以表面负载季铵盐阳离子型苯/丙乳胶粒为模板制备ZrO_2空心微球

以C9油与甲基丙烯酰氧乙基三甲基氯化胺的共聚物P(C9-DMC)为乳化剂制备苯/丙阳离子乳胶粒,并以其为模板,利用直接包覆法制备了由17 nm左右微晶体堆成的ZrO2空心微球。所制得的样品采用FT-IR、XRD、TEM和SEM等进行了表征。     

S盒设计中的一种新准则

本文提出了强扩散准则,强雪崩效应以及扩散效应的逼近优势等相关概念,给出了差分均匀性与强k阶扩散准则之间的相互关系,利用给出的设计准则改进了Rijndael密码的S盒。     

煤焦油市场现状及后期趋势

一、煤焦油市场现状 原油期货价格于7月4日创历史新高，盘中达146．69美元／桶，加之全国煤炭市场价格暴涨300元／吨，以及绿色奥运的来临，在多重内外因素的叠加效应下，煤焦油市场价格出现了一波大幅上涨行情，同时也创下煤焦油价格的历史新高。全国煤焦油市场状况、地域性特征十分明显，按地理划分为四类市场。     

混凝土小型空心砌块保温体系

针对不同类型、不同结构形式建筑的节能需求,合理选择自保温墙体材料,可达到节能与经济性的统一,本文介绍三种混凝土小型空心砌块建筑节能保温体系.     

废铜的分类

一、一次废铜 如不合规格的阳极、阴极和坯料,阳极废品.这些废料不能进行深加工或出售,通常是将其返回上一步工序,不合规格的铜通常重新返回转炉或阳极炉进行电(解)精炼,有缺陷的坯料则进行重熔和重铸.     

Analysis of S-SEED''s characteristics in optical switch

This article introduces the basic structure of a symmetric self-electrooptic effect device （S-SEED）, and applies the Kirchoff＇ s current law and a purely equivalent capacitive model, to analyze S-SEED＇s switch characteristics. Linear approximation and N-segment approximation are utilized to obtain S-SEED＇s voltage-time （V-T） and characteristics. Theoretical analysis is verified by simulations, and the results demonstrate that the precision of S-SEED＇s switch time can satisfy the requirement in applications with linear approximation. Moreover, the simulations compare S-SEED＇s switch characteristics with different input powers and input contrast ratios, which reveal that increasing input contrast ratio is an effective way to improve S-SEED＇s switch characteristics.     

浅谈光缆生产中的吹干方式与能效利用

针对光缆生产中对光纤套管、填充绳及护套生产工序频繁使用的吹干工艺要求，大流量的压缩空气在能效不充分的利用中流失问题，探讨对吹干器的工作原理和改进方案，以及生产中的效果和能耗的控制。     

薯秧倒栽增产

笔者在同等条件下试验对比薯秧倒栽比顺栽可提高产量1倍以上。倒栽的薯苗比顺栽的生长缓慢．约需7天时间叶腋间长出新芽，以后慢慢形成主茎，由于茎中输导组织输送根部吸收的水分及有机养料的方向逆转．其输送速度减慢．     

Spin Dependent Hopping in Ti Doped La0.67 Ca0.33 MnO3

A systematic investigation of the magnetic and transport properties of Ti doped La0.67Ca0.33MnO3 was reported. The Ti substitution for Mn ions results in a reduction in ferromagnetism and conductivity. The metal-insulator transition temperature is close to Curie temperature which decreases from 274 to 82 K as x increases from 0 to 0.17. The most important effect of Ti doping is to introduce spin clusters in the samples due to the distortion of local lattice and the inhomogeneous magnetic structure induced primarily by the random distribution of Mn ions. A maximum magnetoresistance ratio as large as 90% in 1 T at 122 K was obtained for the sample with x =0. 055, which is four times larger than that obtained for LCMO sample at 272 K. There is a remarkable field-history dependent MR in the cooling process for the doped samples while such phenomenon disappears in the warming run. The resistivity follows well the variable range hopping behavior in paramagnetic state. Both the size effect and spin dependent hopping of carriers between the spin clusters should be considered in this system.