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To mitigate the decrease in mechanical performance of Sn58Bi/Cu solder joints resulting from electromigration-induced damage. The CeO2 nanoparticles were incorporated into Sn58Bi solder by a melt-casting method, and their effects on the microstructure and properties of Sn58Bi/Cu solder joints under electromigration were investigated. The study results demonstrate that the addition of 0.125 ~ 0.5 wt% CeO2 nanoparticles refines the eutectic microstructure of Sn58Bi solder alloy. At an addition amount of 0.5 wt%, the composite solder alloy exhibits the maximum tensile strength of 68.9 MPa, which is 37% higher than that of the base solder. CeO2 nanoparticle-reinforced Sn58Bi solder can achieve excellent solderbility with Cu substrates and the joints can significantly inhibit the growth of the anodic Bi-rich layer, which is responsible for electromigration. With the extension of current stressing time, Bi-rich and Sn-rich layer are respectively formed on the anode and cathode in the joints. The intermetallic compound (IMC) layer grows asymmetrically, transitioning from a fan-shaped morphology to a flattened structure at the anode and to a thickened mountain-like morphology at the cathode. Adding the CeO2 nanoparticles helps to mitigate the decrease in mechanical performance caused by electromigration damage during current application to some extent. Over the current stressing period of 288 ~ 480 h, the fracture position shifts from the anodic IMC/Bi-rich interface to the cathodic Sn-rich/IMC interface. The fracture mechanism transitions from a brittle fracture characterized by plate-like cleavage to a ductile–brittle mixed fracture with fine dimples and cleavage. [ABSTRACT FROM AUTHOR]

As a non-invasive body fluid, urine pH is one of the important biomarkers for diseases such as the kidneys. Therefore, rapid and accurate detection of urine pH is of great clinical significance. A novel fluorescent probe (SPPH-Cl) was developed based on Brooker’s merocyanine skeleton for pH detection. The pKa of SPPH-Cl was adjusted to 6.55 using a phenolic hydroxyl ortho substitution strategy, therefore, the fluorescence response range of SPPH-Cl to pH covers the urine physiological pH range (4.6-8.0). SPPH-Cl has excellent water solubility, stable recoverability, wide anti-interference capability, and sensitive reactions to pH fluctuations in pure aqueous solutions. SPPH-Cl has succeeded in applying to monitor the pH of volunteer urine samples based on a standard curve established in artificially simulated urine, and the detection results have accuracy comparable to pH meters. Therefore, this work provided a powerful molecule tool for detecting pH in urine samples. [ABSTRACT FROM AUTHOR]

Tunnel Boring Machines (TBMs) have been used in many underground coal mines in China with high constructive efficiency, sound equipment integration and low cost. A recent application of TBM in Yuandian No.2 Coal Mine in Huaibei, China, has shown that the surrounding rockmass spalled severely in stratum impacted by multiple joint sets. To analyze this problem, a new 3D ubiquitous-multiple-joint (UMJ) model was proposed in the present research, which comprised a rock matrix and multiple sets of joints according to geological conditions. Then, the yielding and deformation of the roadway excavated by TBM were analyzed. The results showed that the plastic zones, stress states and displacement of surrounding rockmass were significantly affected by the orientation of joint sets. The results could well indicate failure characteristics of the in-situ roadway and showed the advantages of UMJ model to simulate the excavation in jointed rockmass. The key factors influencing the roadway stability were discussed by the UMJ model. Based on the simulation results, suggestions on excavation-support schemes were proposed for TBM excavating roadways. Highlights: 3D Ubiquitous-Multiple-Joint model is proposed to handle rockmass with multiple joint sets The stability of roadway is significantly affected by orientation and strength of joint sets Some measures are suggested to control TBM excavated roadway in jointed stratum [ABSTRACT FROM AUTHOR]

Machine translation of chemical nomenclature has considerable application prospect in chemical text data processing between languages. However, rule based machine translation tools have to face significant complication in rule sets building, especially in translation of chemical names between English and Chinese, which are the two most used languages of chemical nomenclature in the world. We applied two types of neural networks in the task of chemical nomenclature translation between English and Chinese, and made a comparison with an existing rule based machine translation tool. The result shows that deep learning based approaches have a great chance to precede rule based translation tools in machine translation of chemical nomenclature between English and Chinese. [ABSTRACT FROM AUTHOR]

NAZ2329 is the first cell-permeable small molecular allosteric inhibitor of protein tyrosine phosphatase receptor–type Z (PTPRZ), which was considered as a new potential molecular target for drug development in glioblastoma. A facile and high-efficient synthesis of NAZ2329 was developed by a straight-forward strategy starting from key ethoxy benzyl bromide intermediate obtained from commercially available 4-(trifluoromethyl)phenol. [ABSTRACT FROM AUTHOR]

Low-bandgap conjugated polymers with photocurrent response to near-infrared (NIR) wavelength are the basis of optoelectronic technologies such as semitransparent organic photovoltaics (STOPVs), NIR polymer photodetectors (PPDs), ambipolar field-effect transistors (FETs), photoacoustic (PA) imaging and photothermal therapy (PTT). Compared with inorganic-based photodetectors, PPDs, based on low-bandgap conjugated polymers with the chemical structures easy to be tuned, can achieve a wide range of spectral responses. On the other hand, this kind of polymers can enhance the short-circuit current (JSC) in TOPV by extending the absorption spectrum range. In this review, our focus will be on the development of low-bandgap conjugated polymers extending over 1000 nm and the performance of PPDs or OPVs. The perspective article summarizes the design strategy of such polymers, the derivation process of the useful heterocycles, absorption, bandgap, and energy levels. Thereafter, we will draw attention to the challenges and the possible research direction in the future to provide readers with a deeper understanding of the design of NIR polymers. [ABSTRACT FROM AUTHOR]

Activated persulfates are efficient reagents for oxidation of organic contaminants and water treatment. Various compounds are currently used to activate persulfates, but there is a need for cheap and efficient activators. Here, we report the first use of steel slag, an industrial solid waste, as a solid activator for peroxydisulfate activation. We tested this system for bisphenol A degradation. Results indicate that about 70% of bisphenol A can be removed within 1 h. Conditions were 50 μg/L of bisphenol A, 2 g/L of peroxydisulfate, 3 g/L of steel slag and temperature of 298 K. The components and surface morphology of unused and recycled steel slag were analyzed by X-ray diffraction and scanning electron microscopy, whereas the main reactive oxygen species were elucidated by using radical scavengers. Findings show that both base oxides and iron oxides are responsible for peroxydisulfate activation. A redox mechanism involving liquid and solid phases is proposed. Overall, this study reveals the successful recycling of steel slag to activate persulfates for water treatment, following the principle of ‘waste control by waste.’ [ABSTRACT FROM AUTHOR]