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41.
A New Design Paradigm for Smart Windows: Photocurable Polymers for Quasi‐Solid Photoelectrochromic Devices with Excellent Long‐Term Stability under Real Outdoor Operating Conditions 下载免费PDF全文
Federico Bella George Leftheriotis Gianmarco Griffini George Syrrokostas Stefano Turri Michael Grätzel Claudio Gerbaldi 《Advanced functional materials》2016,26(7):1127-1137
A new photoelectrochromic device (PECD) is presented in this work proposing the combination of a WO3‐based electrochromic device (ECD) and a polymer‐based dye‐sensitized solar cell (DSSC). In the newly designed architecture, a photocurable polymeric membrane is employed as quasi‐solid electrolyte for both the ECD and the DSSC. In addition, a photocurable fluoropolymeric system is incorporated as solution‐processable external protective thin coating film with easy‐cleaning and UV‐shielding functionalities. Such new polymer‐based device assembly is characterized by excellent device operation with improved photocoloration efficiency and switching ability compared with analogous PECDs based on standard liquid electrolyte systems. In addition, long‐term (>2100 h) stability tests under continuous exposure to real outdoor conditions reveal the remarkable performance stability of this new quasi‐solid PECD system, attributed to the protective action of the photocurable fluorinated coating that effectively prevents photochemical and physical degradation of the PECD components during operation. This first example of quasi‐solid PECD systems paves the way for a new generation of thermally, electrochemically, and photochemically stable polymer‐based PECDs, and provides for the first time a clear demonstration of their true potential as readily upscalable smart window components for energy‐saving buildings. 相似文献
42.
Olivier Klein Steve Donovan Martin Dressel George Grüner 《Journal of Infrared, Millimeter and Terahertz Waves》1993,14(12):2423-2457
This report reviews the analysis used to extract the complex conductivity of a compound from a microwave cavity perturbation measurement. We intend to present a generalized treatment valid for any spheroidally shaped sample of arbitrary conductivity which is placed at either the electric or magnetic field antinode of the cavity. To begin with, we establish the relationship between the measured parameters and the conductivity for a spherical sample. Next, we extend these results to the case of spheroids; and for the first time, we cover all different configurations that one can possibly use to study an arbitrary conducting sample inside a cavity: in particular, all possible orientations of the sample with respect to the applied field are solved. 相似文献
43.
Supported palladium-silver oxides were used as catalysts for the partial oxidation of methane by molecular oxygen in a tubular reactor with ceramic wall separation. The ceramic wall controls the O2 supply in the catalyst bed. The results indicate that the reactor configuration can play an important role in methane oxidation. C2H6, C2H4, CO2 and H2O were obtained at temperatures less than 300 °C. At this temperature any contribution from homogeneous gas phase reaction can be ruled out. 相似文献
44.
AM Ghandour 《Canadian Metallurgical Quarterly》1976,50(3):193-196
An unusual form of left ventricular aneurysm affecting young Negroes has recently been described at the aortic or mitral valve ring; constitutional factors have been postulated. A 4-year-old Negro boy was observed with a left ventricular submitral aneurysm, probably one of the largest and one of the most calcified to be reported. Tuberculous lymphadenitis involving some of the mediastinal lymph nodes was found on postmortem examination; tuberculosis was believed to be a secondary contributing factor. A review of the literature disclosed only 5 other children with calcified left ventricular aneurysms, of which 2 were of the subvalvular type. 相似文献
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Serum IgE concentrations of patients with paragonimiasis were determined by a radioimmunosorbent test. The mean concentration was 3,462.3 IU/ml in a group of 13 cases of paragonimiasis miyazakii in which patients showed clinical symptoms and/or positive immunological diagnostic tests, and 1,026.6 IU/ml in a control group of 13 individuals who had eaten uncooked freshwater crabs, Potamon dehaani, but had been found to be free from the infection. Moreover, the IgE level of the pleural exudates obtained from four patients with paragonimiasis miyazakii on the day of bleeding or within several days after was significantly higher than that of their sera, ranging between 4,200 IU/ml and 10,000 IU/ml. This was true also in a case of paragonimiasis westermani. Sera and pleural exudates of patients with both forms of paragonimiasis were applied to immunosorbent columns of Sepharose 4B beads coupled with saline extracts of Paragonimus miyazakii, P. weetermani, or P. ohirai. IgE eluted from the corresponding column was considered to be specific, being around 5% to 10% of the total IgE. 相似文献
47.
Long-term low-dosage prophylaxis may be used in children with recurrent urinary tract infection to prevent reinfection of the urinary tract while the underlying cause of infection persists. Co-trimoxazole in a dose of 2 mg trimethoprin combined with 10 mg sulphamethoxazole per kg body weight daily has proved very effective: only six of 130 children receiving this treatment during a total period of 2637 months developed a reinfection. Co-trimoxazole was acceptable, compliance was good, and there were no important adverse effects. Supportive measures during prophylaxis are important. Sixty-five children were follow up after completion of their co-trimoxazole prophylaxis. Twenty-seven developed reinfections with fresh organisms, over two-thirds occurring within three months of discontinuing prophylaxis. Each one of these reinfections was sensitive to trimethoprin. The rectal flora were similarly sensitive. 相似文献
48.
In order to evaluate the preventive value of specific immune serum globulin against hepatitis type B, we have used this immune globulin in required doses in 12 patients (10 with AU antigen negative and 2 with AU antigen positive) with chronic renal failure who required maintenance hemodialysis for a period of 15 months, and we were able to prevent hepatitis type B in our dialysis patients. 相似文献
49.
50.
We report here an experience with five patients, aged 58 to 70, suffering gangrene of the left colon after spontaneous inferior mesenteric artery occlusion. All cases were the result of arteriosclerosis; in two, small aortic aneurysms were present and might have been responsible for emboli to the inferior mesenteric artery. The dead bowel was resected in all patients; three patients survived. No primary anastomoses were done and they are not recommended. Because ligation of the patent inferior mesenteric artery has been done so often without ill effects during aortic surgery, the collateral circulation to the left colon can be considered excellent. Gangrene is therefore rare and requires major interference with collateral circulation by emboli or arteriosclerotic occlusion. The clinical symptoms and signs may be confusing. 相似文献