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991.
介绍了高速12位D/A转换器的电路设计,采用2μm等平面高速双极工艺,研制出数据更新率≥80MHz,线性误差≤3LSB,微分非线性≤3LSB的12位D/A转换器电路.  相似文献   
992.
993.
应用于HDI的激光钻孔半固化片的方法和其它常规材料相比具有的优缺点。  相似文献   
994.
介绍了高阻厚层反型外延片的一种实用生产技术,即在PE-2061S外延设备上,采取特殊的工艺控制在电阻率小于0.02Ω·cm的p型低阻衬底上实现了高阻厚层n型外延生长,外延层电阻率大于40Ω·cm,厚度大于100μm. 研究表明:该外延材料完全可以满足IGBT器件制作的需要.  相似文献   
995.
基于BiCMOS技术,进行了高速数字/模拟转换器研究. 以并行输入类型,电流工作模式的16位D/A转换器为载体,进行了电路设计、工艺制作和测试. 在±5.0V工作电压下,测试得到转换速率≥30MSPS,建立时间为50ns,增益误差为±8% FSR,积分非线性误差为1/2 LSB,功耗为500mW.  相似文献   
996.
The {100} facet of single-crystalline TiO2(B) is an ideal platform for inserting Li ions, but it is hard to be obtained due to its high surface energy. Here, the single-crystalline TiO2(B) nanobelts from H2Ti3O7 with nearly 70% {100} facets exposed are synthesized, which significantly enhances Li-storage capacity. The first-principle calculations demonstrate an ab in-plane 2D diffusion through the exposed {100} facets. As a consequence, the nanobelts can significantly accommodate Li ions in LiTiO2 formula with specific capacity up to 335 mAh g−1, which is in good agreement with the electrochemical characterizations. Coating with conductive and protective poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate), the cut-off discharge voltage is as low as 0.5 V, leading to a capacity of 160.7 mAh g−1 after 1500 cycles with a retention rate of 66% at 1C. This work provides a practical strategy to increase the Li-ion capacity and cycle stability by tailoring the crystal orientation and nanostructures.  相似文献   
997.
Garnet-type oxide Li6.4La3Zr1.4Ta0.6O12 (LLZTO) has attracted considerable attention as a highly promising solid state electrolyte. However, its high ionic conductivity is achievable only after high temperature sintering (≈1200 °C) to form dense pellets but with detrimental brittleness and poor contact with electrodes. Herein, a novel strategy to achieve high Li+ ion conductivity of LLZTO without sintering is demonstrated. This is realized by ball milling LLZTO together with LiBH4, which results in a LLZTO composite with unique amorphous dual coating: LiBO2 as the inner layer and LiBH4 as the outer layer. After cold pressing the LLZTO composite powders under 300 MPa to form electrolyte pellets, a high Li+ ion conductivity of 8.02 × 10–5 S cm–1 is obtained at 30 °C, which is four orders of magnitude higher than that of the non-sintered pristine LLZTO pellets (4.17 × 10–9 S cm–1). The composite electrolyte displays an ultrahigh Li+ transference number of 0.9999 and enables symmetric Li–Li cells to be cycled for 1000 h at 60 °C and 300 h at 30 °C. The significant improvements are attributed to the continuous ionic conductive network among LLZTO particles facilitated by LiBH4 that is chemically compatible and electrochemically stable with Li metal electrode.  相似文献   
998.
Stretchable self-healing supercapacitors (SCs) can operate under extreme deformation and restore their initial properties after damage with considerably improved durability and reliability, expanding their opportunities in numerous applications, including smart wearable electronics, bioinspired devices, human–machine interactions, etc. It is challenging, however, to achieve mechanical stretchability and self-healability in energy storage technologies, wherein the key issue lies in the exploitation of ideal electrode and electrolyte materials with exceptional mechanical stretchability and self-healing ability besides conductivity. Conductive hydrogels (CHs) possess unique hierarchical porous structure, high electrical/ionic conductivity, broadly tunable physical and chemical properties through molecular design and structure regulation, holding tremendous promise for stretchable self-healing SCs. Hence, this review is innovatively constructed with a focus on stretchable and self-healing CH based electrodes and electrolytes for SCs. First, the common synthetic approaches of CHs are introduced; then the stretching and self-healing strategies involved in CHs are systematically elaborated; followed by an explanation of the conductive mechanism of CHs; then focusing on CH-based electrodes and electrolytes for stretchable self-healing SCs; subsequently, application of stretchable and self-healing SCs in wearable electronics are discussed; finally, a conclusion is drawn along with views on the challenges and future research directions regarding the field of CHs for SCs.  相似文献   
999.
Mild-temperature photothermal therapy (PTT) of tumors has been intensively explored and adopted in preclinical/clinical trials in recent years. Nevertheless, tumor thermoresistance significantly compromises the therapeutic efficacy of mild-temperature PTT, and therefore, the extra addition of anti-thermoresistance agent is needed. Herein, by rational design of a peptide-hydroxychloroquine (HCQ) conjugate Cypate-Phe-Phe-Lys(SA-HCQ)-Tyr(H2PO3)-OH (Cyp-HCQ-Yp), a “smart” strategy of enzyme-triggered simultaneously intracellular photothermal nanoparticle formation and HCQ release is proposed for autophagy-inhibited mild-temperature PTT of tumor. In vitro results show that, under sequential catalysis of enzymes alkaline phosphatase and carboxylesterase, Cyp-HCQ-Yp is converted to Cypate-Phe-Phe-Lys(SA)-Tyr-OH (Cyp-Y) which self-assembles into its nanoparticle Cyp-NP and HCQ is released from Cyp-HCQ-Yp. By comparing with two control agents, it is validated that the exceptional therapeutic effect of Cyp-HCQ-Yp on tumor in vivo is achieved by its dual-enzyme-controlled intracellular nanoparticle formation and autophagy inhibition in tumors.  相似文献   
1000.
Mercury, lead, and cadmium are among the most toxic and carcinogenic heavy metal ions (HMIs), posing serious threats to the sustainability of aquatic ecosystems and public health. There is an urgent need to remove these ions from water by a cheap but green process. Traditional methods have insufficient removal efficiency and reusability. Structurally robust, large surface-area adsorbents functionalized with high-selectivity affinity to HMIs are attractive filter materials. Here, an adsorbent prepared by vulcanization of polyacrylonitrile (PAN), a nitrogen-rich polymer, is reported, giving rise to PAN-S nanoparticles with cyclic π-conjugated backbone and electronic conductivity. PAN-S can be coated on ultra-robust melamine (ML) foam by simple dipping and drying. In agreement with hard/soft acid/base theory, N- and S-containing soft Lewis bases have strong binding to Hg2+, Pb2+, Cu2+, and Cd2+, with extraordinary capture efficiency and performance stability. Furthermore, the used filters, when collected and electrochemically biased in a recycling bath, can release the HMIs into the bath and electrodeposit on the counter-electrode as metallic Hg0, Pb0, Cu0, and Cd0, and the PAN-S@ML filter can then be reused at least 6 times as new. The electronically conductive PAN-S@ML filter can be fabricated cheaply and holds promise for scale-up applications.  相似文献   
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