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Because of their excellent properties, metal-organic frameworks (MOFs) are considered as ideal materials for the development of visible-light photocatalyst. Particularly, although increasing research interests have been put on MOF based photocatalysts, the MOF supported Ag2CO3 as photocatalyst has not been reported in the field of water treatment. In this study, a zirconium based MOF, UiO-66, was incorporated with Ag2CO3 through a convenient solution method and used for visible-light prompted dye degradation. Compared to the mixture of pristine UiO-66 and Ag2CO3, the developed Ag2CO3/UiO-66 composite exhibited enhanced photocatalytic activity to the degradation of rhodamine B (RhB) under visible-light irradiation. It was supposed that the participation of UiO-66 during the synthesis of Ag2CO3 was crucial for such improvement. In addition, the Ag2CO3/UiO-66 composite demonstrated good structural stability after the degradation experiment, and most of its photocatalytic activity was still preserved after the recycle test. Moreover, the photocatalytic mechanism of the Ag2CO3/UiO-66 composite was investigated and a possible pathway of RhB degradation was also proposed.

— UAV (Unmanned Aerial Vehicle) is a term used to represent flying objects with their own power supply that can be controlled remotely using remote control from outside the aircraft or can move automatically based on programs already embedded in the computer system. This system used manual and autopilot controls. In manual mode the user manually controls the movement of the aircraft through the radio controller while in the airplane autopilot mode controlled by microcontroller Ardupilot Mega 2.8 that processes the data sensor IMU (Inertial Measurement Unit) in which there are gyroscope and accelerometer, GPS and barometric altimeter so that it can fly in automatically with corresponding waypoint GPS entered. The form of the UAV is very light, small, and only made of styrofoam so as to make the UAV vulnerable to wind and rain disturbances that often cause the plane when in the air becomes unstable. In this final project, be designed UAV with fixed wing type. The design of this UAV control system uses ardupilot control with mission planner application, with the aim of controlling and designing the flight path on the plane so that the aircraft can fly in Autopilot Mode (automatic mode) that can be manually activated from the Fs-i6 remote control. Keywords — Autopilot, Fixed wing, Unmanned Aerial Vehicle, waypoint Abstrak — UAV (Unmanned Aerial Vehicle) merupakan istilah yang digunakan untuk mereprentasikan benda terbang dengan suplay daya sendiri yang bisa dikendalikan dari jarak jauh menggunakan remote control dari luar pesawat atau dapat bergerak secara otomatis berdasarkan program yang sudah ditanamkan pada sistem komputernya. Sistem ini menggunakan kontrol manual dan autopilot, Pada mode manual pengguna secara manual mengendalikan pergerakan pesawat melalui radio kontroler sedangkan pada mode autopilot pesawat dikendalikan oleh mikrokontroler Ardupilot Mega 2.8 yang mengolah data-data sensor IMU (Inertial Measurement Unit) yang didalamnya terdapat gyroscope dan accelerometer, GPS dan barometric altimeter sehingga dapat terbang secara otomatis dengan sesuai waypoint GPS yang dimasukkan. Bentuk dari UAV pun sangat ringan, kecil, dan hanya terbuat dari styrofoam sehingga membuat UAV rentan terhadap gangguan angin maupun hujan yang sering menyebabkan pesawat saat di udara menjadi tidak stabil. Pada tugas akhir ini, dirancang UAV dengan tipe fixed wing. Perancangan sistem kontrol UAV ini menggunakan kontrol ardupilot dengan aplikasi mission planner, dengan tujuan mengontrol dan merancang jalur penerbangan pada pesawat sehingga pesawat tersebut dapat terbang dengan Mode Autopilot (mode otomatis) diaktifkan secara manual dari remote control Fs-i6. Kata kunci — Autopilot, Fixed wing, Unmanned Aerial Vehicle, waypoint

Visible-light photocatalysts that degrade organic pollutants in an efficient and recyclable way are highly desirable for water treatment. In this study, UiO-66, a zirconium-based metal-organic framework, was conjugated with AgI to obtain a composite for use as photocatalyst. The AgI/UiO-66 composites with different composition ratios were synthesized by a simple solution method and exhibited remarkable activity for the degradation of rhodamine B (RhB) under visible-light irradiation. The scanning electron microscopy and X-ray diffraction results confirmed the outstanding structural stability of the AgI/UiO-66 photocatalysts. The photocatalytic stability of the AgI/UiO-66 composite was further examined by reusing AgI/UiO-66 for long-term dye degradation. The good stability of the AgI/UiO-66 composite can be attributed to the outstanding stability of the UiO-66 framework material, as well as the good interaction between AgI and the UiO-66 framework. The mechanism of the photocatalytic RhB degradation by AgI/UiO-66 was investigated by introducing different scavengers to compete for the possible reactive species involved in the degradation process.

Major river flooding affected the United Kingdom in late September 2012 as a slow-moving extratropical cyclone brought over 150 mm of rain to parts of northern England and north Wales. The cyclone deepened over the United Kingdom on 24–26 September as a potential vorticity (PV) anomaly approached from the northwest, elongated into a PV streamer, and wrapped around the cyclone. The strength and position of the PV anomaly is modified in the initial conditions of Weather Research and Forecasting Model simulations, using PV surgery, to examine whether different upper-level forcing, or different phasing between the PV anomaly and cyclone, could have produced an even more extreme event. These simulations reveal that quasigeostrophic (QG) forcing for ascent ahead of the anomaly contributed to the persistence of the rainfall over the United Kingdom. Moreover, weakening the anomaly resulted in lower rainfall accumulations across the United Kingdom, suggesting that the impact of the event might be proportional to the strength of the upper-level QG forcing. However, when the anomaly was strengthened, it rotated cyclonically around a large-scale trough over Iceland rather than moving eastward as in the verifying analysis, with strongly reduced accumulated rainfall across the United Kingdom. A similar evolution developed when the anomaly was moved farther away from the cyclone. Conversely, moving the anomaly nearer to the cyclone produced a similar solution to the verifying analysis, with slightly increased rainfall totals. These counterintuitive results suggest that the verifying analysis represented almost the highest-impact scenario possible for this flooding event when accounting for sensitivity to the initial position and strength of the PV anomaly.

Major river flooding affected the United Kingdom in late September 2012 as a slow-moving extratropical cyclone brought over 100 mm of rain to a large swath of northern England and north Wales, with local accumulations approaching 200 mm. The cyclone developed on 20–22 September following the interaction between an equatorward-moving potential vorticity (PV) streamer and Tropical Storm Nadine, near the Azores. A plume of tropical moisture was drawn poleward ahead of the PV streamer over a low-level baroclinic zone, allowing deep convection to develop. Convectively driven latent heat release reduced upper-tropospheric PV near the streamer, causing it to fracture and cut off from the reservoir of high PV over the United Kingdom. Simulations using the Weather Research and Forecasting Model with 4-km horizontal grid spacing in which microphysical heating and cooling tendencies are set to zero, alongside calculations of instantaneous diabatic heating rates and PV tendencies along trajectories, reveal that deposition heating contributed strongly to the fracturing of the PV streamer into a discrete anomaly by directly reducing upper-tropospheric PV to the streamer’s east. Condensation heating contributed to lower-tropospheric PV generation along the cold front as the cyclone developed, while cooling due to sublimation, evaporation, and melting modified the PV much less strongly. The results of this case study show that the collocation of strong deposition heating with positive absolute vorticity in the upper troposphere can lead to substantial PV modification and a very different cyclone evolution to that when deposition heating is suppressed.

Borexino is a large-volume liquid scintillator detector placed in the underground halls of the Laboratori Nazionali del Gran Sasso in Italy. After several years of construction, data taking started in May 2007, providing immediately incontrovertible evidence of the unprecedented radiopurity of the target mass. Here we report on the newest Borexino results obtained with about 200 days of data. Borexino provides the first direct measurement of the solar neutrino survival probability in both vacuum-dominated and matter-enhanced regions provided by a single experiment. The interaction rate of the 0.862 MeV 7 Be solar neutrinos is found to be 49 ± 3 stat ± 4 sys counts/(day⋅100 tons), in agreement with the oscillation hypothesis in the MSW Large Mixing Angle scenario. The first real-time measurement of the 8 B solar neutrinos above 2.8 MeV provides interaction rate of 0.26 ± 0.04 stat ± 0.02 sys counts/(day⋅100 tons). These measurements improve the experimental determination of the flux of the pp and CNO solar neutrinos, and the limit on the effective magnetic moment using solar neutrinos.

Metal–organic frameworks (MOFs) have many outstanding properties that make them candidate materials for the development of high performance catalysts. Visible-light promoted photocatalysis for the degradation of organic pollutants is a promising direction in the field of water treatment. However, studies applying MOFs as photocatalyst for water treatment are very limited. In this study, UiO-66, a zirconium based MOF, was incorporated with bismuth tungstate (Bi2WO6) by a simple hydrothermal method for the development of visible-light photocatalysts. The Bi2WO6/UiO-66 composite not only exhibited enhanced photocatalytic activity for the degradation of Rhodamine B (RhB) under visible-light irradiation, but also showed good catalyst stability. In the recycled dye degradation experiments, most activity of the composite was reserved, and the structure and morphology of the composite did not vary after the experiment of dye degradation, either. The photocatalytic activity of Bi2WO6/UiO-66 composites with varying Bi : Zr molar ratios were investigated and the optimum Bi2WO6 content was found. Also, by introducing different scavengers to compete for the active species involved in the degradation process, the mechanism of the photocatalytic degradation of RhB by the Bi2WO6/UiO-66 composite was studied.

We report a new concept of using conjugated polyfluorene imidazolium ionic liquids (PILs) intercalated reduced graphene oxide for high performance supercapacitor electrode materials. Two polyfluorene homo-polymer (hoPIL) and co-polymer (co-PIL) carrying hexyl imidazolium bromide side chains were designed and synthesized. Their corresponding intercalated reduced graphene oxide materials hoPIL-RGO and coPIL-RGO exhibited good electrochemical performance in aqueous electrolytes as well as in ionic liquid electrolyte 1-butyl-3-methylimidazolium tetrafluoroborate (BMIMBF4). High specific capacitances of 222 F g−1 at a current density of 0.2 A g−1 and 132 F g−1 at 0.5 A g−1 were obtained for coPIL-RGO in 6 M KOH and BMIMBF4 accordingly. When assembled into a symmetric two-electrode cell with graphene materials as electrodes and BMIMBF4/acetonitrile (1:1) as electrolyte, an energy density of 14.7 Wh kg−1 was obtained for coPIL-RGO at a current density of 0.5 A g−1, and a maximum power density of 347 kW kg−1 was achieved for hoPIL-RGO at a current density of 5 A g−1 with good cycling stability.

The syntheses of conjugated polymers poly(2,6-(dithieno[3,2-b:2′,3′-d]thiophenyl)-alt-2,5-(3,4-dialkoxy)thiophenyl) were achieved by reacting 2,6-dibromodithieno[3,2-b:2′,3′-d]thiophene with respective 2,5-bis(trimethyltin)-3,4-dialkoxythiophene in medium yields via a Stille coupling reaction. The resulting polymers are highly soluble in some common organic solvents. The polymer films are purple at neutral states and gradually become gray upon progressive oxidation by applying an external potential as a result of absorption across the whole visible spectrum. At the fully oxidized state, the polymers become transmissive light blue. In particular, polymer poly(2,6-(dithieno[3,2-b:2′,3′-d]thiophenyl)-alt-2,5-(3,4-didecyloxy)thiophenyl) (P1) film exhibits exceptional high optical contrasts of 46% and 72% in the visible and near-infrared regions, respectively, with good stability over 800 full cycles. An absorptive-transmissive electrochromic device (ECD) of P1 exhibits a contrast ratio of 15% at λmax of 534 nm and 20% at 1321 nm and high coloration efficiency of 449 and 471 cm2/C, respectively. This type of multichromic polymers would thus be promising materials for electrochromic displays and inks.

Background: The purpose of this study was to determine the cerebrovascular risk stratification potential of baseline degree of stenosis, clinical features, and ultrasonic plaque characteristics in patients with asymptomatic internal carotid artery (ICA) stenosis. Methods: This was a prospective, multicenter, cohort study of patients undergoing medical intervention for vascular disease. Hazard ratios for ICA stenosis, clinical features, and plaque texture features associated with ipsilateral cerebrovascular or retinal ischemic (CORI) events were calculated using proportional hazards models. Results: A total of 1121 patients with 50% to 99% asymptomatic ICA stenosis in relation to the bulb (European Carotid Surgery Trial [ECST] method) were followed-up for 6 to 96 months (mean, 48). A total of 130 ipsilateral CORI events occurred. Severity of stenosis, age, systolic blood pressure, increased serum creatinine, smoking history of more than 10 pack-years, history of contralateral transient ischemic attacks (TIAs) or stroke, low grayscale median (GSM), increased plaque area, plaque types 1, 2, and 3, and the presence of discrete white areas (DWAs) without acoustic shadowing were associated with increased risk. Receiver operating characteristic (ROC) curves were constructed for predicted risk versus observed CORI events as a measure of model validity. The areas under the ROC curves for a model of stenosis alone, a model of stenosis combined with clinical features and a model of stenosis combined with clinical, and plaque features were 0.59 (95% confidence interval [CI] 0.54-0.64), 0.66 (0.62-0.72), and 0.82 (0.78-0.86), respectively. In the last model, stenosis, history of contralateral TIAs or stroke, GSM, plaque area, and DWAs were independent predictors of ipsilateral CORI events. Combinations of these could stratify patients into different levels of risk for ipsilateral CORI and stroke, with predicted risk close to observed risk. Of the 923 patients with