Magnetic field-enhanced photocatalytic nitrogen fixation over defect-rich ferroelectric Bi2WO6

Photocatalytic N₂ fixation is a promising and sustainable manufacturing process of ammonia (NH₃); however, the NH₃ production rate by this method is very low, thus severely restricting further application of this sustainable technology. Therefore, developing an efficient photocatalyst for N₂ fixation under mild conditions is urgently required. Herein, ferroelectric Bi₂WO₆ materials with different surface oxygen defects were prepared, and the concentration of corresponding defects was controlled by adjusting the thermal reduction time. The abundant oxygen defects in Bi₂WO₆ can provide more reactive sites to promote the effective adsorption of N₂, and the photogenerated charge carrier can be efficiently separated benefiting from the internal electric field. These would weaken the N₂ triple bond and reduce the activation energy barrier for the conversion of N₂ to NH₃ under mild conditions. In the absence of sacrificial agents and cocatalysts, the optimized Bi₂WO₆ with oxygen defects shows an indigenous NH₃ yield of 132.175 μmol·g^-1·L^-1·h^-1, which is more than two times higher than that of the original Bi₂WO₆. Surprisingly, the Bi₂WO₆ with oxygen defects produced more than eight times NH₃ (471.13 μmol·g^-1·L^-1·h^-1) than that of the original Bi₂WO₆ when assisted by an external magnetic field, thus providing a new perspective for further enhancing the N₂ fixation performance.     

Zinc doped Fe2O3 for boosting Electrocatalytic Nitrogen Fixation to ammonia under mild conditions

Artificial nitrogen fixation is emerging as a promising approach for synthesis of ammonia at mild conditions. Inspired by biological nitrogen fixation based on bacteria containing iron, zinc doped Fe₂O₃ nanoparticles are proposed as an efficient and earth abundant electrocatalyst for converting N₂ to NH₃. In neutral media, it achieves a maximum Faradaic efficiency (FE) of 10.4% and a large NH₃ yield rate of 15.1 μg h^?1 mg^?1_cat. at ?0.5 V vs. reversible hydrogen electrode. This catalyst also exhibits excellent selectivity and stability. Theoretical calculations suggest the reaction follows the associative enzymatic mechanism and it has a barrier of as low as 0.68 eV.     

Tracking the mind during reading: The influence of past, present, and future words on fixation durations.

Reading requires the orchestration of visual, attentional, language-related, and oculomotor processing constraints. This study replicates previous effects of frequency, predictability, and length of fixated words on fixation durations in natural reading and demonstrates new effects of these variables related to 144 sentences. Such evidence for distributed processing of words across fixation durations challenges psycholinguistic immediacy-of-processing and eye-mind assumptions. Most of the time the mind processes several words in parallel at different perceptual and cognitive levels. Eye movements can help to unravel these processes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

羟基磷灰石涂层人工关节的应用研究

采用人工合成高纯度的羟基磷灰石粉末，喷涂在具有注册证的钛合金和钴铬钼合金人工关节上。通过生物学基础检测、动物实验和临床试用，证明所制作的各种羟基磷灰石涂层人工关节，能诱发骨质生长，起生物固定作用，对治疗丧失功能的骨胳效果甚佳。     

骨折内固定材料的研究进展

传统的骨折内固定材料在临床应用过程中出现了许多亟待解决的问题,如应力遮挡等,这些问题不但与材料的设计有关,而且与所采用的材料有密切关系.在概述骨折内固定材料的发展历史及目前所存在的主要问题的基础上,阐述了骨折内固定材料近些年来的新进展及今后的发展前景.     

Plasticity of feature-based selection in triple-conjunction search.

Two experiments examined the disruption of feature-based selection in triple-conjunction search at multiple target transfers. In Experiment 1, after 10 training sessions, a new target possessing previous distractor features was introduced. This produced disruption in RT and fixation number, but no disruption in feature-based selection. Specifically, there was a tendency to fixate objects sharing the target's contrast polarity and shape and this did not change even upon transfer to the new target. In Experiment 2, 30 training sessions were provided with three target transfers. At the first transfer, the results replicated Experiment 1. Subsequent transfers did not produce disruption on any measure. These findings are discussed in terms of strength theory, Guided Search, rule-based approaches to perceptual learning, and the area activation model. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

微波在免疫组织化学中的应用

本文综述微波技术在免疫组织化学中的应用两头及其进展，着重介绍了微波在组织固定、抗原恢复和免疫染色方面的应用，并对微波免疫组织化学的应用前景进行了展望 。     

The ability of eye-tracking metrics to classify and predict the perceived driving workload

Traffic safety is directly related to the mental and physical condition of the driver. Performing regular secondary tasks while driving is an additional activity that dissipates attention and adds to the drivers' workload. Identifying driver fatigue and workload based on gaze behavior is one way to ensure a safe driving experience. The purpose of this paper is to classify and predict driving perceived workload using a set of eye-tracking metrics (gaze fixation, duration, pointing, and pupil diameter). The ability of eye-tracking metrics to predict driving workload has been investigated. As a result, frustration, performance, and temporal load showed a correlation with gaze metrics. Gaze point, duration, fixation, and pupil diameter significantly influence driving workload.Relevance to industry: Results will supply the specialists in eye-tracking/sensor technologies and traffic safety with new knowledge to improve the design of the driving performance and safety monitoring systems and efficiency of the driving process.     

Chemical interactions between soil N and alkaline-hydrolysing N fertilizers

Chemical interactions between soil N and alkaline-hydrolysing N fertilizers labelled with¹⁵N were studied in the laboratory using twelve-irradiated soils. Fertilizer was recovered in the soil organic N fraction via the process of NH₃ fixation. NH₃ fixation at day 7 varied from 1.8 to 4.6% of the N added as aqua ammonia at 1000 mg kg^–1 soil. The amount of NH₃ fixed increased with increasing rates of application of NH_3(aq) and urea. The rate of NH₃ fixation decreased with time, with more than 55% of the total NH₃ fixation in 28 days occurring in the first week following application of 2000 mg urea-N kg^–1 soil. Soil pH and NH₃ fixation varied in response to N source, and increased in the order of di-ammonium phosphate 3 fixation, resulting in the release of unlabelled ammonium (deamination) and a real added nitrogen interaction in all but two of the soils studied. The release of NH ₄ ⁺ initially increased up to a pH of 7.5, was inhibited between pH 8.5 and 9.0, but increased thereafter. The balance (N_bal) between NH₃ fixation and deamination was either positive or negative, depending on the pH of the fertilized soil, which was directly related to N source and concentration for a given soil.