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161.
Low-voltage antimony-doped SnO2 nanowire transparent transistors gated by microporous SiO2-based proton conductors 下载免费PDF全文
A battery drivable low-voltage transparent lightly antimony(Sb)-doped SnO2 nanowire electric-double-layer (EDL) field-effect transistor (FET) is fabricated on an ITO glass substrate at room temperature. An ultralow operation voltage of 1 V is obtained on account of an untralarge specific gate capacitance (- 2.14 μF/cm2) directly bound up with mobile ions-induced EDL (sandwiched between the top and bottom electrodes) effect. The transparent FET shows excellent electric characteristics with a field-effect mobility of 54.43 cm2/V. s, current on/off ration of 2 × 104, and subthreshold gate voltage swing (S = dVgs/d(logIds)) of 140 mV/decade. The threshold voltage Yth (0.1 V) is estimated which indicates that the SnO2 namowire transistor operates in an n-type enhanced mode. Such a low-voltage transparent nanowire transistor gated by a microporous SiO2-based solid electrolyte is very promising for battery-powered portable nanoscale sensors. 相似文献
162.
为提高电池的光电转换效率,通过改善激光刻蚀工艺,采用355 nm紫外纳秒激光分别进行了ZnO:Al薄膜(AZO)刻蚀(P1)、非晶硅薄膜(-Si)刻蚀(P2)和背电极刻蚀(P3)研究。采用万用表测量P1隔离电阻,采用电子扫描显微镜(SEM)和三维激光扫描仪测量刻槽的微结构和三维成像,激光拉曼散射光谱检测非晶硅薄膜刻蚀边缘的晶化。实验结果表明,当刻蚀速度600 mm/s,重复频率40 kHz,功率1.74 W的紫外激光刻蚀ZnO:Al薄膜时,刻槽的隔离效果最佳,达20 M; 紫外激光刻蚀能够有效地减小激光热效应引起的热影响和刻槽边缘的晶化范围,提高非晶硅薄膜电池的性能。 相似文献
163.
采用射频磁控溅射制备了非晶态结构的Hg1-xCdxTe薄膜,并利用台阶仪、XRD、原子力显微镜、EDS等分析手段对薄膜生长速率、物相、表面形貌、组分比例进行了研究。实验结果表明,溅射气压对薄膜生长速率、微观结构、表面形貌和化学组分有直接影响。随着溅射气压增大,其生长速率逐渐降低。当溅射气压高于1.1 Pa时,薄膜XRD图谱上没有出现任何特征衍射峰,只是在2θ=23°附近出现衍射波包,具有明显的非晶态特征;当溅射气压小于1.1 Pa时,XRD谱表现为多晶结构。另外,随着溅射气压的增加,薄膜表面粗糙度逐渐减小,而且溅射气压对薄膜组成的化学计量比有明显影响,当溅射气压为1.1 Pa时,薄膜中Hg的组分比最低,而Cd组分比最高。 相似文献
164.
A simple, sensitive and rapid ultra‐high‐performance liquid chromatography–electrospray ionization–tandem mass spectrometry method was developed and validated for the quantification of warfarin and 7‐hydroxy warfarin in Sprague Dawley (SD) rats. Animals were administered a single dose of warfarin sodium formulations (crystalline and amorphous) at 12 mg/kg via oral gavage and blood was drawn over a 96‐h time course. Sample process recoveries, matrix effect and analyte stability were determined. The linearity for warfarin and 7‐hydroxy warfarin was from 5 to 2000 ng/mL in blank SD rat plasma. Correlation coefficients (r2) for standard calibration curves were >.98 and analytes quantified within ±15% of target at all calibrator concentrations. The average percent accuracy and precision for intra‐ and inter‐day were 93.7%–113.8% and ≤12.1%, respectively, for warfarin and 7‐hydroxy warfarin, across the quality control standards (5, 10, 500, 1800 and 2000 ng/mL). Acceptable analytical recovery (>55%) was achieved with process efficiencies >41.5% and matrix effects <139.9% over the analytical range. Both analytes were stable in stock solution, autosampler, benchtop and three cycles of freeze–thaw with percent accuracy ≥90.2% and precision (percent relative standard deviation) ≤14%. The validated method was successfully applied to a pre‐clinical bioavailability study of crystalline and amorphous warfarin sodium formulations in SD rats. 相似文献
165.
过渡金属醋酸盐与邻菲咯啉的室温固相配位化学反应研究 总被引:1,自引:0,他引:1
本文研究了C0(Ac)2·4H2O,Ni(Ac)24H2O,Cu(Ac)2·H2O,Zn(Ac)2·2H2O与邻菲咯啉在室温(20土2℃)条件下的固相配位化学反应,讨论了反应物分子结构对固相反应的影响,通过固相反应一步合成了相应的配合物,经元素分析、红外光谱,X-射线衍射测定,确定了固相合成产物的组成。 相似文献
166.
DTA, TG, XRD and IR methods were used to study the formation of solid solutions in the selected subsolidus range of the PbZrO3-K0.5Bi0.5TiO3 system by heating mixtures prepared using oxide substrates, i.e. PbO, Bi2O3, ZrO2, TiO2 and K2CO3. It was found that solid solutions are formed in the reaction of PbO and ZrO2 with intermediate compound, i.e. K0.5Bi0.5TiO3. PbZrO3 was not found to be formed as an intermediate phase.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
167.
Determination and removal of sulfonamides and quinolones from environmental water samples using magnetic adsorbents 下载免费PDF全文
Hao Wu Yating Shi Xiaozhen Guo Shuangli Zhao Juanli Du Hongping Jia Lina He Liming Du 《Journal of separation science》2016,39(22):4398-4407
In this study, the magnetic materials known as polymerized ionic liquid@3‐(trimethoxysilyl)propyl methacrylate@Fe3O4 nanoparticles were synthesized and utilized as potential adsorbents. First, these nanoparticles were applied to the analysis of sulfonamides and quinolones present in different water samples using magnetic solid phase extraction and high‐performance liquid chromatography. Under optimized conditions, the developed method showed excellent detection sensitivity, with limits of detection (S/N = 3) and quantification limits (S/N = 10) within 0.2–1.0 and 0.8–3.4 μg/L, respectively. The spiked recoveries of the SAs and QNs in environmental water samples ranged from 83.5 to 103.0%, with RSDs of less than 4.5%. In addition, the adsorbents effectively removed sulfamethoxazole and ofloxacin present in existing aquatic environments. The adsorption kinetics and isotherms of sulfamethoxazole and ofloxacin on the magnetic adsorbents were studied to assess removal performance. The results indicate that the adsorption process follows a pseudo‐second‐order mechanism, which reveals that the sorption mechanism is the rate‐limiting step and produces high qmax values (sulfamethoxazole = 70.35 mg/g and ofloxacin = 48.95 mg/g), thus demonstrating the enormous adsorption capacity of these magnetic adsorbents. 相似文献
168.
《Journal of separation science》2017,40(17):3479-3486
Herein, an amino‐based silica‐coated nanomagnetic sorbent was applied for the effective extraction of two chlorophenoxyacetic acids (2‐methyl‐4‐chlorophenoxyacetic acid and 2,4‐dichlorophenoxyacetic acid) from various water samples. The sorbent was successfully synthesized and subsequently characterized by scanning electron microscopy, X‐ray diffraction, and Fourier‐transform infrared spectroscopy. The analytes were extracted by the sorbent mainly through ionic interactions. Once the extraction of analytes was completed, they were desorbed from the sorbent and detected by high‐performance liquid chromatography with ultraviolet detection. A number of factors affecting the extraction and desorption of the analytes were investigated in detail and the optimum conditions were established. Under the optimum conditions, the calibration curves were linear over the concentration range of 1–250, and based on a signal‐to‐noise ratio of 3, the method detection limits were determined to be 0.5 μg/L for both analytes. Additionally, a preconcentration factor of 314 was achieved for the analytes. The average relative recoveries obtained from the fortified water samples varied in the range of 91–108% with relative standard deviations of 2.9–8.3%. Finally, the method was determined to be robust and effective for environmental water analysis. 相似文献
169.
《Journal of separation science》2017,40(22):4294-4302
A directly‐coupled‐column ultra‐fast liquid chromatography coupled with diode array detection method for the determination of 12 allergenic disperse dyes in river water at sub‐ppb levels has been developed and successfully validated. The analytical method is based on the use of two different reversed‐phased columns connected through a two‐position switching valve. A baseline separation was achieved by proper selection of stationary phases, mobile phases, and the use of a gradient elution in both dimensions. Furthermore, an easy‐to‐handle magnetic solid‐phase extraction procedure was developed for the preconcentration of 12 allergenic disperse dyes from river water. An enrichment factor of 100 times was obtained. The results showed excellent performance in terms of trueness (76.8–99.0%), precision (intraday: 2.2–8.0%, interday: 3.3–8.2%), and sensitivity (limits of determination, 0.027–1.46 μg/L). Twenty real samples collected from the outfalls in the Yaojiang, Yongjiang and Fenghuajiang estuary were analyzed, and three of the studied compounds were found in one collected sample (12.6 μg/L for disperse blue 7, 11.6 μg/L for disperse blue 106, and 0.22 μg/L for disperse blue 3). 相似文献
170.
新型磷钨酸基固体酸催化油酸酯化合成生物柴油 《燃料化学学报》2017,45(3):303-310
利用磷钨酸(PTA)与1,2,3-三氮唑-4,5-二羧酸(TDA)在水溶液中的反应,合成了一种新的固体酸TDA-PTA,采用X射线粉末衍射(XRD)、扫描电镜(SEM)、红外光谱(FT-IR)、热重(TG)以及电位滴定等方法对其进行了表征,并以油酸与甲醇的酯化反应为探针反应,考察了其催化性能,探讨了催化剂用量、醇酸物质的量比、反应时间、反应温度以及催化剂重复利用次数等对产物收率的影响。结果表明,TDA-PTA不仅保留有磷钨酸典型的Keggin结构,而且具有较强的酸强度;经修饰后,催化剂具有规整的球形形貌,比表面积明显大于磷钨酸;TDA-PTA在油酸与甲醇的酯化反应中表现出了优良的催化活性,尤其显示出好的重复利用性,六次使用后,仍得到86.8%的油酸甲酯产率,催化剂的物相以及Keggin结构没有明显变化。 相似文献