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11.
虽然应用材料公司(Applied Materials)并不以光刻而闻名,但它还是想提醒大家:光刻不是只有印制(printing)。正如应用材料公司的薄膜事业群总经理Farhad Moghadam在SPIE的先进光刻会议的新闻发布午宴  相似文献   
12.
In this paper, the outage probability (OP) performance of multiple-relay-based incremental amplify-and-forward relaying device-to-device networks with transmit antenna selection (TAS) over N-Nakagami fading channels is investigated. The exact closed-form expressions for OP of the optimal and suboptimal TAS schemes are derived. The power allocation problem is formulated for performance optimization. Then the OP performance under different conditions is evaluated through numerical simulations to verify the analysis. The simulation results showed that optimal TAS scheme has a better OP performance than suboptimal TAS scheme, but the performance gap between the optimal and suboptimal schemes diminishes by increasing the number of antennas at the source; the fading coefficient, the number of cascaded components, the relative geometrical gain, the number of antennas, and the power-allocation parameter have an important influence on the OP performance.  相似文献   
13.
The distribution of water diffusion in biological tissues may be estimated by a 3-D Fourier transform (FT) of diffusion-weighted measurements in q-space. In this study, methods for estimating diffusion spectrum measures (the zero-displacement probability, the mean-squared displacement, and the orientation distribution function) directly from the q-space signals are described. These methods were evaluated using both computer simulations and hybrid diffusion imaging (HYDI) measurements on a human brain. The HYDI method obtains diffusion-weighted measurements on concentric spheres in q-space. Monte Carlo computer simulations were performed to investigate effects of noise, q-space truncation, and sampling interval on the measures. This new direct computation approach reduces HYDI data processing time and image artifacts arising from 3-D FT and regridding interpolation. In addition, it is less sensitive to the noise and q-space truncation effects than conventional approach. Although this study focused on data using the HYDI scheme, this computation approach may be applied to other diffusion sampling schemes including Cartesian diffusion spectrum imaging.  相似文献   
14.
Comprehensive analyses of the atomic structure using advanced analytical transmission electron microscopy-based methods combined with atom probe tomography confirm the presence of distinct glass–glass interfaces in a columnar Cu-Zr nanoglass synthesized by magnetron sputtering. These analyses provide first-time in-depth characterization of sputtered film nanoglasses and indicate that glass–glass interfaces indeed present an amorphous phase with reduced mass density as compared to the neighboring amorphous regions. Moreover, dedicated analyses of the diffusion kinetics by time-of-flight secondary ion mass spectroscopy (ToF SIMS) prove significantly enhanced diffusivity, suggesting fast transport along the low density glass–glass interfaces. The present results further indicate that sputter deposition is a feasible technique for reliable production of nanoglasses and that some of the concepts proposed for this new class of glassy materials are applicable.  相似文献   
15.
Photodynamic therapy (PDT) has emerged as an attractive alternative in cancer therapy, but its therapeutic effects are limited by the nonselective subcellular localization and poor intratumoral retention of small-molecule photosensitizes. Here a fiber-forming nanophotosensitizer (PQC NF) that is composed of mitochondria targeting small molecules of amphiphilicity is reported. Harnessing the specific mitochondria targeting, the light-activated PQC NFs produce approximately 110-fold higher amount of reactive oxygen species in cells than free photosensitizers and can dramatically induce mitochondrial disruption to trigger intense apoptosis, showing 20–50 times better in vitro anticancer potency than traditional photosensitizers. As fiber-shaped nanomaterials, PQC NFs also demonstrated a long-term retention in tumor sites, solving the challenge of rapid clearance of small-molecule photosensitizers from tumors. With these advantages, PQC NFs achieve a 100% complete cure rate in both subcutaneous and orthotopic oral cancer models with the administration of only a single dose. This type of single small molecule-assembled mitochondria targeting nanofibers offers an advantageous strategy to improve the in vivo therapeutic effects of conventional PDT.  相似文献   
16.
The authors present the characterization of the first dynamic RAM (DRAM) fabricated in a technology specifically optimized for cryogenic operation. With the power supply adjusted to assure hot-electron reliability, the 25-ns 4-Mb low-temperature (LT) chips operated 3 times faster than conventional chips. The LT-optimized chips functioned properly with cycle times as fast as 45 ns, and with a toggle-mode data rate of 667 Mb/s. Wide operating margins and a very large process window for data retention were demonstrated. At a temperature of 85 K the storage retention time of the trench-capacitor memory cells exceeded 8 h. This study shows that the performance leverage offered by low temperature applies equally well to DRAM and to logic. There is no limitation inherent to memory  相似文献   
17.
经济危机不断深入,并且与产业周期的低谷共同作用,半导体产业的生存压力日渐增大。越来越多的器件制造商和代工厂开始在光伏领域寻找机会以期度过财政难关。市场分析公司IC Insights(亚利桑那州,Scottsdale)主要集中在半导体领域,目前也开始向PV产业转移,开始为半导体产业的企业进入这个新兴市场提供帮助。  相似文献   
18.
A β‐FeSi2–SiGe nanocomposite is synthesized via a react/transform spark plasma sintering technique, in which eutectoid phase transformation, Ge alloying, selective doping, and sintering are completed in a single process, resulting in a greatly reduced process time and thermal budget. Hierarchical structuring of the SiGe secondary phase to achieve coexistence of a percolated network with isolated nanoscale inclusions effectively decouples the thermal and electrical transport. Combined with selective doping that reduces conduction band offsets, the percolation strategy produces overall electron mobilities 30 times higher than those of similar materials produced using typical powder‐processing routes. As a result, a maximum thermoelectric figure of merit ZT of ≈0.7 at 700 °C is achieved in the β‐FeSi2–SiGe nanocomposite.  相似文献   
19.
This report demonstrates a wearable elastomer‐based electronic skin including resistive sensors for monitoring finger articulation and capacitive tactile pressure sensors that register distributed pressure along the entire length of the finger. Pressure sensitivity in the order of 0.001 to 0.01 kPa?1 for pressures from 5 to 405 kPa, which includes much of the range of human physiological sensing, is achieved by implementing soft, compressible silicone foam as the dielectric and stretchable thin‐metal films. Integrating these sensors in a textile glove allows the decoupling of the strain and pressure cross‐sensitivity of the tactile sensors, enabling precise grasp analysis. The sensorized glove is implemented in a human‐in‐the‐loop system for controlling the grasp of objects, a critical step toward hand prosthesis with integrated sensing capabilities.  相似文献   
20.
Noncentrosymmetric (NCS) tetrel pnictides have recently generated interest as nonlinear optical (NLO) materials due to their second harmonic generation (SHG) activity and large laser damage threshold (LDT). Herein nonmetal-rich silicon phosphides RuSi4P4 and IrSi3P3 are synthesized and characterized. Their crystal structures are reinvestigated using single crystal X-ray diffraction and 29Si and 31P magic angle spinning NMR. In agreement with previous report RuSi4P4 crystallizes in NCS space group P1, while IrSi3P3 is found to crystallize in NCS space group Cm, in contrast with the previously reported space group C2. A combination of DFT calculations and diffuse reflectance measurements reveals RuSi4P4 and IrSi3P3 to be wide bandgap (Eg) semiconductors, Eg = 1.9 and 1.8 eV, respectively. RuSi4P4 and IrSi3P3 outperform the current state-of-the-art infrared SHG material, AgGaS2, both in SHG activity and laser inducer damage threshold. Due to the combination of high thermal stabilities (up to 1373 K), wide bandgaps (≈2 eV), NCS crystal structures, strong SHG responses, and large LDT values, RuSi4P4 and IrSi3P3 are promising candidates for longer wavelength NLO materials.  相似文献   
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