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51.
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The stability of liquid jet of dichloromethane in dense carbon dioxide was investigated in an aerosol solvent extraction system (ASES). The stability experiments were carried out at pressures ranging 30–150 bar and a temperature of 308 K, with a nozzle size diameter of 0.254 mm. Interfacial tensions of dichloromethane–carbon dioxide system were measured using a capillary rise method to correlate the stability of liquid jets with a dimensionless number. A new dimensionless number, Z*, was proposed to define an atomization flow regime of the liquid jets in dense carbon dioxide.  相似文献   
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4 Gb/s/pin 32 bit 512 Mb GDDR4 (Graphics Double Data Rate 4) SDRAM was implemented by using an 80 nm CMOS process. It employs a data bus inversion (DBI) coding to overcome the bottleneck of a parallel single-ended signaling, a power consumption of I/O, power supply noise, and crosstalk. Both DBI AC and DC modes are combined to a single circuit by eliminating the feedback path of a conventional DBI AC circuit while achieving high-speed operation. The proposed DBI circuit uses an analog majority voter insensitive to mismatch for small area and delay. Ronmiddot tuning further improves the voltage and time margin by adding a user-supplied offset to auto-calibrated Ronmiddot. In addition, a dual duty cycle corrector (DCC) is used to reduce duty error and jitter by averaging two outputs of two DCCs. Measured results show that DBI DC coding reduces the peak-to-peak jitter from 65.5 ps to 44.5 ps and the voltage fluctuation from 183 mV to 115 mV at the data rate of 4 Gb/s with the 2 V.  相似文献   
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In this paper, we have experimentally investigated the impact of lateral and vertical scaling of In0.7Ga0.3As high-electron-mobility transistors (HEMTs) onto their logic performance. We have found that reducing the In0.52Al0.48As insulator thickness results in much better electrostatic integrity and improved short-channel behavior down to a gate length of around 60 nm. Our nearly enhancement-mode 60-nm HEMTs feature VT = -0.02 V, DIBL = 93 mV/V, S = 88 mV/V, and ION/IOFF = 1.6 times104, at V DD = 0.5 V. We also estimate a gate delay of CV/I = 1.6 ps at VDD = 0.5 V. We have benchmarked these devices against state-of-the-art Si CMOS. For the same leakage current, which includes the gate leakage current, the InGaAs HEMTs exhibit 1.2times more current drive (ION) than the state-of-the-art 65-nm low-power CMOS technology at V DD = 0.5 V.  相似文献   
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Effects of a Cu-based catalyst on the catalytic performance in alcohol-hydrocarbon synthesis from syngas have been investigated, using various supports. Under the different porosities of three supports (zinc oxide, activation carbon, and titanium dioxide), whereas Cu/ZnO produces one liquid phase of major mixed alcohols, Cu/AC and Cu/TiO2 create two phases, alcohol (~75%) and hydrocarbon (~25%). X-ray diffraction shows that CuO impregnated on supports undergoes a complete reduction of metallic copper Cu0, which is the real active phase in the catalytic process. The Cu/TiO2 catalyst showed the highest ethanol composition in a mixed alcohol phase under GHSV 18,000 h?1, 30 bar, and 300 °C.  相似文献   
58.
A functional dental adhesive resin system with antimicrobial properties was developed using human serum albumin (HSA) nanoparticles as the drug delivery carrier. HSA nanoparticles loaded with chlorhexidine (CHX) diacetate, a model antimicrobial drug, were prepared using a desolvation technique. The resulting CHX-loaded HSA nanoparticles were incorporated into a commercial methyl methacrylate (MMA)-based resin. The size of the nanoparticles ranged 50–300 nm, and the nanoparticles were dispersed homogeneously in the resin matrix. The CHX-loaded HSA nanoparticles showed an early release burst of ~20 % of the total CHX by day 5, followed by the sustained release of the remaining CHX over the next 20 days. In contrast, the resin matrix containing the HSA nanoparticles showed a sustained release of CHX without an early release burst in a 4-week immersion study. In the agar diffusion test, the resin matrix incorporating the CHX-loaded HAS nanoparticles showed a larger growth inhibition zone against Streptococcus mutans than the resin matrix alone, indicating that this delivery platform potently imparts antibacterial activity to the resins. These results also suggest that CHX, which inhibits the growth of oral bacteria, can be incorporated efficiently into the MMA-based resin matrix using HSA nanoparticles.  相似文献   
59.
Atopic dermatitis (AD) is a refractory and relapsing skin disease with a complex and multifactorial etiology. Various congenital malformations and environmental factors are thought to be involved in the onset of the disease. The etiology of the disease has been investigated, with respect to clinical skin symptoms and systemic immune response factors. A gut microbiome–mediated connection between emotional disorders such as depression and anxiety, and dermatologic conditions such as acne, based on the comorbidities of these two seemingly unrelated disorders, has long been hypothesized. Many aspects of this gut–brain–skin integration theory have recently been revalidated to identify treatment options for AD with the recent advances in metagenomic analysis involving powerful sequencing techniques and bioinformatics that overcome the need for isolation and cultivation of individual microbial strains from the skin or gut. Comparative analysis of microbial clusters across the gut–skin axis can provide new information regarding AD research. Herein, we provide a historical perspective on the modern investigation and clinical implications of gut–skin connections in AD in terms of the integration between the two microbial clusters.  相似文献   
60.
InP quantum dots (QDs) based light‐emitting diodes (QLEDs) are considered as one of the most promising candidates as a substitute for the environmentally toxic Cd‐based QLEDs for future displays. However, the device architecture of InP QLEDs is almost the same as the Cd‐based QLEDs even though the properties of Cd‐based and InP‐based QDs are quite different in their energy levels and shapes. Thus, it is highly required to develop a proper device structure for InP‐based QLEDs to improve the efficiency and stability. In this work, efficient, bright, and stable InP/ZnSeS QLEDs based on an inverted top emission QLED (ITQLED) structure by newly introducing a “hole‐suppressing interlayer” are demonstrated. The green‐emitting ITQLEDs with the hole‐suppressing interlayer exhibit a maximum current efficiency of 15.1–21.6 cd A?1 and the maximum luminance of 17 400–38 800 cd m?2, which outperform the recently reported InP‐based QLEDs. The operational lifetime is also increased when the hole‐suppressing interlayer is adopted. These superb QLED performances originate not only from the enhanced light‐outcoupling by the top emission structure but also from the improved electron–hole balance by introducing a hole‐suppressing interlayer which can control the hole injection into QDs.  相似文献   
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