模拟深海压力对2种低合金钢腐蚀行为的影响

通过腐蚀失重、电化学测试、锈层分析和微观形貌观察研究了海水压力对不同成分2种低合金钢(X和Y)腐蚀行为的影响.结果表明,X钢更易受到海水压力的影响而被加速腐蚀.深海压力均加速了2种低合金钢的阳极溶解速度;压力对于X钢的氧扩散还原过程影响很小,而海水压力的增加导致Y钢阴极电流密度降低的原因是腐蚀产物直接参与了阴极还原反应...     

杂质Fe对A1-Zn-In牺牲阳极性能的影响

炼制Fe杂质含量不同的6种Al-Zn-In阳极,采用恒电流方去评价了其电化学性能,并通过扫描电镜观察其溶解的微观形貌,探讨了Fe杂质含量对阳极电化学性能的影响规律与机制.结果表明,随着Fe杂质含量的升高,Al-Zn-In阳极的电流效率呈先增加后降低趋势,原因足少量的Fe可增加阳极的活化点,而过量的Fe则作为阴极相引发电偶腐蚀使得阳极呈局部腐蚀溶解.     

射流管电液伺服阀专题讲座

第四章伺服比例阀的发展 1 伺服阀与比例阀简介 电液伺服阀是在二战期间由于飞行器等军事装备对控制系统快速性动态精度的更高要求而发展起来的,并在战后逐渐用于民用和工业设备.它是一种接受模拟量电控制信号,输出随电控信号大小和极性变化、且快速响应的模拟量流量和(或)压力的液压控制阀.根据其液压放大器的不同,主要分为喷嘴挡板式伺服阀和射流管式伺服阀[1].电液伺服阀具有体积小、功率放大率高、直线性好、响应速度快、运动平稳可靠、能适应模拟量和数字量调节等优点,在各种电液伺服系统中得到特别的重视.     

方向性滤波去噪方法及其应用

目前的地震资料去噪方法多为对逐道的地震数据进行去噪处理,未考虑构造或层序方面的信息,方向性滤波去噪方法的不同之处在于它是沿着地震数据的同相轴方向进行滤波,可以更加有效地提高地震信号的信噪比,并增强地震同相轴的连续性.方向性滤波去噪方法是通过梯度结构张量估计地震同相轴的方向信息,根据这些方向信息进行方向性滤波器的设计,并将该滤波器应用于地震数据进行滤波.模型检验及实际应用表明,方向性滤波去噪方法不仅提高了原始地震数据的信噪比,还保持了原始信号的分辨率,方向性滤波去噪处理的地震资料仅在低频和高频部分的能量略有降低,并未降低原始信号的主频,为进一步的地震解释性处理提供高信噪比、高分辨率的地震数据,具有广阔的实际应用价值.     

Functional analysis of ZNF85 KRAB zinc finger protein, a member of the highly homologous ZNF91 family

We previously identified the ZNF85 (HPF4) KRAB zinc finger gene, a member of the human ZNF91 family. Here, we show that the ZNF85 gene is highly expressed in normal adult testis, in seminomas, and in the NT2/D1 teratocarcinoma cell line. Immunocytochemical localization of a panel of beta-Gal/ZNF85 fusion proteins revealed that ZNF85 contains at least one nuclear localization signal located in the spacer region connecting the KRAB domain with the zinc finger repeats. Bacterially expressed ZNF85 zinc finger domain bound strongly and exclusively to DNA in vitro in a zinc-dependent manner. The KRAB(A) domain of the ZNF85 protein and of several other members of the ZNF91 family exhibited repressing activity when tested in Gal4 fusion protein assays. The repression was significantly enhanced by the addition of the KRAB (B) domain, whereas further addition of other conserved regions had no effect. The ZNF85 KRAB(A) and (B) domains in vitro bound several nuclear proteins that might constitute critical cofactors for repression.     

DYNAMICS OF THE ZONAL ASYMMETRIC STRUCTURE OF ARCTIC OSCILLATION

The Arctic Oscillation (AO), though basically is a zonal symmetric phenomenon, also shows zonal asymmetric variation. The dynamics of this zonal variation is considered here from the point of view of the planetary propagation on the earth sphere. Based on the linear barotropic vorticity equation, the planetary wave ray path is calculated in the winter January. It shows that NAO(North Atlantic Oscillation),AO and North Pacific could be linked through the planetary wave propagation, which acts as the atmospheric bridge. The zonal symmetric and asymmetric structures both have association with these Rossby wave activities.     

模拟电路的故障回路和故障网孔的诊断

文中给出了模拟电路多故障诊断的回路法和网孔法,使K故障诊断理论内容完整,在某些情况下,回路诊断法具有一定的优越性。     

SIMULATION STUDY OF IMAGING OF UNDERWATER BOTTOM TOPOGRAPHY BY SYNTHETIC APERTURE RADAR

1 .　ＩＮＴＲＯＤＵＣＴＩＯＮＳｙｎｔｈｅｔｉｃＡｐｅｒｔｕｒｅＲａｄａｒ (ＳＡＲ)ｉｓａｎｅｗｒｅ ｍｏｔｅｓｅｎｓｉｎｇｄｅｔｅｃｔｉｏｎａｐｐｒｏａｃｈｔｏｅｎｖｉｒｏｎｍｅｎｔａｎｄｒｅｓｏｕｒｃｅ .Ｉｔｐｏｓｓｅｓｓｅｓｇｏｏｄｒａｎｇｅａｎｄａｚｉｍｕｔｈｒｅｓｏ ｌｕｔｉｏｎ ,ｔｈｕｓｐｒｏｕｃｉｎｇｉｍａｇｅｓｓｉｍｉｌａｒｔｏｖｉｓｉｂｌｅｌｉｇｈｔｐｈｏｔｏｓ.Ｃｏｍｐａｒｅｄｗｉｔｈｓｕｃｈｒｅｍｏｔｅｓｅｎｓｉｎｇｉｍａｇｉｎｇｔｅｃｈｎｉｑｕｅａｓｏｐｔｉｃｓ ,ｉｎｆｒａｒ…     

Luminescence and bandgap studies of high purity MgXZn1−XTe Ternary Alloys

High purity Mg_XZn_1−XTe alloys in the range of 0 < x < 0.45 have been prepared by the Bridgman technique. Wavelength modulated reflectivity measurements have been performed at 300 K. The structure of the spectra near the fundamen-tal edge is similar to the one for ZnTe. The bandgap va-riation versus the composition x is Eg (x) = 2.271 + 0.7 x + 0.6 x². Cathodoluminescence at 300K and 110K shows a single bandedge narrow peak. The variation with composition of the emission peak energy Ep (X) follows the same law as Eg (x). Undoped crystals are highly resistive (> 10⁵Ωcm) but when phosporus is introduced into the melt, the resis-tivity decreases to 10³ Ωcm.     

SOME FEATURES OF RING 94S-A KUROSHIO DETACHED EDDY IN THE SOUTH CHINA SEA

1 .　ＩＮＴＲＯＤＵＣＴＩＯＮＩｎＳｅｐｔｅｍｂｅｒ 1 994,ａｗａｒｍ ｃｏｒｅｒｉｎｇｗａｓｄｉｓ ｃｏｖｅｒｅｄｎｅａｒｔｈｅｃｏｎｔｉｎｅｎｔａｌｓｌｏｐｅｏｆｔｈｅｎｏｒｔｈｅｒｎＳｏｕｔｈＣｈｉｎａＳｅａ (ＳＣＳ ,ｈｅａｒａｆｔｅｒ) ,ａｎｄｗａｓｄｉｓ ｃｕｓｓｅｄｉｎｄｅｔａｉｌｆｏｒｔｈｅｆｉｒｓｔｔｉｍｅ (Ｌｉｅｔａｌ.,1 997;Ｌｉｅｔａｌ.,1 998) .Ｔｈｉｓｒｉｎｇ (Ｒｉｎｇ 94Ｓ ,ｎａｍｅｄａｆｔｅｒｔｈｅｏｂｓｅｒｖｅｄｙｅａｒａｎｄｍｏｎｔｈ)ｉｓａｎｗａｒｍｃｏｒｅａｎｔｉ ｃｙ…