Progress towards high-performance, steady-state spherical torus

The next generation of thermal interface materials (TIMs) are currently being developed to meet the increasing demands of high-powered semiconductor devices. In particular, a variety of nanostructured materials, such as carbon nanotubes (CNTs), are interesting due to their ability to provide low resistance heat transport from device-to-spreader and compliance between materials with dissimilar coefficients of thermal expansion (CTEs), but few application-ready configurations have been produced and tested. Recently, we have undertaken major efforts to develop functional nanothermal interface materials (nTIMs) based on short, vertically aligned CNTs grown on both sides of a thin interposer foil and interfaced with substrate materials via metallic bonding. A high-precision 1D steady-state test facility has been utilized to measure the performance of nTIM samples, and more importantly, to correlate performance to the controllable parameters. In this paper, we describe our material structures and the myriad permutations of parameters that have been investigated in their design. We report these nTIM thermal performance results, which include a best to-date thermal interface resistance measurement of 3.5 mm2 K/W, independent of applied pressure. This value is significantly better than a variety of commercially available, high-performance thermal pads and greases we tested, and compares favorably with the best results reported for CNT-based materials in an application-representative setting.

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Comparison of Plasma, Epithelial Lining Fluid, and Alveolar Macrophage Concentrations of Solithromycin (CEM-101) in Healthy Adult Subjects

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00766-12 ◽

2012 ◽

Vol 56 (10) ◽

pp. 5076-5081 ◽

Cited By ~ 39

Author(s):

Keith A. Rodvold ◽

Mark H. Gotfried ◽

J. Gordon Still ◽

Kay Clark ◽

Prabhavathi Fernandes

Keyword(s):

Steady State ◽

High Performance ◽

Healthy Adult ◽

Plasma Concentrations ◽

Epithelial Lining ◽

Time Curve ◽

Epithelial Lining Fluid ◽

Once Daily ◽

Drug Concentrations ◽

The Mean

ABSTRACTThe steady-state concentrations of solithromycin in plasma were compared with concomitant concentrations in epithelial lining fluid (ELF) and alveolar macrophages (AM) obtained from intrapulmonary samples during bronchoscopy and bronchoalveolar lavage (BAL) in 30 healthy adult subjects. Subjects received oral solithromycin at 400 mg once daily for five consecutive days. Bronchoscopy and BAL were carried out once in each subject at either 3, 6, 9, 12, or 24 h after the last administered dose of solithromycin. Drug concentrations in plasma, ELF, and AM were assayed by a high-performance liquid chromatography-tandem mass spectrometry method. Solithromycin was concentrated extensively in ELF (range of mean [± standard deviation] concentrations, 1.02 ± 0.83 to 7.58 ± 6.69 mg/liter) and AM (25.9 ± 20.3 to 101.7 ± 52.6 mg/liter) in comparison with simultaneous plasma concentrations (0.086 ± 0.070 to 0.730 ± 0.692 mg/liter). The values for the area under the concentration-time curve from 0 to 24 h (AUC0–24values) based on mean and median ELF concentrations were 80.3 and 63.2 mg · h/liter, respectively. The ratio of ELF to plasma concentrations based on the mean and median AUC0–24values were 10.3 and 10.0, respectively. The AUC0–24values based on mean and median concentrations in AM were 1,498 and 1,282 mg · h/L, respectively. The ratio of AM to plasma concentrations based on the mean and median AUC0–24values were 193 and 202, respectively. Once-daily oral dosing of solithromycin at 400 mg produced steady-state concentrations that were significantly (P< 0.05) higher in ELF (2.4 to 28.6 times) and AM (44 to 515 times) than simultaneous plasma concentrations throughout the 24-h period after 5 days of solithromycin administration.

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Optimizing steady-state visual evoked potential classifiers for high performance and low computational costs in brain-computer interfacing

10.1109/bibe52308.2021.9635303 ◽

2021 ◽

Author(s):

Rasmus Leck Kaeseler ◽

Lotte N. S. Andreasen Struijk ◽

Mads Jochumsen

Keyword(s):

Steady State ◽

High Performance ◽

Visual Evoked Potential ◽

Evoked Potential ◽

Computational Costs ◽

Brain Computer Interfacing ◽

Computer Interfacing ◽

Visual Evoked

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Efficient Thermal Analysis of Lab-Grown Diamond Heat Spreaders

10.1115/ipack2021-73017 ◽

2021 ◽

Author(s):

Zihao Yuan ◽

Tao Zhang ◽

Jeroen Van Duren ◽

Ayse K. Coskun

Keyword(s):

Steady State ◽

Real World ◽

High Performance ◽

Silicon Layer ◽

Maximum Temperature ◽

Cooling Performance ◽

Thermal Models ◽

Heat Spreaders ◽

Transient Simulations ◽

Transient Thermal

Abstract Lab-grown diamond heat spreaders are becoming attractive solutions compared to traditional copper heat spreaders due to their high thermal conductivity, the ability to directly bond them on silicon, and allow for an ultra-thin silicon layer. Researchers have developed various thermal models and prototypes of lab-grown diamond heat spreaders to evaluate their cooling performance and heat spreading ability. The majority of existing thermal models are built using finite-element method (FEM) based simulators such as COMSOL and ANSYS. However, such commercial simulators are computationally expensive and lead to long solution times along with large memory requirements. These limitations make commercial simulators unsuitable for evaluating numerous design alternatives or runtime scenarios for real-world high-performance processors. Because of this modeling challenge, none of the existing works have evaluated the thermal behavior of lab-grown diamond heat spreaders on real-world high-performance processors running realistic application benchmarks. Recently, we have developed a parallel compact thermal simulator, PACT, that is able to carry out fast and accurate steady-state and transient thermal simulations and can be extended to support emerging integration and cooling technologies. In this paper, we use PACT to evaluate the steady-state and transient cooling performance of lab-grown diamond heat spreaders against traditional copper heat spreaders on various real-world high-performance processors (e.g., Intel i7 6950X, IBM Power9, and PicoSoC). By using PACT with architectural performance and power simulators such as Sniper and McPAT, we are able to run transient simulations with realistic benchmarks. Simulation results show that lab-grown diamond heat spreaders achieve maximum temperature and thermal gradient reductions of up to 26.73 °C and 13.75 °C when compared to traditional copper heat spreaders, respectively. The maximum steady-state and transient simulation times of PACT for the real-world high-performance chips and realistic applications used in our experiments are 259 s and 22 min, respectively.

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8-Hydroxylation and Glucuronidation of Mirtazapine in Japanese Psychiatric Patients: Significance of the Glucuronidation Pathway of 8-Hydroxy-Mirtazapine

Pharmacopsychiatry ◽

10.1055/a-0918-6408 ◽

2019 ◽

Vol 52 (05) ◽

pp. 237-244

Author(s):

Masataka Shinozaki ◽

Jason Pierce ◽

Yuki Hayashi ◽

Takashi Watanabe ◽

Taro Sasaki ◽

...

Keyword(s):

Body Weight ◽

Steady State ◽

Plasma Levels ◽

High Performance ◽

Psychiatric Patients ◽

Plasma Concentrations ◽

Steady State Concentration ◽

Chain Reaction ◽

Polymerase Chain ◽

State Concentration

Abstract Introduction To investigate the metabolism of mirtazapine (MIR) in Japanese psychiatric patients, we determined the plasma levels of MIR, N-desmethylmirtazapine (DMIR), 8-hydroxy-mirtazapine (8-OH-MIR), mirtazapine glucuronide (MIR-G), and 8-hydroxy-mirtazapine glucuronide (8-OH-MIR-G). Methods Seventy-nine Japanese psychiatric patients were treated with MIR for 1–8 weeks to achieve a steady-state concentration. Plasma levels of MIR, DMIR, and 8-OH-MIR were determined using high-performance liquid chromatography. Plasma concentrations of MIR-G and 8-OH-MIR-G were determined by total MIR and total 8-OH-MIR (i. e., concentrations after hydrolysis) minus unconjugated MIR and unconjugated 8-OH-MIR, respectively. Polymerase chain reaction was used to determine CYP2D6 genotypes. Results Plasma levels of 8-OH-MIR were lower than those of MIR and DMIR (median 1.42 nmol/L vs. 92.71 nmol/L and 44.96 nmol/L, respectively). The plasma levels (median) of MIR-G and 8-OH-MIR-G were 75.00 nmol/L and 111.60 nmol/L, giving MIR-G/MIR and 8-OH-MIR-G/8-OH-MIR ratios of 0.92 and 59.50, respectively. Multiple regression analysis revealed that smoking was correlated with the plasma MIR concentration (dose- and body weight–corrected, p=0.040) and that age (years) was significantly correlated with the plasma DMIR concentration (dose- and body weight–corrected, p=0.018). The steady-state plasma concentrations of MIR and its metabolites were unaffected by the number of CYP2D6*5 and CYP2D6*10 alleles. Discussion The plasma concentration of 8-OH-MIR was as low as 1.42 nmol/L, whereas 8-OH-MIR-G had an approximate 59.50 times higher concentration than 8-OH-MIR, suggesting a significant role for hydroxylation of MIR and its glucuronidation in the Japanese population.

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Ultrathin bismuth nanosheets as an efficient polysulfide catalyst for high performance lithium–sulfur batteries

Journal of Materials Chemistry A ◽

10.1039/c9ta11079h ◽

2020 ◽

Vol 8 (1) ◽

pp. 149-157 ◽

Cited By ~ 6

Author(s):

Hongfei Xu ◽

Shubin Yang ◽

Bin Li

Keyword(s):

Steady State ◽

High Performance ◽

Electrochemical Methods ◽

Lithium Sulfur Batteries ◽

Lithium Sulfur

Ultrathin polycrystalline bismuth (2D-Bi) nanosheets is developed as the multifunctional electrocatalyst for polysulfide conversion. And an in-depth understanding of the distinctive electrocatalysis mechanism of 2D-Bi is revealed by steady-state and dynamic electrochemical methods.

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