晶系,空间群P21/n,a=1.079 9(2)nm,b=1.178 0(2)nm,c=1.530 3(3)nm,β=91.35(3)°,V=1.946 1(7)nm3,Z=4,ρcalc=1.460,ρexp=1.455 g/cm3。μ=1.156 mm-1,F(000)=876,S=0.990,最终的偏离因子R=0.056 0和wR=0.075 0[I>2σ(I)]。用磁天平测定了晶体的磁化率。借助扫描电子显微镜研究了原料反应物颗粒的大小和生长单晶的颗粒大小存在有密切关系,探讨了在流变相体系中的化学反应机理和单晶生长机理,发现在流变相体系中存在有分子识别和自组装功能。     

[Fe(C7H5O3)(C9H6NO)2]三元配合物的合成及抑菌性能

本文以水杨酸、8-羟基喹啉为配体与铁(Ⅲ)合成了三元配合物,用元素分析、红外光谱、紫外可见光谱、荧光光谱等手段对其进行表征,确定其化学组成为[Fe(C7H5O3)(C9H6NO)2]。其中水杨酸脱质子以羧酸根与Fe3+成键,酚羟基不参与配位,而8-羟基喹啉脱质子以酚羟基氧和杂环上的氮原子双齿配位,形成五元螯环。配合物在整个可见光区都有较强吸收,粉末及其浓溶液均呈黑色,稀溶液显紫色。以300 nm为激发波长时,三元配合物在409 nm处有较强的发射荧光。采用分光光度法研究其对大肠杆菌生长的作用,配合物摩尔浓度低于2 mmol/L时,促进大肠杆菌的生长,高于2 mmol/L时抑制其生长,浓度越大抑制作用越强,即配合物对大肠杆菌的生长具有双向生物效应。     

[Fe(C7H5O3)(C9H6NO)2]三元配合物的合成及抑菌性能

以水杨酸、8-羟基喹啉为配体与铁(Ⅲ)合成了三元配合物,用元素分析、红外光谱、紫外可见光谱、荧光光谱对其进行表征,确定其化学组成为[Fe(C7H5O3)(C9H6NO)2]。其中,水杨酸脱质子以羧酸根与Fe3+成键,酚羟基不参与配位,而8-羟基喹啉脱质子以酚羟基氧和杂环上的氮原子双齿配位,形成五元螯环。配合物在整个可见光区都有较强吸收,粉末及其浓溶液均呈黑色,稀溶液呈紫色。以300 nm为激发波长时,三元配合物在409 nm处有较强的发射荧光。采用分光光度法研究其对大肠杆菌生长的作用,配合物浓度低于2 mmol/L时,促进大肠杆菌的生长,高于2 mmol/L时抑制其生长,浓度越大抑制作用越强,即配合物对大肠杆菌的生长具有双向生物效应。     

Dicyclohexano-18-crown-6 as active material in PVC matrix membrane for the fabrication of cadmium selective potentiometric sensor

PVC based membrane containing dicyclohexano-18-crown-6 (I) as active material along with sodium tetraphenyl borate (NaTPB) as an anion excluder and dibutyl phthalate as solvent mediator in the ratio 20:4:150:150 (w/w) (I-NaTPB-DBP-PVC) exhibits good properties with a Nernstian response of 29.0±1.0 mV per decade of activity and a working concentration range of 2.1×10⁻⁵-1.0×10⁻¹ M. The working pH range of the sensor is 1.9-7.0. It exhibits a fast response time as fast as 17 s and has a lifetime of about 6 months. The proposed sensor has good selectivity for cadmium over alkali, alkaline earth, some transition and heavy metal ions. The sensor works satisfactorily in mixtures having 10% (v/v) non-aqueous content without showing any considerable change in working concentration range or slope. It has been successfully used as an indicator electrode for the potentiometric titration of Cd²⁺ against EDTA as well as for its determination in wastewaters.     

影响C5树脂碘值测定结果的因素

研究了称样量范围及试验温度对C5树脂碘值测定结果的影响。试验结果表明 ,C5树脂碘值测定结果随称样量的增大而减小 ,随试验温度的升高而增大。确定C5树脂碘值测定的称样量范围为 (0 .2 0 0 0± 0 .0 0 5 0 )g ,试验温度为 2 5℃左右。     

磷钨钼酸催化合成4-苯基-6-甲基-5-乙氧羰基-3，4-二氢嘧啶-2（H）-酮

以磷钨钼杂多酸为催化剂，无水乙醇为溶剂，苯甲醛、乙酰乙酸乙酯、尿素为原料，合成了4-苯基-6-甲基-5-乙氧羰基-3，4-二氢嘧啶-2（H）-酮，系统研究了催化剂用量、反应温度、反应时间、原料配比诸因素对产品收率的影响。实验表明：磷钨钼杂多酸是合成4-苯基-6-甲基-5-乙氧羰基-3，4-二氢嘧啶-2（H）-酮的良好催化剂。确定的最优合成工艺条件为：尿素37．5mmol时，n（苯甲醛）：n（乙酰乙酸乙酯）：n（尿素）=1：1．2：1．5，催化剂用量为反应物料总质量的1．5%，反应温度为60℃，反应时间1．0h。在此条件下，产品收率可达44．6%.