绿松石结构的致密性对其颜色量化研究的影响

绿松石的结构致密性对其颜色量化研究工作存在重要影响。采用国际公认的色度学变量CIE 1976色差(ΔE)来表征绿松石样品在特定区域内颜色的不均一性,通过静水称重法和原子力显微镜(AFM)来表征结构致密性的体相和表相特征。结果发现,质地疏松绿松石存在较大色差、较大的表面粗糙度及较小的相对密度。激光剥蚀电感耦合等离子质谱仪(LA-ICP-MS)研究绿松石成分显示,疏松绿松石样品中致色元素含量呈现较大的测量不确定性,存在很严重的随激光剥蚀时间延长而迅速衰减的现象,而致密绿松石样品并无此现象。出土疏松绿松石样品的受沁程度和色差也明显大于致密样品。相对而言,高致密性绿松石具有相对密度较大、表面平滑度较高、颜色分布较为均一、致色元素分布较为规律、抗污染能力较强等优良特征。因此,在后续绿松石颜色量化分级工作当中,对致密性进行严格定量显得尤为必要。     

Temporarily Expanding the Boundaries of the Self: Motivations for Entering the Story World and Implications for Narrative Effects

A wide variety of motivations for engaging with narratives have been proposed and studied. We propose that underlying these motivations is another, more fundamental motivation. Our premise is that maintenance, defense, and regulation of the personal and social self in daily life are demanding both emotionally and cognitively. Moreover, any individual self is constrained by capability, situation, and social role. Stories and identification with story characters provide a means individuals may use for temporary relief from the task of self‐regulation and from the limitations of individual personal and social identities. Existing supportive research is acknowledged and implications explored, concerning contexts in which story involvement will be particularly attractive and possible impacts on attitudes and acceptance of out‐groups including stigmatized others.     

Virtual network embedding: ensuring correctness and optimality by construction using model transformation and integer linear programming techniques

Software and Systems Modeling - Virtualization technology allows service providers to operate data centers in a cost-effective and scalable manner. The data center network (substrate network) and...     

Why are Tailored Messages More Effective? A Multiple Mediation Analysis of a Breast Cancer Screening Intervention

Past research has found that tailoring increases the persuasive effectiveness of a message. However, the observed effect has been small and the explanatory mechanism remains unknown. To address these shortcomings, a tailoring software program was created that personalized breast cancer screening pamphlets according to risk, health belief model constructs, and visual preference. Women aged 40 and older (N = 119) participated in a 2 (Tailored vs. Stock Message) × 2 (Charts/Graphs vs. Illustrated Visuals) × 3 (Nested Replications of the Visuals) experiment. Participants provided with tailored illustrated pamphlets expressed greater breast cancer screening intentions than those provided with other pamphlets. In a test of 10 different mediators, perceived message relevance was found to fully mediate the Tailoring × Visual interaction.     

Data Work: How Energy Advisors and Clients Make IoT Data Accountable

We present fieldwork findings from the deployment of an interactive sensing system that supports the work of energy advisors who give face-to-face advice to low-income households in the UK. We focus on how the system and the data it produced are articulated in the interactions between professional energy advisors and their clients, and how they collaboratively anticipate, rehearse, and perform data work. In addition to documenting how the system was appropriated in advisory work, we elaborate the ‘overhead cost’ of building collaborative action into connected devices and sensing systems, and the commensurate need to support discrete workflows and accountability systems to enable the methodical incorporation of the IoT into collaborative action. We contribute an elaboration of the social, collaborative methods of data work relevant to those who seek to design and study collaborative IoT systems.     

DOA estimation of wideband sources without estimating the number of sources

In this paper, we propose a new technique to estimate wideband source directions from the sensor snapshots without requiring to know the number of sources present in the scenario. This work is motivated by the fact that the existing model order estimation (number of sources) techniques for wideband source scenario are either inaccurate or computationally expensive. Direction-of-arrival (DOA) estimation is realized using a beamformer framework which imposes nulls in the spatial spectrum along the source directions. The null width along the frequency axis is widened by introducing a new data dependent term into the optimization problem, thus achieving wideband capability. Furthermore, the temporal processing of the data snapshots drastically reduces the number of snapshots required for wideband DOA estimation. The effectiveness of the proposed formulation is studied with simulated experiments.     

Ultrasonic spray pyrolysis synthesis of Ag/TiO2 nanocomposite photocatalysts for simultaneous H2 production and CO2 reduction

Simultaneous photocatalytic hydrogen production and CO₂ reduction (to form CO and CH₄) from water using methanol as a hole scavenger were investigated using silver-modified TiO₂ (Ag/TiO₂) nanocomposite catalysts. A simple ultrasonic spray pyrolysis (SP) method was used to prepare mesoporous Ag/TiO₂ composite particles using TiO₂ (P25) and AgNO₃ as the precursors. The material properties and photocatalytic activities were compared with those prepared by a conventional wet-impregnation (WI) method. It was found that the samples prepared by the SP method had a larger specific surface area and a better dispersion of Ag nanoparticles on TiO₂ than those prepared by the WI method, and as a result, the SP samples showed much higher photocatalytic activities toward H₂ production and CO₂ reduction. The optimal Ag concentration on TiO₂ was found to be 2 wt%. The H₂ production rate of the 2% Ag/TiO₂–SP sample exhibited a six-fold enhancement compared with the 2% Ag/TiO₂–WI sample and a sixty-fold enhancement compared with bare TiO₂. The molar ratio of H₂ and CO in the final products can be tuned in the range from 2 to 10 by varying the reaction gas composition, suggesting a viable way of producing syngas (a mixture of H₂ and CO) from CO₂ and water using the prepared Ag/TiO₂ catalysts with energy input from the sun.     

Measuring and comparing service quality metrics through social media analytics: a case study

This paper proposes a framework of using social media analytics to help study service quality. A case study was conducted to collect and analyze a data set which included nearly half million tweets related to two of the largest supermarkets in the United States: Walmart and Kmart. The results illustrate how businesses can leverage external open data to complement the traditional survey-based approaches in order to better understand and measure their service quality metrics by studying the online opinions of their customers.     

Nano and Microtechnologies for the Study of Magnetotactic Bacteria

Magnetotactic bacteria (MTB) naturally synthesize magnetic nanoparticles that are wrapped in lipid membranes. These membrane‐bound particles, which are known as magnetosomes, are characterized by their narrow size distribution, high colloidal stability, and homogenous magnetic properties. These characteristics of magnetosomes confer them with significant value as materials for biomedical and industrial applications. MTB are also a model system to study key biological questions relating to formation of bacterial organelles, metal homeostasis, biomineralization, and magnetoaerotaxis. The similar size scale of nano and microfluidic systems to MTB and ease of coupling to local magnetic fields make them especially useful to study and analyze MTB. In this Review, a summary of nano‐ and microtechnologies that are developed for purposes such as MTB sorting, genetic engineering, and motility assays is provided. The use of existing platforms that can be adapted for large‐scale MTB processing including microfluidic bioreactors is also described. As this is a relatively new field, future synergistic research directions coupling MTB, and nano‐ and microfluidics are also suggested. It is hoped that this Review could start to bridge scientific communities and jump‐start new ideas in MTB research that can be made possible with nano‐ and microfluidic technologies.