Perceived Chronic Social Adversity and Suicidal Ideation Among Chinese College Students: The Moderating Role of Hope.

This study aimed to investigate the relations among perceived chronic social adversity, hope and suicidal ideation among Chinese college students. 535 college students completed the Perceived Chronic Social Adversity Questionnaire (PCSAQ), the Suicidal Ideation Scale (SIS), and the Revised Adult Dispositional Hope Scale (RADHS). The results showed that perceived chronic social adversity was positively associated with suicidal ideation, and hope was negatively associated with suicidal ideation. The results also confirmed that hope negatively moderated the relationship between perceived chronic social adversity and suicidal ideation. Further study showed that there was a significant positive relation between perceived chronic social adversity and suicidal ideation under the low hope level, however, there was a non-significant relation between perceived chronic social adversity and suicidal ideation under the high hope level.

Investigation on operational parameters and membrane fouling performance in treating synthetic aquaculture wastewater via forward osmosis with sucrose as draw solution.

Forward osmosis (FO), a membrane separation process driven by a natural concentration gradient, is served as a potential strategy in the aspect of wastewater treatment. In this work, a worthy attempt at aquaculture wastewater treatment using a self-made FO system was conducted, confirming it was a promising approach to treating aquaculture wastewater. Optimization of operational parameters of the FO system, including draw solution (DS) concentration, cross-flow velocity, and DS temperature, was systematically investigated to enhance the running efficiency. Different selected parameters highly influenced the water flux during the single-factor experiments, and the findings indicated that the optimal conditions were DS of 1.5 M, cross-flow velocity of 15 cm/s, and temperature of 32 °C with consideration of FO performance and economical cost. An excellent linear relationship between chemical oxygen demand (COD) changing multiples and operational parameters was obtained from experimental results, offering a great interception performance of organic contamination. On the basis of optimal operating conditions, membrane fouling experiments with different running time were conducted, and the microscopic morphology and element composition of the fouled membrane were also analyzed. The results demonstrated that a layer of cake was coated on the surface of the membrane, and the main elements in the fouling cake included C, O, Na, and S, which were highly determined by the component of the feed solution (FS) and working time. Afterward, the 60-h FO fouled membrane was cleaned under the method which combined hydraulic power and chemical agents, and the water flux recovered to 12.79 Lm-2 h-1, proving a good performance for the recovery of water flux. This investigation showed that employing sucrose as DS was effective for reducing wastewater volume, and it provided an alternative choice and a sustainable way for the separation of organic pollutants from water resources.

Flexible Semiconductor Technologies with Nanoholes-Provided High Areal Coverages and Their Application in Plasmonic-Enhanced Thin Film Photovoltaics.

Mechanical flexibility and advanced light management have gained great attentions in designing high performance, flexible thin film photovoltaics for the realization of building-integrated optoelectronic devices and portable energy sources. This study develops a soft thermal nanoimprint process for fabricating nanostructure decorated substrates integrated with amorphous silicon solar cells. Amorphous silicon (a-Si:H) solar cells have been constructed on nanoholes array textured polyimide (PI) substrates. It has been demonstrated that the nanostructures not only are beneficial to the mechanical flexibility improvement but also contribute to sunlight harvesting enhancement. The a-Si:H solar cells constructed on such nanopatterned substrates possess broadband-enhanced light absorption, high quantum efficiency and desirable power conversion efficiency (PCE) and still experience minimal PCE loss even bending around 180°. The PCE performance without antireflection coatings increases to 7.70% and it improves 40% compared with the planar devices. Although the advantages and feasibility of the schemes are demonstrated only in the application of a-Si:H solar cells, the ideas are able to extend to applications of other thin film photovoltaics and semiconductor devices.

Reproducible Ultrahigh SERS Enhancement in Single Deterministic Hotspots Using Nanosphere-Plane Antennas Under Radially Polarized Excitation.

Surface enhanced Raman scattering (SERS) in a nanometer size hotspot has empowered the investigation of chemical structures and dynamic behaviors of one and a few molecules. However, further advancement is hindered by lack of large enough yet reproducible enhancement in single deterministic hotspots. To resolve this problem, here we introduce a nanosphere-plane antenna under radially polarized laser excitation experiment, which provides an electromagnetic enhancement of 10(9~10) at the gap of each individual nanosphere-plane antenna and a root-mean-square error down to 10(0.08) between them. The experiment also reveals a nonlinear SERS behavior with less than one plasmon, which is also observed within a single hotspot. The unprecedented simultaneous achievement of ultrahigh enhancement and reproducibility in deterministic individual hotspots is attributed to the combination of a well-controlled hotspot geometry, the efficient coupling between vertical antenna and laser which produces orders of magnitude higher enhancement than previous excitation methods, and low power operation which is critical for high reproducibility. Our method opens a path for systematic studies on single and few molecule SERS and their surface chemistry in an in-situ and well-controlled manner.