To rationalize the marked difference in the energy conversion efficiency of dye sensitized solar cells (DSSCs) based on organic dyes 1 and 2 different only in their p spacer, density functional theory (DFT) and time-dependent DFT calculations of the geometries, electronic structures and absorption spectra of the organic dyes before and after binding to titanium oxide were carried out. These enable us to determine factors such as dipole moments associated with the open-circuit photovoltage (V oc ), and to quantify parameters such as the light harvesting efficiency, the electron injection efficiency associated with the short-circuit photocurrent density (J sc ). The results reveal that compared to 2 with a thiazole spacer, 1 with a thiophene spacer could cause a red shift of the absorption spectrum, increase the oscillator strength and improve the driving force for electron injection, thus leading to the larger J sc , in good agreement with experimental data. As for V oc , our results stress that apart from the generally emphasized vertical dipole moment of the dyes pointing outward from the semiconductor surface, the number of photoinjected electrons from the dye to the semiconductor is also crucial to obtain high performance dyes with high V oc . After justifying the reliability of the quantum-chemical methods, we designed another four dyes with different p spacers to screen more efficient organic dyes. Fortunately, taking 1 as reference, we find that dye 4 with a thienothiophene spacer displays an enhanced J sc and V oc , indicating that it will be a more efficient diarylamine-fluorene-based organic dye used in DSSCs, which will play a theoretical guiding role in the design and synthesis of new organic dyes.

The utilization of HSO, produced using SO from nonferrous metal smelting flue gas as a source of S, is extremely restricted due to Hg contamination; therefore, there is great demand to remove Hg from smelting flue gas. Although the ability of Cu/TiO to capture Hg is excellent, its resistance to HO and SO is very poor. In this study, Cu/TiO was treated with HS to improve its resistance to HO and SO for capturing Hg. The chemical adsorption of Hg on Cu/TiO was primarily through the HgO route, which was almost suppressed by HO and SO due to the transformation of CuO into CuSO. Besides the HgO route, the HgS route also contributed to the chemical adsorption of Hg on modified Cu/TiO. As the CuS on modified Cu/TiO was inert to HO and SO, the chemical adsorption of Hg on modified Cu/TiO through the HgS route was barely inhibited. Meanwhile, the HgS route was predominant in the chemical adsorption of Hg on modified Cu/TiO. Therefore, modified Cu/TiO exhibited an excellent resistance to HO and SO, and its Hg capture capacity from simulated flue gas was up to 12.7 mg g at 100 °C.

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The proliferation of mobile devices, ubiquitous internet, and cloud computing has sparked a new era of Internet of Things (IoT), thus allowing researchers to create applicationspecific solutions based on the interconnection between physical objects and the internet. Recently, wearable devices are rapidly emerging and forming a new segment-"Wearable IoT (WIoT)" due to their capability of sensing, computing and communication. Future generations of WIoT promise to transform the healthcare sector, wherein individuals are seamlessly tracked by wearable sensors for personalized health and wellness information-body vital parameters, physical activity, behaviors, and other critical parameters impacting quality of daily life. This paper presents an effort to conceptualize WIoT in terms of their design, function, and applications. We discuss the building blocks of WIoT-including wearable sensors, internet-connected gateways and cloud and big data support-that are key to its future success in healthcare domain applications. We also present a new system science for WIoT that suggests future directions, encompassing operational and clinical aspects.