Fabrication of superhydrophilic surface on copper substrate by electrochemical deposition and sintering process

Superhydrophilic surfaces were fabricated on copper substrates by an electrochemical deposition and sintering process. Superhydrophobic surfaces were prepared by constructing micro/nano-structure on copper substrates through an electrochemical deposition method. Conversion from superhydrophobic to superhydrophilic was ob-tained via a suitable sintering process. After reduction sintering, the contact angle of the superhydrophilic sur-faces changed from 155° to 0°. The scanning electron microscope (SEM) images show that the morphology of superhydrophobic and superhydrophilic surfaces looks like corals and cells respectively. The chemical composi-tion and crystal structure of these surfaces were examined using energy dispersive spectrometry (EDS) and X-ray diffraction (XRD). The results show that the main components on superhydrophobic surfaces are Cu, Cu2O and CuO, while the superhydrophilic surfaces are composed of Cu merely. The crystal structure is more inerratic and the grain size becomes bigger after the sintering. The interfacial strength of the superhydrophilic surfaces was investigated, showing that the interfacial strength between superhydrophilic layer and copper substrate is considerably high.     

Carbonization of Ni-doped Phenol Resin Under Various Conditions

Ni-doped phenol resin was prepared with 1∶100 mass ratio of Ni( NO_3)_2·6H_2O to thermosetting phenol resin to optimize the structure and properties of pyrolytic carbon derived from phenol resin and increase its carbon yield. The specimens were cured at 200 ℃ and carbonized under different atmospheres( carbon-embedded atmosphere and Ar atmosphere) and at different temperatures( 600,800,1000 and 1200 ℃) for3 h,respectively. The carbon yield was measured. Thermal decomposition characteristics of Ni-doped phenol resin,and the oxidation resistance,phase composition and microstructure of pyrolytic carbon were characterized by differential scanning calorimetry,X-ray diffraction,energy dispersive spectroscopy, scanning electron microscopy and transmission electron microscopy. The results show that the carbon yield of Ni-doped phenol resin carbonized at800 or 1 000 ℃ is increased significantly,compared with that without any dopants. The graphitization degree of pyrolytic carbon structure derived from Ni-doped phenol resin increases with the increase of carbonization temperature. The massive multi-wall carbon nanotubes of 50-100 nm in diameter and of micrometre scale in length are generated at 1000 ℃. Compared with the carbonembedded atmosphere,carbon nanotubes can be more easily generated in Ar atmosphere,resulting in higher carbon yield and degree of crystallinity of the pyrolyticcarbon derived from Ni-doped phenol resin. The oxidation resistance of the pyrolytic carbon derived from Ni-doped phenol resin at 1200 ℃ is improved significantly and its highest oxidation temperature is increased by about 84℃,compared with that from Ni free phenol resin.     

Effect of pyrolytic carbon interphase on mechanical properties of mini T800-C/SiC composites

The effect of pyrolytic carbon(PyC) thickness on the tensile property of mini T800 carbon fiber reinforced SiC matrix composites(C/SiC) was studied. PyC interphase was prepared by chemical vapor infiltration(CVI) process using C3H6–Ar as gas source, the PyC thickness was adjusted from 0 to 400 nm, and then the SiC matrix was prepared by CVI process using methyltrichlorosilane(MTS)–H2–Ar as precursor and gas source. The results showed that the tensile strength of mini T800-C/SiC increased first and then decreased with the increase of the PyC thickness. When the thickness of PyC was 100 nm, the average strength reached the maximum value of 393 ± 70 MPa. The Weibull modulus increased from 2.0 to 8.06 with the increase of PyC thickness, and the larger the Weibull modulus, the smaller the dispersion, which indicated that the regulation of PyC thickness was conducive to improve tensile properties.     

乙醇对铝掺杂二氧化钦介孔材料的固相反应合成及其电化学性能的影响(英文)

Mesoporous aluminum-doped titanium dioxide(Al-TiO2) materials with high specific surface areas were prepared via a solid-state reaction route.The properties of these materials were characterized by X-ray diffraction(XRD),high resolution transmission electron microscopy(HRTEM),energy dispersive spectroscopy(EDS),N2 absorption-desorption,ultraviolet visible light spectroscopy(UV-Vis) and electrochemical spectroscopy.The results show that the mesoporous structure of the product with ethanol is composed of anatase laced crystal walls with amorphous grain boundaries formed gradually by degradation.Compared with those without ethanol,these samples possess larger crystallite size since ethanol decreases the pore size at higher temperature.With the increase of ethanol amount,however,the crystallite size will grow.The amorphous grain boundaries in the mesoporous material,with a large impedance and low incidental cyclic potential,are difficult to effectively degrade and the phase transformation temperature is changed from 500 to 550℃.The growth rate of Al-TiO2 crystallites that obeys the quadratic polynomial equation may be controlled.     

Rapid synthesis of CNTs@MIL-101(Cr) using multi-walled carbon nanotubes (MWCNTs) as crystal growth accelerator☆

In this work,hybrid material CNTs@MIL-101(Cr) was synthesized in 2 h using multi-walled carbon nanotubes(MWCNTs) as the crystal growth accelerator with hydrothermal method.The characteristic differences between the crystals of CNTs@MIL-101(Cr) and MIL-101 were investigated by N_2 adsorption–desorption isotherms,X-ray diffraction(XRD),scanning electron microscope(SEM) and thermogravimetric analyzer(TGA).The results showed that MWCNTs embedding in the hybrid material provide more mesoporous volumes than that of MIL-101.Moreover,the fast synthesized crystals of CNTs@MIL-101(Cr) still preserve the octahedral shape like MIL-101 and have a larger size ranging from 1.5 to 2.0 μm which were approximately three times larger than that of MIL-101.In the proposed mechanism,the roles of MWCNTs played in the crystallization were discussed where MWCNTs can be seen as coaxial cylindrical tubes composed of multi-layer graphenes and the place where nucleation and crystal growth processes occur at the tubes' out surface.Then,a crystal seeding layer bonding with the MWCNTs may be easily formed which accelerates the growth rate of MIL-101 crystals.Thus,larger crystals of CNTs@MIL-101(Cr) were formed due to the faster crystal growth rate of MIL-101.     

Al4C3 Hydration Thermochemical Analysis for Burned Carbon-Containing Refractories with Al

In this paper,X-ray diffractogram analysis and SEM observation of Al4C3 formed at high temperature from carbon-containing refractories with Al have been carried out.Aluminum added to carbon-containing refractories reacts with C(s) to form Al4C3(s) gradually during heating from 600℃ to 1200℃，It is considered that the interlocked structure of Al4C3 plate crystals promotes the outstanding increase of hot modulus of rupture of carbon-containing refractories with Al.The HMOR of carbon-contatining refractories with Al.The HMOR of carbon-containing refractories added with Al additive from 0 to 5wt% increases by 2.8 times being from 6.5MPa to 18.2MPa.After a thermochemical Calculation for hydration reaction Processes of Al4C3 and H2O(g),the equilibrium partial pressure chart of H2O(2)in H2O-Al4C3-Al(OH)3 system vs various temperatures has been attained.The H2O(g) partial pressure in the air needed for the Al4C3 hydration reaction is no more than 10-18 atm at the temperature below 120℃。It is considered that the temperature below 120℃. It is considered that the burned carbon-containing refractories with Al is extremely easy to hydrate and the cracking of buurned carbon-containing refractories is generated because that the hydration expansion is 2.11 times during transforming from Al4C3 to Al(OH)3.The fundamental measure against hydration of the refractories is to insulate the refractories from H2O(g) by various means such as pitch impregnatiion or other sealing materials.     

偶联阳离子表面活性剂和常用阴离子表面活性剂混合溶液的相分离和微观结构

The properties of aqueous two-phase system (ATPS) of mixed solution containing gemini cationic surfactant trimethylene-l,3-bis(dodecyldimethyl ammonium) bromide (12-3-12, 2Br-) and traditional anionic surfactant sodium dodecyl sulfate (SDS) with or without added salt have been studied. An ATPS is formed in a narrow region of the ternary phase diagram different from that of traditional aqueous cationic-anionic surfactant systems. In ATPS region, the lowest total concentration of surfactants varies with the mixing ratio of geminis to SDS. Photographs obtained from freeze-etching, negative-staining and transmission electron microscopy show that the microstructures of two phases are different from each other. Micelles and vesicles can coexist in a single phase. The addition of salts can change the phase diagram of ATPS. Furthermore, the added salts promote the aggregation of rod-like micelles to form coarse network structure that increase the viscosity of solutions. The negative ions of the added salts are the determining factor.     

池式沸腾下PAA与PBTCA对CaCO3结垢的影响

Formation of mineral scales on heat exchangers is a persistent and expensive problem.In the present paper,the calcium carbonate scale inhibition by two inhibitors,polyacrylic acid(PAA) and 2-phosphonobutane-1,2,4-tricarboxylic acid (PBTCA) has been studied in a pool boiling system.It is found that PBTCA has a better inhibition effect than PAA under the identical conditions.X-ray diffraction (XRD) and Fourier transform-infrared(FTIR) analyses demonstrate that the content of vaterite increases as inhibition effects increase.The metastable crystal froms of vaterite and aragonite are stabilized kinetically in the presence of inhibitors.The relationship between the inhibition effect and the fractal dimension has also been investigated.The result shows that the fractal dimension is higher in the presence of inhibitors.The better the inhibition efect,the higher the fractal dimension.The step morphology was observed by atomic force microscopy(AFM) images.It is shown that the step space on the calcium carbonate surface increases in the presence of inhibitors.Moreover,with the increase of inhibition effect,both the step space and the fractal dimension increase.The step bunching is found on the calcium carbonate by AFM.The better the inhibition effect of the inhibitor,the slower the step velocity in the unbunched location.As a result,the step space becomes wider in the presence of PBCA than that in the presence of PAA.     

AI_4C_3 Hydration Thermochemical Analysis for Burned Carbon-containing Refractories with Al

In this paper, X-ray diffractogram analysis and SEM observation of Al$ C$ formed at high temperature from carbon-containing refractories ivith Al have been carried out. Aluminum added to carbon-containing refractories reacts with C(s) to form Al^ C^(s) gradually during heating from 600 'C to 1200^0 . It is considered that the interlocked structure of Al^ C-$ plate crystals promotes the outstanding increase of hot modulus of rupture of carbon-containing refractories with Al. The HMOR of carbon-containing refractories added with Al additive from 0 to 5wt% increases by 2.8 times being from 6.5MPa to 18.2MPa. After a thermochemical calculation for hydration reaction processes ofAl^C^ and H^O (g), the equilibrium partial pressure chart ofH^O (g) in H^O-A^C^-Al^ OH)} system vs various temperatures has been attained . The H2 0 (g) partial pressure in the air needed for the Al^ C3 hydration reaction is no more than 10 ~ 18 atm at the temperature below 120t . It is considered that the burned carbon-containing re     

循环过程中陶瓷滤材内粉尘沉积规律实验研究

The penetration and deposit of particles within the medium is thought to be one reason that the residual pressure drop of the rigid ceramic filter increase with cycle number. In this study, the change in the microstructure of a single layer ceramic filter candle during filtration-cleaning cycle was observed by scanning electron microscope (SEM) and the resistance property of the filter was monitored accordingly. The experimental results show that there exists a serious dust deposit within the filter medium, especially at the surface region. This should be responsible for the decrease of the filter permeability. The deposit law of dust in the filter medium during filtration-cleaning cycle was then studied by measuring the deposit depth, the deposit amount, the particles distribution within the medium, the size distribution of deposited particles, and so on. Particles migration and fine particles penetration were found to be the main reasons, for which dust deposit within the filter medium became aggravated with cycle number. Based on a differential form of Ergun equation, an expression for the pressure drop of a used ceramic filter was developed with a good agreement with experimental results. Then, the effect of dust deposit on the residual pressure drop was studied at the different face velocities and dust sizes. It was found that face velocity and dust size significantly influence dust deposit within filter medium, and then the operation performance of the filter.     

Blue light emission in mesoporous SiOx nano-structure

Mesoporous silicon oxide (SiO_x) nano-structure has been synthesized from tetraethyl orthosilicate (TEOS) with a two-step method: sol–gel with the hydrolysis of TEOS and solvent-thermal process. Observations using scanning electron microscopy (SEM) and transmission electron microscopy (TEM) show that the mesoporous nano-materials are sponge-like and meshes of them have a uniform diameter of about 15 nm. High-resolution transmission electron microscopy (HRTEM) reveals that the sample has two states: crystal silicon and amorphous SiO_x. Energy dispersed X-ray spectrometry (EDAX) indicates that this structure is composed of Si and O elements and atomic ratio of Si:O is about 1:1.4. The photoluminescence (PL) measurements were carried out and show that the SiO_x mesoporous structure has a stable and intensive blue emission. This nano-structure may have potential applications in future integrated optical devices.     

Ni-ZrO2复合镀层的结构表征

采用复合电沉积制备Ni-ZrO2复合层。采用X-射线衍射检测ZrO2的加入对镍镀层结构的影响,如衍射峰的强度、金属电沉积时晶粒的择优取向。测试表明,Ni和ZrO2各自在特定的角度分别出现其独特的衍射特征峰,互不干扰,镀层中ZrO2含量增高,衍射强度变强。ZrO2在镀层的掺杂,镀层的晶粒尺寸由29.29 nm降至21.78 nm,镀层晶粒细化。     

High-purity fibrous carbon deposit on the anode surface in hydrogen DC arc-discharge

A brittle porous deposit consisting of high-purity fibrous carbon products with a diameter of 25-100 nm was obtained on a heated anode surface in hydrogen DC arc-discharge. Hydrogen arc plasma was generated between a graphite cathode and a carbon/metal composite anode consisting of 1.0 at.% Fe, 0.6 at.% Co, 2.4 at.% Ni, and 0.4 at.% FeS. X-ray diffraction analysis revealed that the fibrous products had a turbostratic carbon structure, with an interlayer spacing of 0.346 nm. Elemental analysis showed that the fibrous products were composed of 98.4 mass% of carbon. Three types of nano-structured fibrous products were observed using transmission electron microscopy, (1) with a bamboo structure, (2) with a hollow core, and (3) without a hollow core. The formation of fibrous products was initiated by arc-generated metal particles with a diameter of 5-75 nm, then carbon for further growth was supplied by the decomposition of polycyclic aromatic hydrocarbons that were created by interactions between arc-generated carbon clusters and atomic hydrogen. The nano-structure of the fibrous products is thought to depend on the size and morphology of the catalytic metal particles. The synthesis conditions, microstructural characterization and the growth mechanism of the fibrous carbon products are reported.     

Sonochemical Synthesis of a New Lead(II) Coordination Polymer with 2-Quinoline Carboxylate Ligand: A Precursor for the Preparation of Nano-structured Lead(II) Oxide

Crystalline and nano-structure of a new Pb(II) coordination polymer, [Pb(NO₂)(2-quc)]_n (1), {Hquc?=?2-quinoline carboxylic acid} is synthesized via heat gradient and sonochemical methods, respectively. The newly synthesized structures are characterized by scanning electron microscopy (SEM), X- ray powder diffraction (XRD), IR and ¹HNMR spectroscopies, elemental analyses and single crystal X-ray diffraction is used to understand the exact structure of the crystalline 1. Thermal stability of nano and bulk samples of compound 1 are studied and compared through thermal gravimetric and differential thermal analyses. PbO nanoparticles are then produced by calcination of the nano-structure of compound 1 at 600?°C. The obtained PbO is characterized by XRD and SEM analyses.     

Ni-W镀层的非晶化机制

用电沉积法制备Ni－W非晶态镀层。随着镀层中钨含量的增加，Ni－W合金镀层结构由晶态向非晶态转变。x射线光电子能谱分析结果表明，Ni－W非晶态镀层中Ni、W均以零价态形式存在，没有形成金属间化合物。     

Direct Synthesis of PbO Nanoparticles from a Lead(II) Nanoflower Coordination Polymer Precursor: Synthesis, Crystal Structure and DFT Calculations of [Pb(pcih)N3H2O] n with the Terminal Azide Unit

The first nanoflower lead(II) coordination compound, [Pb(pcih)N₃MeOH] _n (1), (“pcih” is the abbreviations of 2-pyridinecarbaldehyde isonicotinoylhy-drazoneate) were synthesized by a sonochemical method. The new nano-structure was characterized by transmission electron microscopy, scanning electron microscopy, X-ray powder diffraction, elemental analyses and IR spectroscopy. Single crystalline material was obtained using a heat gradient applied to a solution of the reagents. Compound 1 was structurally characterized by single crystal X-ray diffraction. The determination of the structure by single crystal X-ray crystallography showed that the complex taking the form of a zig-zag one dimensional polymer in the solid state and the coordination number of PbII ions is six, (PbN₄O₂), with three N-donor and one O-donor atoms from two “pcih” and one O-donors from methanol and one N atom from terminal azide anion. It has an asymmetrical coordination sphere. The supramolecular features in these complexes are guided and controlled by weak directional intermolecular interactions. The chains interact with each other through π–π stacking interactions creating a 3D framework. After thermolysis of 1 at 180 °C with oleic acid, pure phase nano-sized lead(II) oxide was produced. The morphology and size of the prepared PbO samples were further observed using SEM.     

Sonochemical Synthesis of Two New Nano-structured Cadmium(II) Supramolecular Complexes

Nano-particles of two new Cd(II) supramolecular complexes, [Cd(4,4-di-tert-bubipy)Cl₂(DMSO)] (1) and [CdI₂(4,4′-dmbpy)(DMSO)] (2) have been synthesized by sonochemical process and characterized by scanning electron microscopy, X-ray powder diffraction, IR spectroscopy and elemental analyses. The structure of compound 1 has been characterized by single crystal X-ray diffraction. The prepared nano-structure was characterized by scanning electron microscopy and X-ray powder diffraction. The nano-structures of supramolecular complexes have been synthesized with calcination of complexes at oleic acid as a surfactant at 190 ºC too. The size of the samples prepared by sonochemical method and calcination are about 30–40 and 40–50 nm respectively.     

烧结法制备含低水溶钾的六钛酸钾晶须

研究了烧结法制备的六钛酸钾晶须（PTW）中的水溶钾.实验发现：水溶钾并不是来自PTW晶体的溶解;水溶钾溶出很缓慢;悬浮液pH值随水溶钾含量增加而升高.根据实验现象,从PTW生长机理分析认为PTW表面纳米缝隙中存在的微量K₂O导致水溶钾的产生.将烧结法制备的PTW在pH=4.5的溶液中浸泡8 h以上或者超声波清洗,可以获得水溶钾含量少于0.1‰（质量）,且满足复合材料使用要求的PTW.硅烷偶联剂(A186) 改性PTW不影响水溶钾析出,而无机包裹(SiO₂) PTW水溶钾析出减少.     

掺钕钨酸钆钠晶体生长、结构及光谱特性

采用提拉法生长了尺寸为φ(30～35)mm×80mm的掺钕钨酸钆钠[Nd:NaGd(WO4)2,Nd:NGW]晶体。生长Nd:NGW晶体的最佳工艺参数为:晶体的提拉速率为1～2mm/h,晶体转速为15～18r/min,冷却速率为10℃/h,液面上轴向温度梯度为0.7～1℃/mm。通过热重-差热分析(thermogravimetry-differential thermal analysis,TG-DTA),X射线衍射(X-ray diffraction,XRD)对晶体进行表征。测试了晶体的红外及Raman光谱,分析了晶体的振动模式,并将晶体振动光谱进行归属。由TG-DTA曲线得到晶体熔点为1251.7℃。XRD分析表明:晶体属于四方晶系、白钨矿结构、I41/a空间群,晶胞参数a=0.53213nm,c=1.13070nm。吸收光谱表明:Nd:NGW晶体在805nm附近有较强、较宽的吸收峰,吸收截面积为3.581×10-20cm2,适合于激光二极管泵浦。     

Characterisation of CoNi(Cu)/Cu multilayers deposited from a citrate electrolyte in a flow channel cell

CoNi(Cu)/Cu multilayers consisting of 50 and 200 bi-layers were deposited from a citrate electrolyte in a flow channel cell by a dual pulse plating technique. The dissolution of the ferromagnetic components during pulse plating was studied using an oscilloscope and cyclic voltammetry. It was found that the dissolution was suppressed due to the passivation of the ferromagnetic layers before the deposition of an atomic layer of nonmagnetic component on them. The passivation was a function of the nickel ion concentration in the electrolyte. X-ray studies showed that the deposit had a preferred crystal orientation of [1 1 1] and suggested the formation of a super-lattice. Atomic force microscopy studies showed a four-fold increase of the roughness of the ferromagnetic surface with increasing layer thickness from 6 to 10 nm, whereas the roughness of the nonmagnetic surface only changed slightly with increasing layer thickness. The multilayers exhibit giant magnetoresistance.