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101.
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Herein, we report an efficient process for preparing monodisperse Au@SiO2 nanoparticles using homogeneous shaking and without the use of surface‐coupling silane agents or large stabilizers. The resulting pure‐silica surface of the Au@SiO2 nanoparticles is very important for straightforward surface functionalization with different functional groups via well‐established silica surface chemistry. Subsequent covalent bioconjugation of the aldehyde‐functionalized Au@SiO2 nanoparticles with various biomolecules is successfully employed to make robust nanoprobes for fast, colorimetric DNA and protein detection based on the sequence‐specific hybridization properties of DNA and the specific binding affinity between proteins, respectively.  相似文献   
103.
The Testbed for Distributed Processing, or Ted, consists of Intel Corp.'s iSBC 8086 single board computers (SBCs) organized into groups or clusters. Each cluster consists of several SBCs that communicate via a shared memory. Intercluster communication occurs through an Ethernet interface. A hardware monitor designed and implemented to handle the monitoring activities within a cluster in the Ted system is described. By using specified patterns and don't-care masks, the system can detect accesses to selected data, addresses, or blocks of addresses. This function helps monitor events such as the access or usage of a memory location or a group of mailbox addresses. It also determines the amount of time consumed by the performance of specific operations  相似文献   
104.
本文介绍北京核电站模拟器硬件构成并分析其功能和特点。  相似文献   
105.
A pilot-scale fluidised pellet bed (FPB) bioreactor, which combines chemical coagulation, biological degradation, particle pelletisation and separation in one unit, was applied for onsite wastewater treatment and reuse. As a result of rational use of inorganic coagulant and organic polymer and moderate mechanical agitation, spherical particles were generated in the upflow column and a well-fluidised bed was formed. With a continuous supply of dissolved oxygen through a recycling loop, an aerobic condition was kept in the bottom section of the FPB column. Under such conditions the pellets in the FPB column showed the following characteristics: (1) compact structure and high density; (2) rich in microorganisms; and (3) high MLSS and MLVSS concentrations. Therefore, the FPB bioreactor achieved more than 90% removal of SS, COD, BOD and TP from raw domestic wastewater within a total hydraulic retention time (HRT) of only about 30 minutes. It also showed nitrification and denitrification ability and the TN removal could be about 50% as the recycling ratio was increased to 1:1. The treated water quality is generally competitive with the secondary effluent from a conventional activated sludge process. With these advantages the FPB bioreactor is recommendable as a compact system for onsite wastewater treatment and reuse.  相似文献   
106.
文章结合平常工作经验,对低水头电站规划设计中需要注意的包括坝(闸)址选择,库区淹(浸)没、枢纽布置、施工导流、正常蓄水位与上下游梯级衔接五个问题加以分析探讨,进行总结和思考。  相似文献   
107.
A technology for increasing both the two-terminal gate-drain breakdown and subsequently the three-terminal-off-state breakdown of AlInAs/GaInAs high-electron-mobility transistors (HEMTs) to record values without substantial impact on other parameters is presented. The breakdown in these structures is dependent on the multiplication of electrons injected from the source (channel current) and the gate (gate leakage) into the channel. In addition, holes are generated by high fields at the drain and are injected back into the gate and source electrodes. These phenomena can be suppressed by increasing the gate barrier height and alleviating the fields at the drain. Both have been achieved by incorporating a p+-2DEG junction as the gate that modulates the 2DEG gas and by utilizing selective regrowth of the source and drain regions by MOCVD. The 1-μm-gate-length devices fabricated have two-terminal gate-drain and three-terminal-off-state breakdown voltages of 31 V and 28 V, respectively  相似文献   
108.
PC/ABS合金的研制及其在汽车上的应用   总被引:6,自引:0,他引:6  
对PC/ABS合金开发和研制及其在汽车上的应用作了评述。介绍了上海杰事公司在该领域的进展。  相似文献   
109.
110.
刘培锷 《冶金设备》1995,(6):11-15,18
对1600圆盘式高速金属冷锯机进行了锯切功率的实验研究。对某厂四种有代表性的产品,用不同的进锯速度,实测每种条件下的锯切功率变化,和最大瞬时锯切功率与平均锯切功率之比。并以实测数据为基础,得出每种产品以进锯速度为自变量的平均锯切功率回归公式。这些工作,不仅可以为这种冷锯机锯切功率的理论研究提供依据,还可直接为使用和设计这种冷锯机给出具体参考数据。  相似文献   
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