Modification of ultra low-k dielectric films by O₂ and CO₂ plasmas

Low-k materials developed for ULSI interconnects should have sufficient resistance to processing plasma. CO2 plasma is being considered as a promising candidate for low damage photoresist ash and as a surface activation chemistry for self-assembled monolayers and atomic layer deposition on low-k materials. This article explores the interaction of two organosilicate (OSG) based low-k materials with different k-values (OSG2.4 and OSG2.2) with CO2 plasma in both CCP and ICP-remote plasma chambers. Time dependent exposure of the materials to CO2 plasma revealed quick and effective sealing of OSG2.4 surface whereas it takes longer time for OSG2.2. The sealing reduces further plasma damage and leads to accumulation of CO2 in the pores of both materials. The same behavior occurs in ICP-remote plasma but without a complete sealing of the surface. This suggests the important role of ion bombardment. Damage to low-k by conventional O-2 plasma was studied alongside and it was found that for t 60 s. Furthermore, lesser time exposure to CO2 plasma was investigated with respect to source power at constant pressure and it was discovered that damage although small, increases with varying source power

Towards Interactive Image Inpainting via Sketch Refinement

One tough problem of image inpainting is to restore complex structures in the corrupted regions. It motivates interactive image inpainting which leverages additional hints, e.g., sketches, to assist the inpainting process. Sketch is simple and intuitive to end users, but meanwhile has free forms with much randomness. Such randomness may confuse the inpainting models, and incur severe artifacts in completed images. To address this problem, we propose a two-stage image inpainting method termed SketchRefiner. In the first stage, we propose using a cross-correlation loss function to robustly calibrate and refine the user-provided sketches in a coarse-to-fine fashion. In the second stage, we learn to extract informative features from the abstracted sketches in the feature space and modulate the inpainting process. We also propose an algorithm to simulate real sketches automatically and build a test protocol with different applications. Experimental results on public datasets demonstrate that SketchRefiner effectively utilizes sketch information and eliminates the artifacts due to the free-form sketches. Our method consistently outperforms the state-of-the-art ones both qualitatively and quantitatively, meanwhile revealing great potential in real-world applications. Our code and dataset are available

Net Phosphorus Requirements of Dorper×Thin-tailed Han Crossbred Ram Lambs

A comparative slaughter trial was conducted to estimate the phosphorus (P) requirement for maintenance and growth of crossbred lambs of Dorper with a Chinese indigenous sheep breed, thin-tailed Han sheep. Thirty-five Dorper×thin-tailed Han crossbred, noncastrated ram lambs (20.3±0.22 kg of shrunk body weight (SBW)) were used. Seven lambs were randomly chosen and slaughtered at 20 kg SBW as the baseline group for measuring initial body composition. Another seven lambs were also randomly chosen and offered a pelleted mixed diet for ad libitum intake and slaughtered at 28 kg SBW. The remaining 21 sheep were randomly divided into 3 groups with 7 sheep each and subject to the same diet of either 70 or 40% of ad libitum intake. The 3 groups were slaughtered when the sheep fed ad libitum reached 35 kg of SBW. Body P contents were determined after slaughter. The results showed that the net P requirement for maintenance was 30.0 mg/kg of empty body weight (EBW) or 23.4 mg/kg body weight (BW), and the P requirement for growth decreased from 5.3 to 5.0 g/kg of EBW gain as the lamb grew from 20 to 35 kg. The net P requirement for growth of Dorper×thin-tailed Han crossbred ram lambs was lower than that of sheep adopted by the American nutritional system

Mechanism of Degradation of the Properties of Recycled Plaster Mixed Aluminate Cement

This manuscript investigates the degradation of the properties of recycled plaster-mixed aluminate cement (RAP) and analyzes its degradation mechanism by DSC/TG and SEM. The results showed that the setting time of RAP was shortened due to the fast formation of recycled ettringite (AFt) and its strength was decreased relative to the pure recycled plaster (RP) in the absence of aluminate cement. Different from the properties of RP and RAP, the hydration of commercial plaster was slowed down by the addition of aluminate cement for its low hydration rate, and its strength was increased with respect to the pure commercial plaster (CP) without aluminate cement. Therefore, the properties of RP and RAP could be seen to decrease in relation to CP and commercial plaster mixed aluminate cement (CAP). The SEM and DSC/TG analyses confirm the presence of cluster and fine crystals and noncementing AH3 in RAP, which demonstrates its degradation of properties

Investigation on the Deterioration Mechanism of Recycled Plaster

The deterioration mechanism of recycled plaster (R-P) was studied. The large specific surface area (SSA), improper preparation temperature, increased water requirement of R-P, and microstructure of its hardened body were analyzed by particle size distribution (PSD), Blaine method, differential scanning calorimetry (DSC), scanning electron microscopy (SEM), and nitrogen adsorption porosimetry. The results indicated that the properties of R-P were deteriorated, but its strength decreases from 50% at the same manufacturing process to 30%–40% at similar specific surface area. The analysis shows that the large SSA, poor morphology, narrow PSD, and increased internal detects give rise to increase of water requirement. In addition, the deterioration properties are caused by unsuitable temperature of preparation, loose structure, and large average pore diameter in hardened R-P as well

Net protein and metabolizable protein requirements for maintenance and growth of early-weaned Dorper crossbred male lambs

Abstract Background Dorper is an important breed for meat purpose and widely used in the livestock industry of the world. However, the protein requirement of Dorper crossbred has not been investigated. The current paper reports the net protein (NP) and metabolizable protein (MP) requirements of Dorper crossbred ram lambs from 20 to 35 kg BW. Methods Thirty-five Dorper × thin-tailed Han crossbred lambs weaned at approximately 50 d of age (20.3 ± 2.15 kg of BW) were used. Seven lambs of 25 kg BW were slaughtered as the baseline animals at the start of the trial. An intermediate group of seven randomly selected lambs fed ad libitum was slaughtered at 28.6 kg BW. The remaining 21 lambs were randomly divided into three levels of dry matter intake: ad libitum or 70% or 40% of ad libitum intake. Those lambs were slaughtered when the lambs fed ad libitum reached 35 kg BW. Total body N and N retention were measured. Results The daily NP and MP requirements for maintenance were 1.89 and 4.52 g/kg metabolic shrunk BW (SBW0.75). The partial efficiency of MP utilization for maintenance was 0.42. The NP requirement for growth ranged from 12.1 to 43.5 g/d, for the lambs gaining 100 to 350 g/d, and the partial efficiency of MP utilization for growth was 0.86. Conclusions The NP and MP requirements for the maintenance and growth of Dorper crossbred male lambs were lower than the recommendations of American and British nutritional systems

Hyperspectral and Multispectral Image Fusion via Nonlocal Low-Rank Tensor Decomposition and Spectral Unmixing

Hyperspectral (HS) imaging has shown its superiority in many real applications. However, it is usually difficult to obtain high-resolution (HR) HS images through existing imaging techniques due to the hardware limitations. To improve the spatial resolution of HS images, this article proposes an effective HS-multispectral (HS-MS) image fusion method by combining the ideas of nonlocal low-rank tensor modeling and spectral unmixing. To be more precise, instead of unfolding the HS image into a matrix as done in the literature, we directly represent it as a tensor, then a designed nonlocal Tucker decomposition is used to model its underlying spatial-spectral correlation and the spatial self-similarity. The MS image serves mainly as a data constraint to maintain spatial consistency. To further reduce the spectral distortions in spatial enhancement, endmembers, and abundances from the spectral are used for spectral regularization. An efficient algorithm based on the alternating direction method of multipliers (ADMM) is developed to solve the resulting model. Extensive experiments on four HS image data sets demonstrate the superiority of the proposed method over several state-of-theart HS-MS image fusion methods

Self-Assembly of Single-Polymer-Tethered Nanoparticle Amphiphiles upon Varying Tail Length

We systematically investigated the roles of tail length on the self-assembly of shape amphiphiles composed of a hydrophobic polymer chain (tail) and a hydrophilic nanoparticle in selective solvent using Brownian dynamics simulations. The shape amphiphiles exhibited a variety of self-assembled aggregate morphologies which can be tuned by changing tail length (n) in combination with amphiphile concentration (φ) and system temperature (T*). Specifically, at high φ with T*=1.4, the morphology varied following the sequence “spheres → cylinders → vesicles” upon increasing n, agreeing well with experimental observations. At low φ with T*=1.4 or at high φ with T*=1.2, the morphology sequence becomes “spheres or spheres and cylinders mixture → cylinders → vesicles → spheres” upon increasing n, which has not been found experimentally. Two morphological phase diagrams depending on n and φ were constructed for T*=1.4 and 1.2, respectively. The rich phase behaviors on varying tail length could provide the feasible routes to fabricate target aggregate morphologies in various applications, especially for the vesicles with tunable thickness of membranes that are crucial in drug and gene delivery

Cross-scale process quality control of variable polarity plasma arc welding based on predefined temperature field

This study investigates the underlying causes of Variable Polarity Plasma Arc Welding (VPPAW) spatial positional instability and its adverse impact on weld seam quality. Microstructural analysis reveals that the primary cause of poor transverse mechanical properties is the asymmetric distribution of grains. Through the study of heat and mass transfer in the molten pool, it was found that the asymmetric flow of molten metal under the influence of gravity is the main factor leading to uneven temperature distribution and asymmetric grain distribution in the weld pool. A novel approach based on a predefined temperature field is proposed to regulate the weld pool's stability and welding quality. The implementation of the predefined temperature field effectively improves VPPAW weld pool flow, leading to enhanced temperature distribution and grain size and distribution. These findings provide a theoretical foundation and valuable engineering recommendations for achieving high-quality spatial position welding in VPPAW