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101.
A new series of charge neutral Os(II) isoquinolyl triazolate complexes ( 1 – 4 ) with both trans and cis arrangement of phosphine donors are synthesized, and their structural, electrochemical and photophysical properties are established. In sharp contrast to the cis‐arranged complexes 2 – 4 , the trans derivative 1 , which shows a planar arrangement of chromophoric N‐substituted chelates, offers the most effective extended π‐delocalization and hence the lowest excited state energy gap. These complexes exhibit phosphorescence with peak wavelengths ranging from 692–805 nm in degassed CH2Cl2 at room temperature. Near‐infrared (NIR)‐emitting electroluminescent devices employing 6 wt % of 1 (or 4 ) doped in Alq3 host material are successfully fabricated. The devices incorporating 1 as NIR phosphor exhibit fairly intense emission with a peak wavelength at 814 nm. Forward radiant emittance reaches as high as 65.02 µW cm?2, and a peak EQE of ~1.5% with devices employing Alq3, TPBi and/or TAZ as electron‐transporting/exciton‐blocking layers. Upon switching to phosphor 4 , the electroluminescence blue shifts to 718 nm, while the maximum EQE and radiance increase to 2.7% and 93.26 (μW cm?2) respectively. Their performances are optimized upon using TAZ as the electron transporting and exciton‐blocking material. The OLEDs characterized represent the only NIR‐emitting devices fabricated using charge‐neutral and volatile Os(II) phosphors via thermal vacuum deposition.  相似文献   
102.
Chang YF  Hung SH  Lee YJ  Chen RC  Su LC  Lai CS  Chou C 《Analytical chemistry》2011,83(13):5324-5328
Prostate-specific antigen (PSA) has been reported to be a potential biomarker of breast cancer. Serum PSA of normal women is around 1 pg/mL, which is usually undetectable by current assay methods; thus an ultrasensitive measurement of PSA expression in women's serum is necessary to distinguish normal from malignant breast diseases. To enhance the sensitivity of conventional immunoassay technology for the detection of PSA in sera, we adopted a localized surface plasmon coupled fluorescence fiber-optic biosensor, which combines a sandwich immunoassay with the localized surface plasmon technique. The concentration of total PSA (t-PSA) (from 0.1 to 1000 pg/mL) in phosphate-buffered saline solution and the normalized fluorescence signal exhibit a linear relationship where the correlation coefficient is 0.9574. In addition, the concentration of additional t-PSA in 10-fold-diluted healthly women's serum across a similar range was measured. The correlation coefficient for this measurement is 0.9142. In clinical serum samples, moreover, the experimental results of t-PSA detection show that both the mean value and median of normalized fluorescence signals in the breast cancer group (155.2 and 145.7, respectively) are higher than those in the noncancer group (46.6 and 37.1, respectively). We also examined the receiver operating characteristic curve for t-PSA, and the area under the curve (AUC) is estimated to be 0.9063, the AUC being used to measure the performance of a test to correctly identify diseased and nondiseased subjects.  相似文献   
103.
104.
Perovskite solar cells (PSCs) have emerged as one of the most promising and competitive photovoltaic technologies, and doctor-blading is a facile and robust deposition technique to efficiently fabricate PSCs in large scale, especially matching with roll-to-roll process. Herein, it demonstrates the encouraging results of one-step, antisolvent-free doctor-bladed methylammonium lead iodide (CH3NH3PbI3, MAPbI3) PSCs under a wide range of humidity from 45% to 82%. A synergy strategy of ionic-liquid methylammonium acetate (MAAc) and molecular phenylurea additives is developed to modulate the morphology and crystallization process of MAPbI3 perovskite film, leading to high-quality MAPbI3 perovskite film with large-size crystal, low defect density, and ultrasmooth surface. Impressive power conversion efficiency (PCE) of 20.34% is achieved for doctor-bladed PSCs under the humidity over 80% with a device structure of ITO/SnO2/MAPbI3/Spiro-OMeTAD/Ag. It is the highest PCEs for one-step solution-processed MAPbI3 PSCs without antisolvent assistance. The research provides a facile and robust large-scale deposition technique to fabricate highly efficient and stable PSCs under a wide range of humidity, even with the humidity over 80%.  相似文献   
105.
The purpose of this study is to evaluate the physicochemical properties and in vitro osteogenic activity of radiopaque calcium silicate–gelatin cements. The radiopacity, setting time, working time, flow, diametral tensile strength, pH value, washout resistance and morphology of the cements with gelatin (0, 5 and 10 % by weight) were measured, which compared to a popular endodontic material, ProRoot white-colored mineral trioxide aggregate (WMTA). The cell morphology, cell attachment and proliferation, alkaline phosphatase and osteocalcin levels on the cements were measured by culturing the specimens with dental pulp cells. The results indicated that the presence of gelatin significantly (P < 0.05) reduced radiopacity and diametral tensile strength and prolonged setting time. Nevertheless, the 5 wt% gelatin cement had a radiopacity (5.1 mm of Al thickness) higher than ISO 6876:2001 standards (3 mm of Al thickness). The setting time (33 min), working time (9 min) and flow value (17.4 mm) of the 5 wt% gelatin cement were significantly (P < 0.05) better than those of WMTA (corresponding 165, 6 min and 14.2 mm). The fresh WMTA completely degraded after soaking in a physiological solution for 1 h, while the gelatin cements resisted washout, showing no noticeable breakdown even after 1 day of soaking. The gelatin cement enhanced the higher expression of cell attachment, proliferation and differentiation as compared to WMTA. It was concluded that the 5 wt% gelatin–calcium silicate hybrid cement appears to be promising as a radiopaque biomaterial for medical applications such as endodontics and vertebroplasty.  相似文献   
106.
This article presents a four-port adjustable inductor with 0.18?µm Complementary Metal-Oxide-Semiconductor (CMOS) technology on plastic. The inductor has a high Q-factor and a small size for multiband UWB applications. When the four-port adjustable inductor, on VLSI-standard Si substrate, operates near 3, 4, 7.5 and 9?GHz, it has a Q-factor of 6.5, 6.7, 8 and 11.5 and an inductance of 2.1, 1.6, 1.1, 0.6?nH, respectively. Reducing the thickness of the Si substrate to 90?µm and mounting it on plastic causes a 25–31% improvement in the Q-factor, without change in the inductance, due to a reduction in the parasitic effect from the Si substrate. This is useful for multiband applications.  相似文献   
107.
We demonstrated an all-solution-processed electron selective layer, active layer and top electrode for large-area inverted organic solar cells. The fabricated devices are semitransparent, fully spray-coated, highly efficient and air-stable, with power efficiencies of 2.41% and 1.0% for cell areas of 0.36 and 15.25 cm2, respectively. The shelf life of the cells in air is demonstrated by the ∼80% retention of original cell efficiency after 30 days.  相似文献   
108.
本文采用在ITU-TG.805建议中定义的传送网通用功能结构模型,建立了PDH传送网功能结构模型;在这一达网功能结构模型的基础上,结合PDH光传输系统的网管要求,建立了网元观点的PDH光传输系统信息模型。  相似文献   
109.
武汉市涉核单位众多,存在一定的核与辐射事故风险。通过对武汉市举办第七届世界军人运动会可能存在的核与辐射风险因素进行识别及评价,确定可能发生的12类核与辐射事故类型及风险水平,进而有针对性的制定风险防控措施,做到辐射应急管理关口前移,在保证军运会期间核技术利用单位正常生产活动的基础上有效的保障了核与辐射安全。  相似文献   
110.
A group of five plant inherent control tests was successfully conducted in November 1987 in the Experimental Breeder Reactor II. These tests demonstrated that the plant power of a metal-fueled reactor can be passively controlled over a large power range by slowly changing the primary flow and the reactor inlet temperature. These variables are, in turn, regulated by the primary pump speed, the secondary flow, and the turbine inlet pressure. In all tests, control rods were not used to regulate power. It was demonstrated that the plant power can be controlled with reasonable accuracy without using control rods when the reactivity feedback characteristics of the reactor are well understood and the plant controllers are adequately designed.  相似文献   
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