Micromagnetic simulation of FeCo write head in perpendicular recording hard disk drives

The single-pole tip (SPT) heads made of the high saturation FeCo ferromagnetic metals are crucial for the actualization of ultrahigh density perpendicular recording. The effective head field distribution in the medium is of key importance for the design of the SPT head, which would be analyzed by micromagnetic simulations in this work. Two 3D micromagnetic models of the SPT head were established to select a more appropriate method of modeling, with a magnetostatic image effect or a real soft magnetic material to model the image of the SPT head in soft under layer (SUL). The results from these two designs were tested and compared to the ideal head field calculated by the Jacobi finite element method (FEM); and the design with the real soft magnetic material as image was proved suitable for simulating the ultrahigh density perpendicular recording write head.     

HRP-12型负载杂多酸催化剂的失活原因及预防措施

采用XRD、NMR、IR、MS等手段对长链烷基苯合成中失活负载型杂多酸催化剂进行了表征,结果表明,催化剂的失活主要是由于表面结焦引起的,原料中的双烯、烷基芳烃杂质以及反应生成的副产物重烷基苯是引起催化剂结焦的主要原因,对原料进行脱双烯和脱芳烃精制、提高苯烯比以及用苯洗涤催化剂等措施能够有效抑制催化剂的失活。     

Improving Information Quality Through it Alignment Planning: A Case Study

This article describes how a medium-sized, Midwestern power company implemented an IT alignment planning process. the IT alignment planning process was a successful four-year activity that involved, first, a pilot implementation and then a companywide implementation of the IT alignment planning process. Designed to be flexible and to dovetail with corporate strategic planning processes, IT alignment planning achieved acknowledgment and approval in all divisions of the company. the IT alignment planning process improved and facilitated communication on IT and IT projects throughout the company, from the executive level to the operational level, and brought the IT and client units closer together.     

Geotechnical Investigation Strategies for Lunar Base

Geotechnical characterization of potential lunar sites will be a critical part of the planning and design process. The strategies used to conduct a geotechnical investigation will be dictated by the specific needs of the lunar base, the unique environment of the lunar surface, and general character of the lunar soils and rocks. This paper outlines some of the types of geotechnical information that will be important and identifies some of the more promising strategies which might be used to obtain such information in the lunar environment. Some of the most important geotechnical information for planning and site development will be related to construction in the lunar soil. In addition to construction concerns, geotechnical data for foundation design (or verification of predesigned foundations) will be needed. The geotechnical site‐characterization work should include geophysical techniques, supplemented by conventional mechanical boring and testing only to the degree necessary to correlate geophysical measurements with conventional soil properties and to investigate anomalies. Equipment used for geotechnical site characterization will also serve for mineralogical exploration. Several techniques for geotechnical investigation that may provide very useful information in an expedient manner are described. Geophysical methods include seismic and electromagnetic methods, including seismic surveys that utilize surface waves. Electromagnetic methods such as ground‐penetrating radar are fast, efficient methods for mapping the subsurface, although these techniques do not measure soil characteristics that can readily be correlated with engineering properties. Seismic methods provide information that may correlate with soil strength, compressibility, and excavatability. In‐situ physical testing will likely include penetration testing for direct physical measurement of lunar soil behavior.     

A Study of AlN Films Prepared by Arc Ion Plating

Hexagonal AlN films have been obtained by arc ion plating at different negative biases ,X-ray diffraction and scanning electron microscopy results show that AlN films with smooth surfaces and (002) preferred orientation are obtained at low biases ,whereas those with coarse surfaces and (100) preferred orientation are obtained at high biases,The formation mechanism of AlN is analyzed and the experiment results are discussed,The effect of bias on adhesion strength has also been examined.     

轧后穿水冷却工艺对棒材组织性能的影响

针对轧机产量提高后冷床冷却能力不足的问题 ,研制开发了棒材轧后穿水冷却技术。通过对小规格 2 0MnSiV热轧带肋钢筋进行轧后穿水冷却 ,钢材上冷床温度降低了 90～ 110℃ ,提高了产品质量 ,改善了各项力学性能 ,抗拉强度平均提高了 3 5～ 40MPa ,钢材性能合格率由 97.5 %提高到了 99.6% ,解决了冷床冷却能力不足、制约生产的瓶颈问题。     

再制干酪的研究

本实验以车达干酪、高达干酪为原料干酪，添加选取85～87℃，6、5～7min的融化条件。研究选择不同成熟期、不同种类的原料干酪和添加不同比例及种类的溶解盐对干酪组织状态、风味的影响。     

Architectures for Silicon Nanoelectronics and Beyond

Although nanoelectronics won't replace CMOS for some time, research is needed now to develop the architectures, methods, and tools to maximally leverage nanoscale devices and terascale capacity. Addressing the complementary architectural and system issues involved requires greater collaboration at all levels. The effective use of nanotechnology calls for total system solutions     

Novel blood-compatible waterborne polyurethane using chitosan as an extender

A series of novel block polymers of polyurethane (PU) and chitosan have been prepared in two steps. The first step is the preparation of PU prepolymer, obtained from polytetramethylene oxide glycol (PTMO, M_n = 1000), isophrone diisocyanate (IPDI), and 2,2′-dimethylol propionic acid (DMPA), followed by ionizing PU prepolymer with triethylamine (TEA). The second step involves PU chain-extended by water-soluble chitosan of low molecular weight (M_n = 5000) by self-emulsion polymerization method. The sizes of the latex particles, morphology, and copolymer architecture have been characterized by dynamic light scattering (DLS), general tensile test, infrared spectroscopy (IR), surface contact angle measurement, and transmission electron microscopy (TEM). Furthermore, it shows that the addition of chitosan remarkably increases anticoagulative property of PU elastomers confirmed by the recalcification time. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008