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1.
日前,欧盟发布G/TBT/N/EU/75通报,通报了计算机和计算机服务器的ErP指令实施条例草案,规定了计算机和计算机服务器产品的最低能源效率和信息要求,拟批准日期是2013年5月。该实施条例是ErP框架指令(2009/125/EC)下关于计算机产品的具体生态设计要求,该条例要求一旦正式生效,不符合要求的产品将不允许在欧盟市场销售。 相似文献
2.
Heterophase equilibria in the Ga x In1 − x Bi y As z Sb1 − y − z -InSb and InBi y As z Sb1 − y − z -InSb systems have been analyzed within the simple solution approximation. Ga x In1 − x Bi y As z Sb1 − y − z /InSb and InBi y As z Sb1 − y − z /InSb heterostructures have been grown in a temperature gradient, and their composition and structural perfection have been assessed. 相似文献
3.
Örjan Sävborg 《Materials Research Bulletin》1976,11(3):275-279
Phase analysis studies on the systems () performed by means of X-ray powder photographs of samples prepared 1000K – 1225K have established the existence of the following phases:Metal-metal distances in the orthorhombic rhenium dioxide phases, derived from powder photographs, show slight changes with the value. 相似文献
4.
S. L. Young T. C. Wu L. Horng C. H. Lin H. Z. Chen M. C. Kao C. R. Ou N. F. Shih J. B. Shi 《Journal of Superconductivity and Novel Magnetism》2010,23(6):953-956
The ceramic composites, (La0.7Pb0.3MnO3)1−x
(SiO2)
x
, with diluted magnetic properties are prepared using solid-sate sintering route. Magnetization processes of (La0.7Pb0.3MnO3)1−x
(SiO2)
x
composites are explored in this study. Ferromagnetism is gradually attenuated due to the magnetic dilution induced by the
increase of SiO2 content. Clearly, irreversible behavior is observed in the zero-field cooling and the field cooling (ZFC–FC) curves at a
low field of 100 Oe. Saturation magnetization decreases as x increases while ferromagnetic transition temperature remains around 346 K for all composites. All the composites exhibit
ferromagnetic hysteresis behavior which can be modeled by the law of the approach to saturation in the form M=M
S(1−a/H). The term a/H expresses the deviation of magnetization from saturation. The smaller factor a for La0.7Pb0.3MnO3-rich samples results in sharper square curve which should be associated with the long-range spin order of ferromagnetic coupling. 相似文献
5.
未来移动通信的发展或是演进应该是多种无线接入技术的共存,相互补充、相互融合,协同服务。2010年7月初,中国移动明确了对GSM/TD-SCDMA/WLAN/TD-LTE四网建设的发展策略。本文简要介绍一下四网的现状、定位、发展策略及业务融合等问题。 相似文献
6.
2012年底,印度电子与信息技术部向WTO通报了关于《电子与信息技术商品(强制注册要求)法令2012》的G/TBT/N/IND/44号通报。此次印度通报主要是针对音视频产品、信息技术设备、微波炉、电子时钟等15种电子电器产品提出了强制性注册要求,通报法规一旦实施,将对我国相关电子电器产品出口印度产生较大影响。 相似文献
《高分子材料科学与工程》2021,37(12)
8.
以Li0.5La0.5TiO3为包覆物,制备了固体电解质包覆的LiNil/3Co1/3Mnl/3O2正极材料。采用XRD、SEM对材料进行了表征:XRD显示未包覆的材料具有α-NaFeO2层状结构,粒径在200~300nm之间,包覆后材料粒径略有增大,包覆层具有ABO3型固体电解质结构。包覆层的致密程度及材料的循环稳定性与热处理温度有关。包覆后400℃热处理得到的材料首次放电比容量为185mAh/g,较未包覆材料容量有所提高,50次循环后其容量仍能达到156.5mAh/g,表明包覆物Li0.5La0.5TiO3对LiNil/3Co1/3Mnl/3O2具有保护作用。 相似文献
9.
通过熔融共混制备聚丙烯(PP)/马来酸酐接枝聚丙烯(PP-g-MAH)/滑石粉(Talc)/环氧树脂(EP)复合材料,研究了E-51/504/554(55.6/42.4/2,E1)、E-51/EDA/554(92.2/7.8/0.01,E2)、E-20/2E4MZ(100/4,E3)三种EP体系及其含量对复合材料力学性能的影响,结果表明,E-1对复合材料的弯曲模量改善最显著,当加入4%的E1时,复合材料的弯曲模量达到最大值,提高了29.1%。傅里叶红外光谱(FT-IR)分析表明,EP与PP-g-MAH发生了酯化反应。观察复合材料的微观结构,发现EP阻止Talc的凝聚,加强了两相界面作用力。 相似文献
10.
在Al2O3颗粒补强锆英石陶瓷的研究基础上,探讨了Al2O3与ZrO2共同对锆英石陶瓷的协同补强增韧行为.制备的锆英石基复合材料的室温抗弯强度和断裂韧性分别可达383.31MPa、4.39 MPa·m12.采用XRD分析了复合材料的相组成,采用SEM观察复合材料的断面形貌.结果显示:ZrSiO4为主要晶相,另外还有少量Al2O3和ZrO2存在;第二种增强体ZrO2的最佳引入量为20%(质量分数);确定复合材料的强韧化是由Al2O3和ZrO2颗粒引起的裂纹偏转、微裂纹增韧与ZrO2颗粒引起的相变增韧共同作用而实现的,断裂方式主要为穿晶断裂. 相似文献
11.
釆用固态反应法合成超导体Bi2Sr2CaCu2Ox(Bi2212),使用摩擦实验机从液氮温度至室温对其摩擦学特性进行研究。研究表明:室温Bi2212与不锈钢盘对摩时摩擦系数约为0.35,当温度降至超导转变温度以下(液氮温度),摩擦系数大幅度降低至0.11,非常稳定。为改善Bi2212常温摩擦性能,添加Ag制备出Ag/Bi2212超导复合材料,XRD、SEM和EDS分析表明,Ag未进入Bi2212晶格,保证了Bi2212的超导电性,Ag的添加提高了复合材料密度和韧性,在正常载荷和滑行速度下Ag质量分数为10 %时摩擦系数为0.2,15%Ag/Bi2212磨损率最低,为9. 5×10-5 mm3 (N·m)-1。分布基体中的Ag能有效抑制裂纹萌生和扩展并在摩擦作用下向表面转移,在摩擦表面形成一层Ag转移膜,其低剪切强度起到很好的润滑作用,同时将摩擦产生的热量及时传导出去,使复合材料表现出良好的减摩耐磨性能。 相似文献
12.
13.
S. J. Hao W. T. Jin X. J. Zhang Y. Zhao H. Zhang 《Journal of Superconductivity and Novel Magnetism》2010,23(5):819-822
The co-doped compounds of Y1−x
Ca
x
Ba2Cu3−x
Al
x
O
z
, with x from 0.1 to 0.4, were synthesized through a solid-state reaction method. Structural and superconducting properties have been
investigated by X-ray diffraction, Rietveld refinement, and DC magnetization measurement. The lattice constant a decreases while b increases with the addition of x. The difference between a and b diminishes gradually. Careful study of the crystalline structure shows that the critical temperature (T
c
) changes monotonically with some local structural parameters, such as the difference between Ba and Cu(2) atoms’ Z coordinates,
the bond length of Cu(2)–O(4), and the bond angle of Cu(2)–O(2)–Cu(2), which are all closely related to the interaction between
the perovskite block and the rock salt block in the unit cell. The results indicated that the influence of the crystalline
structure on superconductivity is important and independent of the carrier concentration. 相似文献
14.
The solubility of Nd at the Ba sites and the superconductivity of YBa2–x
Nd
x
Cu3O
y
were investigated by X-ray powder diffraction and measurements of the electrical resistance and ac susceptibility. The single Re123 phase was obtained for x0.30. The onset transition temperature
is insensitive to the Nd content x in the region of x0.40. All are higher than 95 K. The zero resistance transition temperatures
, however, exhibits two-step variation with the increase of x. For x0.25,
are all above 92 K. The highest
of 94 K was obtained for x=0.25. For x0.3
drops sharply to about 84 K. Finally
falls to 30 K and
is below 10 K for x=0.5. The two-step variation of T
c might be an indication of the existence of two trap levels for holes. 相似文献
15.