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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   

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The GaAs-based double-heterojunction P-i-N structures using InzGa1–zAs1–xyNxSby as the i-layer is investigated for the first time using solid source molecular beam epitaxy. High quality coherent bulk InGaAsN3.45%Sb (0.5 m) with a lattice-mismatch of 2.6 × 10–3 can be achieved due to the surfactant properties of antimony, while the bulk InGaAsN2% at 0.5 m with 1.06× 10–3 mismatch is fully relaxed. Rapid thermal annealing (RTA) resulted in 25 meV low temperature (LT) photoluminescence (PL) full-width half-maximums (FWHM) for the bulk InGaAsNSb layers. InGaAsNSb experiences 30% less blueshifting with subjected under the same annealing conditions as InGaAsN with similar N content. Room temperature (RT) absorption measurements are in the range of 0.9–1.4 eV. The absorption edge of 1.41 m is achieved for sample D4.  相似文献   

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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   

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Thorium-doped YBa2(1 – x)Sr x Th x Cu3O7 – high-T c ceramic superconductors (with x = 0.1, 0.15, 0.2, and 0.3) have been carefully prepared by the usual ceramic procedure and sintering technique, with intermediate grindings and annealing under a stream of compressed-air atmosphere. The structural parameters of the prepared samples are calculated and interpreted using X-ray diffraction analysis. The electrical properties are also carefully investigated in the present work using the four-probe technique. Results obtained were compared, explained, interpreted, and discussed in detail; meanwhile, the major goal of the present work and promising deductions are attained at.  相似文献   

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By means of a solid-phase synthesis two types of microwave dielectric materials are obtained as follows: Ba1–xSrx(Zn1/3Ta2/3)0.94Ti0.06O3, where x = 0.20, 0.25, 0.30, 0.35 and 0.40 at sintering temperature TS = 1350, 1400 and 1450 C; Ba(Zn1/3Nb2/3)1–xZrxO3, where x = 0.04, 0.06, 0.08 and 0.10 at TS = 1300, 1350, and 1400 C. The microwave characteristics of the materials are investigated at f = 10 GHz. The composition Ba(Zn1/3Nb2/3)1–xZrxO3 demonstrates r = 38, Q = 6100 and f = +15 ppm C–1 and the composition Ba0.80Sr0.20- (Zn1/3Ta2/3)0.94Ti0.06O3 has r = 42, Q = 8200 and f = –13 ppm C–1. The composition Ba0.75Sr0.25(Zn1/3Ta2/3)0.94Ti0.06O3 has r = 40, Q = 6500 and low f = –13 C–1 ppm. This composition could be used successfully for realisation of dielectric microwave resonators for the satellite television.  相似文献   

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The transport properties of p-type Pb1–x Eu x Te epitaxial layers were studied as a function of Eu content, temperature, and magnetic field. The low-temperature hole mobility is drastically reduced when the Eu concentration is increased from 0 to 6%, while the hole concentration remains almost constant. A metal-insulator transition was observed for x 0.04, which is probably induced by the disorder caused by the introduction of Eu. For temperatures down to 10 K, only positive magnetoresistance has been observed at low magnetic fields. An anomalous behavior of the resistivity as a function of temperature has been detected for a Eu content about 5%, which is attributed to the resonance between the localized Eu 4f level and the valence band maximum.  相似文献   

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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   

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