复合载体TiO2-Al2O3的制备及其对Ni-Mo-S负载型催化剂加氢脱氧性能的影响

采用共沉淀法制备出复合载体TiO₂-Al₂O₃,用N₂-吸附、XRD和吡啶吸附红外光谱等手段进行表征。采用原位硫化法制备Ni-Mo-S/TiO₂-Al₂O₃负载型催化剂,以苯酚为模型化合物研究其加氢脱氧催化性能。主要研究铝源和沉淀剂对TiO₂-Al₂O₃复合载体性能的影响以及其作为载体对Ni-Mo-S/TiO₂-Al₂O₃催化苯酚加氢脱氧反应的影响。结果表明,以氯化铝为铝源制备的复合载体具有较大的孔容和孔径,孔容达1.12cm³/g,孔径达18.0nm;以硫酸铝为铝源和以碳酸氢铵为沉淀剂制备的复合载体具有较大的比表面积,高达295m²/g;氨水沉淀制备的复合载体具有较多的L酸;以硫酸铝为铝源制备的复合载体形成少量的B酸。TiO₂-Al₂O₃作为载体影响Ni-Mo-S/TiO₂-Al₂O₃负载型催化剂加氢脱氧性能的主要因素是载体的酸性和载体的比表面积。在300℃,4.0MPa条件下Ni-Mo-S/TiO₂-Al₂O₃催化苯酚的转化率达81.9%,产物中无氧化合物的总选择性达100%,脱氧率达79.4%。     

Synthesis of fluorodinitromethane and 2-fluoro-2, 2-dinitroethanol

Conclusions The authors have obtained fluorodinitromethane and 2-fluoro-2, 2-dinitroethanol and studied some of their physiocochemical properties.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 912–914, April, 1968.     

Thiophene-2-aryl-2H-benzotriazole-thiophene oligomers with adjustable electronic properties

The synthesis and the optical and electrochemical properties of 2-aryl-2H-benzotriazole based thiophene oligomers with chemical modifications either on the phenyl side group or on the backbone are presented. All data, supported by DFT calculations, show that modification on the backbone has a major impact on the electronic properties while the side groups can fine-tune the electronic properties. In addition, one compound exhibits a thermotropic mesophase.     

Thermal reaction of clCH2CONH2 in molten acetamide

Mixtures composed of amides and electrolytes exhibit interesting properties such as viscoelastic behaviour and a megavalue of the dielectric constant. In order to improve the dielectric properties, the authors are investigating a large number of molten mixtures of CF₃COONa with different types of amides, including the ternary system sodium trifluoroacetate-chloroacetamide-acetamide. The experimental measurements showed that the ternary mixtures are thermally unstable. A yellow oily product is formed; this was purified and tested by means of IR and NMR techniques. The formula and the kinetic mechanism are proposed.     

Electronic basis of the comparable hydrogen bond properties of small H2CO/(H2O)n and H2NO/(H2O)n systems (n = 1, 2)

The electronic and structural properties of dihydronitroxide/water clusters are investigated and compared to the properties of formaldehyde/water clusters. Exploring the stationary points of their potential energy surfaces (structurally, vibrationally, and energetically) and characterizing their hydrogen bonds (by both atoms in molecules and natural bond orbitals methods) clearly reveal the strong similarity between these two kind of molecular systems. The main difference involves the nature of the hydrogen bond taking place between the X-H bond and the oxygen atom of a water molecule. All the properties of the hydrogen bonds occurring in both kind of clusters can be easily interpreted in terms of competition between intermolecular and intramolecular hyperconjugative interactions.     

La3+,Sr2+置换对Ca[(Mg1/3Nb2/3)0.6Ti0.4]O3陶瓷微波介电性能的影响

研究了La^3＋，Sr^2＋置换对Ca[（Mg1/3Nb2/3）0.6Ti0.4]O3陶瓷微观结构与微波介电性能的影响。研究结果表明：La^3＋，Sr^2＋置换改性Ca[（Mg1/3Nb2/3）0.6Ti0.4]O3系列陶瓷均形成了单一正交系的钙钛矿结构；随着置换量的增加，La^3＋改性Ca[（Mg1/3Nb2/3）0.6Ti0.4]O3陶瓷的介电常数、介电损耗下降，同时谐振频率温度系数向正的方向移动，而Sr^2＋改性陶瓷则表现出相反的规律，其主要原因在于La^3＋，Sr^2＋置换所引起Ca[（Mg1/3Nb2/3）0.6TiO4]O3陶瓷内部氧八面体结构变化上的差异。     

Mg(NH2)2-2LiH储氢材料的研究进展

Mg(NH₂)₂-2LiH 材料是近年来发展起来的几种最具应用潜力的高容量储氢材料之一. 由于具有较合适的吸放氢热力学性能、相对较低的吸放氢操作温度、较高的可逆储氢容量和较优的吸放氢循环稳定性,Mg(NH₂)₂-2LiH 材料现已成为储氢材料研究领域的一个热点. 本文综述了Mg(NH₂)₂-2LiH 材料近年来的研究进展, 重点关注了材料的组分、晶体结构、颗(晶)粒尺寸和催化动力学改性等对材料储氢性能的影响及储氢机理,总结了Mg(NH₂)₂-2LiH 储氢材料存在的技术问题并指出了今后的研究方向.     

Sol of Hydrated ZrO2–TiO2System

A hydrated zirconium titanate sol was obtained by the electrochemical method. Properties of this sol were compared with the properties of a mixture of hydrosols of titanium and zirconium dioxides.     

Y2O3和CeO2对氮化硅烧结性能的影响

研究了Y2O3,CeO2的添加量在不同烧结温度下对Si3N4烧结性能的影响，分析了其助烧作用及晶界二次小晶粒形成的机制。结果表明，添加Y2O3,CeO2的Si3N4其烧结性能良好。Y2O3添加5％（此时Al2O3含量为4％）及CeO2为8％时对制品烧结促进作用最大。热处理后在Si3N4晶界获得结晶完美的二次小晶粒，使晶界玻璃相大为下降，为Si3N4高温力学性能的提高奠定结构基础。     

Physicochemical Study of Ta2O5 and SiO2-Ta2O5 Film Formation from Film-Forming Solutions

In order to study physicochemical processes of formation of Ta₂O₅ and SiO₂-Ta₂O₅ films from film-forming solutions, the properties of these solutions, and also the thermal-oxidative breakdown and the properties of the obtained films, were studied.     

Synthesis of new 2-(4-vinyl-2H-chromen-2-ylidene)malononitrile-based chromophores

Russian Chemical Bulletin - An approach towards new 2-(4-vinyl-2H-chromen-2-ylidene)malononitriles-derived chromophores was developed. The optical, solvatochromic, and electrochemical properties of...     

Photoluminescence from (Si/SiO2)n superlattices and their use as emitters in [SiO2/Si]n SiO2 [Si/SiO2]m microcavities

Si/SiO2 superlattices are recently under investigation to add optical functionality to silicon based microelectronics. In such superlattices quantum-confinement should drive Si to become a good light emitter. Emission properties can be further improved and controlled by placing the emitter in optical microcavities. In this paper emission properties of (Si/SiO2), superlattices grown by Low Pressure Chemical Vapour Deposition will be compared with the ones obtained by other growth techniques and the origin of the emission will be discussed. Emission properties can be further improved and controlled by placing the emitter in optical microcavities. Optical properties of microcavities produced with standard complementary metal-oxide-semiconductor techniques containing Si/SiO2 superlattices as light emitter will be reviewed and a comparison between properties estimated from calculations and experiments will be given.     

Reaction of 2-acetylbenzothiazole with 2-formylbenzothiazole

Products of condensation of 2-acetylbenzothiazole with 2-formylbenzothiazole and other aldehydes of the heterocyclic series were obtained, and their structures and properties were investigated. It is shown that some of them react with acids or alkalis to give dyes.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 644–648, May, 1982.     

Enhancement of intercalation properties of V2O5 film by TiO2 addition

Although it is well-known that TiO2 incorporation can greatly improve the cyclic stability of V2O5, the influences of TiO2 addition on the Li+ intercalation properties of V2O5 remain an issue of debate in literature. In this paper, we report on a systematic investigation of the preparation and intercalation properties of V2O5-TiO2 mixture films. The present work demonstrates that high Li+ intercalation rates and capacity in V2O5 films are achievable with TiO2 addition. For example, the addition of 20 mol % Ti into V2O5 polycrystalline demonstrated an approximated 100% improvement in Li+ intercalation performance as compared to single V2O5 electrodes. Such enhancement in intercalation properties of V2O5 films with TiO2 addition was attributed to changes in microstructure, crystallinity, and also a possible lattice structure and interaction force between adjacent layers in V2O5.     

2-乙基己基膦酸2-乙基己基酯钠皂微乳液

HA( 2-乙基己基膦酸 2-乙基己基酯 )是一种性能优良的萃取剂,经皂化形成微乳液后,能大大提高萃取率 .许多学者对含有中长链醇等助表面活性剂的 HA碱皂微乳液的物理化学性质进行了深入的研究 [1－ 4].　　本文报导了用 NaOH皂化不含任何助表面活性剂的 HA煤油溶液,当体系中的 NaOH与 HA数量比达到一定值时,会形成稳定的 W/O型微乳液 .不同的 nNaOH:nHA形成的微乳液的状态可能有所不同 .对这种不含助表面活性剂的微乳液的相行为、电导、溶水量等物理化学性质进行了初步研究 .1实验部分 （ 1） 仪器和试剂 DDS-11A型电导率仪,上…     

Electrical properties of single-crystalline CaAl2Si2

Electrical resistivity and Hall coefficient measurements of single-crystalline CaAl(2)Si(2) revealed that CaAl(2)Si(2) is a metal in which both electrons and holes contribute to the transport properties; its dominant carriers are holes at temperature below 150 K but electrons above that temperature.     

二维材料范德华间隙的利用

Since their discovery, two-dimensional (2D) materials have attracted significant research attention owing to their excellent and controllable physical and chemical properties. These materials have emerged rapidly as important material system owing to their unique properties such as electricity, optics, quantum properties, and catalytic properties. 2D materials are mostly bonded by strong ionic or covalent bonds within the layers, and the layers are stacked together by van der Waals forces, thereby making it possible to peel off 2D materials with few or single layers. The weak interaction between the layers of 2D materials also enables the use of van der Waals gaps for regulating the electronic structure of the system and further optimizing the material properties. The introduction of guest atoms can significantly change the interlayer spacing of the original material and coupling strength between the layers. Also, interaction between the guest and host atom also has the potential to change the electronic structure of the original material, thereby affecting the material properties. For example, the electron structure of a host can be modified by interlayer guest atoms, and characteristics such as carrier concentration, optical transmittance, conductivity, and band gap can be tuned. Organic cations intercalated between the layers of 2D materials can produce stable superlattices, which have great potential for developing new electronic and optoelectronic devices. This method enables the modulation of the electrical, magnetic, and optical properties of the original materials, thereby establishing a family of 2D materials with widely adjustable electrical and optical properties. It is also possible to introduce some new properties to the 2D materials, such as magnetic properties and catalytic properties, by the intercalation of guest atoms. Interlayer storage, represented by lithium-ion batteries, is also an important application of 2D van der Waals gap utilization in energy storage, which has also attracted significant research attention. Herein, we review the studies conducted in recent years from the following aspects: (1) changing the layer spacing to change the interlayer coupling; (2) introducing the interaction between guest and host atoms to change the physico-chemical properties of raw materials; (3) introducing the guest substances to obtain new properties; and (4) interlayer energy storage. We systematically describe various interlayer optimization methods of 2D van der Waals gaps and their effects on the physical and chemical properties of synthetic materials, and suggest the direction of further development and utilization of 2D van der Waals gaps.     

Anodic carbidation of tantalum in molten CaCl2-CaC2

Journal of Solid State Electrochemistry - Making a tantalum carbide (TaC) coating on Ta substrates is an effective way to improve the mechanical and anti-corrosion properties of Ta. However,...     

Synthesis, properties and prodrug potential of 2-methyl-2-oxy- and 2-methyl-2-thio-4H-1,3-benzodioxin-4-ones

The fifty-four known title compounds are fully documented and their chemical and biological properties discussed in detail. Special attention is devoted to their potential as aspirin and salicylic acid prodrugs, respectively.     

Effect of acid-base properties of the medium on the reactions in the 2-furaldehyde-H2O2-H2O system with and without VOSO4

Data on the effect of acid-base properties of the medium in the pH range 0–9 on the intensity of transformation of 2-furaldehyde and the direction of the multi-stage reactions in the 2-furaldehyde-H₂O₂-H₂O system in the presence of VOSO₄ and without it are presented. Significant influence of the medium pH value on the reaction pathway in the system under investigation hase been found. Mechanism of these reactions considering the effect of acid-base properties of the medium has been suggested.