CCUS in a net-zero U.S. power sector: Policy design,rates, and project finance

Carbon capture utilization and storage is an important technology option to rapidly and profoundly decarbonize the power sector, but will not deploy without substantial incentives or regulation. Assessment of U.S. policy options reveals that current incentives only partially close the finance gap and are most sensitive to fuel type and ownership structure. Recent proposed legislation would in some designs attract private investment for many projects, leading to widespread deployment of CCUS in the power sector. Additional constraints and concerns (including technology options and presence of CO₂ infrastructure) could play an important secondary role. This study discusses the specific US incentive policies that can provide investors and lenders with net cash flows that are adequate to attract private capital to CCUS power projects in the US.     

大型自动埋弧焊成套设备的研究

本文介绍了一种结构新颖的埋弧焊成套设备,并就埋弧焊成套设备中的一些主要部件作了分析说明。该设备采用的平移式横梁结构、三点式九滚轮导轨装置以及焊缝自动跟踪装置,对满足同平面内多道长焊缝的焊接有独到之处。     

中国的钛工业概况

对近年来轻水反应堆用锆合金材料的发展及其应用研究中一些主要技术问题和标准要求进行了综合述评。     

筒形件强力旋压新技术--浮动芯模法

提出了一种新的旋压方法－浮动芯模法。该方法采用的芯模长度尺寸较小,两端不固定加工,制造和安装非常容易。由于该方法是采用旋轮不动,工件做轴向运动,故解决了正旋所带来的工件扭曲的问题。此法用于加工长管类件,更显示出它的优越性,对改善管类件的加工具有重要的意义。     

使用人工神经网络对强力旋压有限元模拟进行参数预选

在筒形件强力旋压领域内，介绍了使用人工神经网络的手段，在MARC有限元模拟的前处理中实现参数预选的方法。作为与有限元模拟相结合的旋压智能化设计的一项关键技术，能够达到减少有限元模拟的误差和工作量的目的。     

EXPERIMENTAL STUDY ON MIXING: POWER CONSUMPTION AND DEGREE OF SUSPENSION

An experimental study on mixing, degree of suspension and power consumption in solid-liquid suspensions was done. A system similar to those found in anaerobic fermentation processes of animal manures was used, and an existing mixing equipment was adapted for the study. Power consumption and degree of suspension for both mechanical mixing and mixing by gas was determined. The influence of variables such as geometry, solids concentration, stirrer velocity, and gas velocity was studied, discussed, and compared to data from the literature. Best results were obtained for gas mixing, the power consumption being about one fourth of that required by mechanical agitation. Finally, extended correlations relating Power and Reynolds numbers for mechanical mixing and mixing by gas are proposed.     

电泳涂料

本文介绍了电泳涂料及发展趋势。     

Muscular fatigue and maximum endurance time assessment for male and female industrial workers

A single arm pushing experiment was conducted in an electronic factory in Yantai, China to assess muscular fatigue using the theoretical models of muscular strength and maximum endurance time (MET) developed by Ma et al. (2009). Seventy seven workers, including 38 males and 39 females, participated in the study. The muscular strength of pushing was measured after the subject pushed a stick, with a force of 2.5 kgf, for 0.5, 1.0, 1.5, 2.0, 2.5, and 3.0 min. Fatigue rate was determined based on a regression approach. In addition to the theoretical model, the MET for such a pushing task was also determined using four empirical models in the literature. The results indicated that females were more resistant to muscular fatigue than males in the pushing task. The results of the muscular strength prediction show that the predictability of the muscular strength model is acceptable. The prediction errors for muscular strength for female subjects were significantly lower than those of the male subjects. The predicted MET using the theoretical model, with a group constant k, was highly correlated with those using the empirical models compared in the current study.     

Estimation and forecasting with logarithmic autoregressive conditional duration models: A comparative study with an application

This paper presents a semi-parametric method of parameter estimation for the class of logarithmic ACD (Log-ACD) models using the theory of estimating functions (EF). A number of theoretical results related to the corresponding EF estimators are derived. A simulation study is conducted to compare the performance of the proposed EF estimates with corresponding ML (maximum likelihood) and QML (quasi maximum likelihood) estimates. It is argued that the EF estimates are relatively easier to evaluate and have sampling properties comparable with those of ML and QML methods. Furthermore, the suggested EF estimates can be obtained without any knowledge of the distribution of errors is known. We apply all these suggested methodology for a real financial duration dataset. Our results show that Log-ACD (1, 1) fits the data well giving relatively smaller variation in forecast errors than in Linear ACD (1, 1) regardless of the method of estimation. In addition, the Diebold–Mariano (DM) and superior predictive ability (SPA) tests have been applied to confirm the performance of the suggested methodology. It is shown that the new method is slightly better than traditional methods in practice in terms of computation; however, there is no significant difference in forecasting ability for all models and methods.     

CFD modeling of pilot-scale pump-mixer: Single-phase head and power characteristics

The present work involves single-phase computational fluid dynamics (CFD) simulations of continuous flow pump-mixer employing top-shrouded Rushton turbines with trapezoidal blades. Baffle—impeller interaction has been modeled using sliding mesh and multiple reference frame approaches. Standard k-ε model has been used for turbulence modeling. Several CFD runs representing different combinations of geometric and process parameters have been carried out. Results of CFD simulations have been used to find out two macroscopic performance parameters of pump-mixer—power consumption and head generated by the impeller. The simulation results have been compared with the experimental data obtained on a pilot-scale setup. Good agreement between CFD predictions and experimental results is observed. In most cases, sliding mesh approach is found to perform better than multiple reference frame approach. Details from CFD simulations have been used to have an insight into the pumping action of the impeller.