Forty two major (Na, Mg, Ti and Mn) and trace elements covering the mass range from Li to U in three USGS basalt glass reference materials BCR‐2G, BHVO‐2G and BIR‐1G were determined using laser ablation‐inductively coupled plasma‐mass spectrometry. Calibration was performed using NIST SRM 610 in conjunction with internal standardisation using Ca. Determinations were also made on NIST SRM 612 and 614 as well as NIST SRM 610 as unknown samples, and included forty five major (Al and Na) and trace elements. Relative standard deviation (RSD) of determinations was below 10% for most elements in all the glasses under investigation. Consistent exceptions were Sn and Sb in BCR‐2G, BHVO‐2G and BIR‐1G. For BCR‐2G, BHVO‐2G and BIR‐1G, clear negative correlations on a logarithmic scale exist between RSD and concentration for elements lower than 1500 μg g‐1 with logarithmic correlation coefficients between ‐0.75 and ‐0.86. There is also a clear trend of increasing RSD with decreasing concentration from NIST SRM 610 through SRM 612 to SRM 614. These suggest that the difference in the scatter of apparent element concentrations is not due to chemical heterogeneity but reflects analytical uncertainty. It is concluded that all these glasses are, overall, homogeneous on a scale of 60 μm. Our first results on BHVO‐2G and BIR‐1G showed that they generally agreed with BHVO‐2/BHVO‐1 and BIR‐1 within 10% relative. Exceptions were Nb, Ta and Pb in BHVO‐2G, which were 14‐45% lower than reference values for BHVO‐2 and BHVO‐1. Be, Ni, Zn, Y, Zr, Nb, Sn, Sb, Gd, Tb, Er, Pb and U in BIR‐1G were also exceptions. However, of these elements, Be, Nb, Sn, Sb, Gd, Tb, Pb and U gave results that were consistent within an uncertainty of 2s between our data and BIR‐1 reference values. Results on NIST SRM 612 agreed well with published data, except for Mg and Sn. This was also true for elements with m/z 85 (Rb) in the case of NIST SRM 614. The good agreement between measured and reference values for Na and Mg in BCR‐2G, BHVO‐2G and BIR‐1G, and for Al and Na in NIST SRM 610, 612 and 614 up to concentrations of at least several weight percent (which were possible to analyse due to the dynamic range of 108) indicates the suitability of this technique for major, minor and trace element determinations.

A set of biocompatible, biodegradable, and biofunctionalizable diffractive optical elements (DOEs) using silk proteins as the building materials is reported. The diffraction pattern of a DOE is highly sensitive to the surrounding environment and the structural integrity, offering numerous opportunities for biosensing applications.

Controllable degradation and excellent biocompatibility during/after a lifetime endow emerging transient electronics with special superiority in implantable biomedical applications. Currently, most of these devices need external power sources, limiting their real-world utilizations. Optimizing existing bioresorbable electronic devices requires natural-material-based construction and, more importantly, diverse or even all-in-one multifunctionalization. Herein, silk-based implantable, biodegradable, and multifunctional systems, self-powered with transient triboelectric nanogenerators (T ENGs), for real-time in vivo monitoring and therapeutic treatments of epileptic seizures, are reported. These T ENGs are of customizable in vitro/in vivo operating life and biomechanical sensitivity via the adjustments of silk molecular size, surface structuralization, and device configuration. Functions, such as drug delivery and structural-integrity optical readout (parallel to electronic signals), are enabled for localized anti-infection and noninvasive degradation indication, respectively. A proof-of-principle wireless system is built with mobile-device readout and "smart" treatment triggered by specific symptoms (i.e., epilepsy), exhibiting the practical potential of these silk T ENGs as self-powered, transient, and multifunctional implantable bioelectronic platforms.

The atmospheric chemistry of CF3OCH3, a possible HCFCs/HFCs substitute was studied using a smog chamber/FTIR technique. The ether was reacted with OH radicals prepared by photolysis of ozone in 100 Torr of an H2O/O2/He gas mixture in a 1 m3 temperature-controlled chamber. Using a relative rate method, k(OH + CF3OCH3) = (4.22 ± 0.84) × 10-12 exp[(−1750 ± 350)/T] cm3 molecule-1 s-1 over the temperature range 268−308 K. The rate constant at 298 K was (1.19 ± 0.14) × 10-14 cm3 molecule-1 s-1. The products of the OH radical initiated degradation of CF3OCH3 were investigated in 100−230 Torr of an O2/He gas mixture at 298 K using in situ FTIR spectroscopy. k(OH + CF3OC(O)H) = (1.68 ± 0.20) × 10-14 cm3 molecule-1 s-1 at 298 K was determined. The major products of the oxidation of CF3OC(O)H were COF2 and CO2. These results are discussed with respect to the atmospheric chemistry of CF3OCH3 and CF3OC(O)H.

We have developed a technique for generating high concentrations of gaseous OH radicals in a reaction chamber. The technique, which involves the UV photolysis of O 3 in the presence of water vapor, was used in combination with the relative rate method to obtain rate constants for reactions of OH radicals with selected species. A key improvement of the technique is that an O 3 /O 2 (3%) gas mixture is continuously introduced into the reaction chamber, during the UV irradiation period. An important feature is that a high concentration of OH radicals [(0.53-1.2) × 10 11 radicals cm −3 ] can be produced during the irradiation in continuous, steady-state experiment. Using the new technique in conjunction with the relative rate method, we obtained the rate constant for the reaction of CHF 3 (HFC-23) with OH radicals, k 1 . We obtained k 1 (298 K) = (3.32 ± 0.20) × 10 −16 and determined the temperature dependence of k 1 to be (0.48 ± 0.13) × 10 −12 exp[−(2180 ± 100)/T] cm 3 molecule −1 s −1 at 253-328 K using CHF 2 CF 3 (HFC-125) and CHF 2 Cl (HCFC-22) as reference compounds in CHF 3 -reference-H 2 O gas mixtures. The value of k 1 obtained in this study is in agreement with previous measurements of k 1 . This result confirms that our technique for generating OH radicals is suitable for obtaining OH radical reaction rate constants of ∼10 −16 cm 3 molecule −1 s −1 , provided the rate constants do not depend on pressure. In addition, it also needed to examine whether the reactions of sample and reference compound with O 3 interfere the measurement when selecting this technique. C

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