Al_2O_3陶瓷表面化学气相沉积Ni涂层及其与Cu润湿性

将NiCl2·6H2O经过脱水干燥后得到的NiCl2粉末作为原料,采用化学气相沉积技术通过H2还原反应,在Al2O3陶瓷表面沉积了Ni涂层。研究了涂层的相组成、涂层与Al2O3陶瓷结合力和涂层与铜熔液间的润湿行为。结果表明:制备的涂层中的主要组分为Ni,Ni涂层均匀、致密,厚度可达40μm,且涂层与陶瓷之间的结合良好。座滴法测得沉积Ni涂层的Al2O3陶瓷与Cu之间的润湿角为30.15°,表明涂层明显改善了陶瓷与金属间的润湿性。     

Sn-Zn, Sn-Ag-Cu和Sn-Bi-Cu无铅焊锡合金与铜的润湿性

采用静滴法对Sn-Zn, Sn-Ag-Cu, Sn-Bi-Cu锡基合金在铜基板上的润湿性进行了研究. 结果表明,Sn-Bi-Cu合金的润湿性良好,Sn-30Bi-0.5Cu合金在530 K时的接触角为26o,熔融的Sn-3Ag-0.5Cu共晶合金的接触角几乎不存在滞后性. 锡基合金中添加Bi元素可提高合金的润湿性,添加Cu元素可有效防止溶铜发生. 研究结果为无铅焊锡合金的应用提供了一定的理论依据.     

改性沸石对废水中Cu2+、Cr3+的去除作用研究

用Na OH碱熔-水热法处理得到的改性斜发沸石作为吸附交换剂,对模拟废水中以Cu2+、Cr3+为代表的重金属离子进行吸附处理。研究了不同吸附时间、投加量以及初始浓度条件下,改性斜发沸石对Cu2+、Cr3+的去除效果。实验结果表明:改性沸石与水样中Cu2+、Cr3+的质量比分别为18.75∶1、13.33∶1时,对Cu2+、Cr3+的去除率分别达88.0%、87.4%,且为快速吸附平衡过程。此外,用Na Cl溶液和Na Cl溶液加氨水对吸附Cu2+饱和的改性沸石进行再生实验,再生率较高,改性斜发沸石可以多次重复利用。     

甲醇氧化重整催化剂的研究

制备并优选了甲醇氧化重整的催化剂 ,实验表明在相同的温度下 ,Pd催化剂、Cr2 O3 ZnO氧化物催化剂和Cu催化剂相比 ,活性、选择性以及氢产率都表现为Cu >Cr Zn >Pd。其中 ,Cu催化剂在低温时、Cr Zn催化剂在高温下表现出良好的活性和选择性 ,而且Cr Zn催化剂的热稳定性较好     

Cu2＋、Zn2＋对玻璃弹簧负载型P／TiO2光催化还原Cr（Ⅵ）的影响研究

金属铬[Cr（Ⅵ）]是一种很常见的重金属污染物,在电镀、冶金、化工等一些加工行业废水中含量很大。Cr（Ⅵ）具有很强的致癌性和毒性,消除水体中Cr（Ⅵ）污染的研究具有重要的意义。本实验在低温条件下用双氧水制备了P／TiO2溶胶,并将其负载于玻璃弹簧上,形成负载型P／TiO2光催化剂。在紫外光照下,该催化剂光催化还原Cu2＋和Cr（Ⅵ）共存溶液或Zn2＋和Cr（Ⅵ）共存溶液中的Cr（V1）时,随着Cu2＋或Zn2＋浓度的增大Cr（Ⅵ）的还原率先增加后下降;在Cu2＋浓度为O．004mol／L时或Zn2＋浓度为O．0025mol／L时,Cr（VI）的还原率最高。     

微电解-中和沉淀法处理含Cr^6＋与Cu^2＋电镀废水的试验研究

采用微电解-中和沉淀法处理含Cr6＋与Cu2＋电镀废水,探明pH与初始浓度对处理效果的影响。结果表明：用微电解法与碱液中和沉淀处理含Cr6＋与Cu2＋电镀废水去除率高,在质量浓度低于100 mg/L的情况下,处理后废水的Cr6＋与Cu2＋均可达GB8978-96《污水综合排放标准》中的一级排放标准,具有较好的工业应用前...     

用亚甲基蓝吸附法测量油层岩石的润湿性

储层岩石润湿性影响油、水在储层中的分布，对原油开采过程均具有至关重要的作用。测量储层岩石润湿性的标准方法（Amott and US-BM法）属于经验方法，包括在润湿相和非润湿相共存时让油、水两相相互驱替。测量结果可能与流体的饱和度和实验过程有关，而产生某些不确定性。本文提出根据亚甲基蓝在储层岩石表面的吸附面积分数，测量固体表面的润湿性。该法具有一定的理依据，测量结果不受流体的饱和度和实验过程的影响。     

热管理用金刚石/Cu复合材料的研究进展

金刚石/Cu复合材料具有高导热、低热膨胀系数、密度低等优点,与新一代芯片、电子系统具有良好的匹配性,在热管理材料行业具有良好的应用前景,但是其金刚石与Cu的表面润湿性较差,复合材料的一些热学性能甚至低于单相材料的热学性能。对目前金刚石/Cu复合材料的制备手段、改性方法进行总结,并对仍存在的问题提出了解决方向,希望对相关研究人员提供研究方向上的帮助。     

石墨快速消解法结合电感耦合等离子体发射光谱仪测定水泥熟料中多种重金属元素

建立了石墨快速消解法结合电感耦合等离子体原子发射光谱仪(ICP-AES)测定水泥熟料中Cr、Mn、Ni、Cu、Zn的定量分析方法。选择267.716 nm、257.610 nm、231.604 nm、324.754 nm、213.856 nm分别作为Cr、Mn、Ni、Cu、Zn的分析谱线,无需进行光谱干扰校正。对水泥熟料实际样品分别采用微波消解法和石墨快速消解法进行消解,并用ICP-AES测定其中重金属含量,发现测试结果一致。精密度实验RSD均小于4%,表明该方法能满足日常对水泥熟料中Cr、Mn、Ni、Cu、Zn的快速检测要求。     

城市污泥堆肥过程中重金属形态变化研究

重金属是城市污泥堆肥利用的重要限制因素。为了解决城市污泥的处理与处置难题,本研究以啤酒厂污泥和污水处理厂的污泥的混合污泥作为实验原料,通过原子吸收方法测定堆肥化过程不同阶段重金属Pb、Cu、Zn、Cr的形态变化。结果表明,污泥堆肥化过程中对重金属Zn的有效态含量影响不显著,对Cu、Pb、Cr向有效态转变具有一定的促进作用;堆肥化过程可显著降低交换态Zn对植物的污染;重金属Zn、Cu的总含量变化均呈逐渐降低的趋势,表明堆肥化过程有利于降低重金属的含量。     

Wetting of AlN and TiC by Liquid Ag and Liquid Cu

The wetting of AlN and TiC by liquid Ag and liquid Cu was investigated by the sessile drop technique at 10⁻⁶ torr or less. An empirical relation was established between the cosine of the contact angle and the temperature or surface tension of the liquid drop. The critical surface tension for spreading and its physical significance are discussed. A method for estimating the surface energies of ceramics is proposed. The surface tension of TiC is estimated to be 1242±158 dynes/cm and that of AlN 990±110 dynes/cm. The surface tension of liquid Ag followed the equation γ _Lv (Ag) (dynes/cm) = 1092–0.14T (°C) and that of liquid Cu γ _LV (Cu) (dynes/cm) = 1462–0.27T (°C).     

A CRITICAL REVIEW: SURFACE AND INTERFACIAL TENSION MEASUREMENT BY THE DROP WEIGHT METHOD

The drop weight method has been used as a standard method for surface and interfacial tension measurement. However, lack of appropriate guidelines in using this method has resulted in errors. The specific objective of this critical review is to present the experimental setup, the limitations on the correction factors, and the principle of the drop weight method. Mathematical models of correction factors were evaluated by using a proposed error analysis. The use of the proposed Lee-Chan-Pogaku model and HG-Equation 2 for correction factor determination is suggested. However, further investigations would be required to justify the validity of the correction factors at low r/V^1/3 range and their use for viscous fluids. The physics of drop detachment is complicated; more investigations would be required to form a rigid theory of this method.     

Wetting of TaC by Liquid Cu and Liquid Ag

Wetting of TaC^0.97±0.01 by liquid Cu and liquid Ag was studied by the sessile drop method. The cosine of the contact angle increased linearly with increasing temperature in both systems. The critical surface energy for spreading was 1098 ergs/cm² at 1605°C for Cu and 688 ergs/cm² at 2160°C for Ag. The work of adhesion, which was 1759 ergs/cm² at the melting point for Cu and 321 ergs/cm² at the melting point for Ag, increased parabolically with increasing temperature in both systems. The surface energy of TaC_0.97±0.01 was estimated to be 1804±706 ergs/cm².     

SURFACE PROPERTIES OF FUSED SALTS AND GLASSES: II, CONTACT ANGLE AND WORK OF ADHESION ON GOLD AND PLÁTINUM IN VARIOUS ATMOSPHERES

An apparatus is described which allows measurements to be made of the contact angle and the exact dimensions of a sessile drop of liquid resting on an electrode graphite surface in vacua or in nitrogen atmosphere. Temperatures up to 1100°C have been employed. Under these conditions, surface tension and gravity are the only forces acting on the drop, and the exact shape, surface, and volume may be computed from the tables of Bashforth and Adams. The method may be used with liquids having viscosities up to 600 poises, whereas the bubble-pressure method used by Jaeger is limited to liquids of viscosity less than 70 poises. On the basis of internal evidence, the surface-tension values obtained by the sessile-drop method are considered correct within 5%. They also agree with data by Jaeger, but are, roughly, twice as great as those of Washburn and Libmart, who used a ring method. The probable error in Washburn and Libman's work appears to be in their assumption of zero contact angle.     

浅谈整流机组的均流及其检测与调整

分析了对整流机组均流程度进行检测与调整的必要性。介绍了衡量均流程度的均流系数K及其计算方法,提出了简便易行且安全可靠的快熔元件压降检测调整法。     

A CRITICAL REVIEW: SURFACE AND INTERFACIAL TENSION MEASUREMENT BY THE DROP WEIGHT METHOD

The drop weight method has been used as a standard method for surface and interfacial tension measurement. However, lack of appropriate guidelines in using this method has resulted in errors. The specific objective of this critical review is to present the experimental setup, the limitations on the correction factors, and the principle of the drop weight method. Mathematical models of correction factors were evaluated by using a proposed error analysis. The use of the proposed Lee-Chan-Pogaku model and HG-Equation 2 for correction factor determination is suggested. However, further investigations would be required to justify the validity of the correction factors at low r/V ^1/3 range and their use for viscous fluids. The physics of drop detachment is complicated; more investigations would be required to form a rigid theory of this method.     

Contact Interaction and Wetting of Strontium Fluoride by Metal Melts

Abstract

The wetting of SrF₂ by pure metals and Cu–Ti (Zr) and Ni–Ti (Zr) alloys by the sessile drop method in vacuum (1 × 10^?3 Pa) was studied. Ga, In, Sn, Pb, Al, Cu, Ag, Au do not wet SrF₂ in the temperature range from melting point up to 1250°C. The phenomenon of dewetting of SrF₂ by Al and Ti-containing binary alloys at temperatures higher than 1100°C is observed.     

铜银改性六方介孔硅材料的结构及抗菌性能

采用溶胶-凝胶法,合成了铜银改性的六方介孔二氢化硅(hexagonal mesoporous silica,HMS)无机抗菌材料,通过X射线衍射、顺磁共振、紫 外漫反射、Fourier红外、热重-差热分析、环境扫描电镜、电子能谱及N2的吸附-脱附技术对材料结构进行了表征,并以大肠杆菌、金黄色葡萄球菌、枯草杆菌及芽孢杆菌为实验对象考察了材料的抗菌性能.结果表明:铜、银已引入HMS载体的骨架,材料的介孔结构、孔径、粒子形貌等也发生了明显变化,脱模的热化学过程大大缩短,对紫外-可见光吸收明显增强;抗菌实验显示材料抗菌惟能良好.对枯草杆菌及芽孢杆菌的抗菌效果最佳,铜银原位改性HMS的用量为1.00g/L,12h后即可将两者彻底杀灭.     

Multiscale Simulation of Indentation,Retraction and Fracture Processes of Nanocontact

The process of nanocontact including indentation and retraction between a large Ni tip and a Cu substrate is investigated using quasicontinuum (QC) method. The multiscale model reveals that significant plastic deformation occurs during the process of nanocontact between Ni tip and Cu substrate. Plastic deformation is observed in an area as large as 20 nm wide and 10 nm thick beneath Ni tip during the indentation and retraction. Also, plastic deformation at a deep position in the Cu substrate does not disappear after the neck failure. The analysis of generalized planar fault energy curve shows that there is a strong tendency for deformation twinning in Cu substrate. However, deformation twinning will be retarded during indentation due to the high stress intensity caused by stepped surface of Ni tip. The abrupt drop of load curve during tip retraction is attributed to the two different fracture mechanisms. One is atomic rearrangement near the interface of Ni tip and Cu substrate at the initial stage of neck fracture, the other is shear behavior of adjacent {111} planes at the necking point. A comparison of the critical load and critical contact radius for neck fracture is also made between theoretical values and our numerical results.     

GENERALIZED EQUATION FOR AIRFLOW RESISTANCE OF BULK GRAINS WITH VARIABLE DENSITY, MOISTURE CONTENT AND FINES

The pressure drop versus airflow data for several types of grains were compiled and a grain specific generalized pressure drop versus airflow equation was developed. The equation predicted pressure drop as a function of airflow when porosity, moisture content and fine concentration were specified. The effect of properties of airflow on the resistance of bulk grain to airflow was also considered in the generalized equation. A modified Leva's equation was developed. The similarity between the grain specific equation and the modified Leva's equation led to a method for estimating the shape factor for irregularly shaped particles.