- 标题
- 摘要
- 关键词
- 实验方案
- 产品
过滤筛选
- 2019
- 2018
- 2015
- low-temperature electronics
- junction field-effect transistors
- Bessel Function
- Coupling Coefficient
- Fusion temperature and Elongation speed
- Infrared Thermography
- Statistical Analysis
- Mean Temperature Difference
- Surface temperature distribution
- Diabetic Foot Complications
- Optoelectronic Information Science and Engineering
- Electronic Science and Technology
- Physics
- Don State Technical University
- China Jiliang University
- UIN Suska Riau
- BMS College of Engineering
- Dalhousie University
- Majmaah University
- Soochow University
- University of Riau
- Karnataka Institute of Endocrinology and Research (KIER)
- Southern Federal University
-
Intrinsic and Extrinsic Heavy Atom Effect on the Multifaceted Emissive Behavior of Cyclic Triimidazole
摘要： Since heavy halogen atoms can be used to tune the emissive properties of organic luminogens, the understanding of their role in the photophysics is fundamental for materials engineering. Here, the extrinsic and intrinsic heavy atom effects on the photophysics of organic crystals are separately evaluated by comparing cyclic triimidazole (TT) with its mono-iodo derivative (TTI) and its cocrystal with diiodotetrafluorobenzene (TTCo). Crystals of TT show room temperature ultralong phosphorescence (RTUP) originated from H-aggregation. TTI and TTCo display two additional long lived components whose origin is elucidated through single crystal X-ray and DFT-TDDFT studies. The results highlight the different effects of the I atom on the three phosphorescent emissions. Intrinsic heavy atom effects play a major role on molecular phosphorescence which is displayed at RT only for TTI. H-aggregate RTUP and the I···N XB induced phosphorescences on the other side depend only on packing features.
关键词： photophysics,co-crystal,room temperature phosphorescence,halogen bonding,time resolved spectroscopy
更新于2025-09-04 15:30:14
-
[Springer Theses] The Electronic Transitions of Molecular Oxygen || Temperature Effects on the Lifetime of O2(a1Δg)
摘要： The non-radiative deactivation of O2(a1(cid:2)g) and O2(b1(cid:3) + g) by solvent molecules has been a topic of intense and extensive research for almost half a century. The seminal interest derived in part from an unusually large effect of solvent and solvent deuteration on the lifetime of O2(a1(cid:2)g). The lifetime of O2(a1(cid:2)g), τ (cid:2), varies by 5 orders of magnitude in different solvents, and differences between H/D-isotopologues of the same solvent often exceed a factor of 20. The early reports on the subject were based on indirect probe-based measurements of τ (cid:2). Therefore, the interpretations were often misguided and afforded considerable controversy. With the advent of fast near-IR sensitive detectors in the late 1970s, it became possible to detect O2(a1(cid:2)g) phosphorescence with time-resolution. This facilitated the recording of an increasingly accurate set of data, which in turn, led to the development of ever more sophisticated theories. This effort culminated in the 1990’s with the development of an empirical model of electronic-to-vibrational (e-to-v) energy transfer. This model, which by now is widely accepted, focusses on the solvent as a “vibrational energy sink” that accept the excitation energy of O2(a1(cid:2)g) and O2(b1(cid:3) + g). In particular, the model accounts nicely for H/D solvent isotope effects on τ (cid:2) that are signi?cantly different from those observed on τ (cid:3). Nevertheless, as we shall see in the present chapter, it still has some important limitations.
关键词： electronic-to-vibrational energy transfer,solvent molecules,temperature effects,O2(a1(cid:2)g),non-radiative deactivation
更新于2025-09-04 15:30:14
-
A multi-step etch method for fabricating slightly tapered through-silicon vias based on modified Bosch process
摘要： In this paper, a multi-step etching method based on Bosch process was investigated to fabricate a slightly tapered via. The diameter of vias was scaled from 40 to 100 lm. Isotropic etching step was added into Bosch process to control the angle of the tapered vias. The slope angle could be adjusted by changing the time settings of isotropic etching step. The in?uence of the platen temperature was also studied. The passivation and etching steps are extremely sensitive to temperature. Silicon grass could be formed at low temperature. The two different processes of isotropic SF6 etching and Cl2/HBr etching were also compared. The wrinkles and cracks were observed on the surface after treatment with isotropic SF6 etching. The Cl2/HBr etching method is much better for removing the scallops.
关键词： platen temperature,Cl2/HBr etching,slightly tapered through-silicon vias,multi-step etch method,SF6 etching,isotropic etching,modified Bosch process
更新于2025-09-04 15:30:14
-
DLC deposition inside of a long tube by using the pulsed-DC PECVD process
摘要： In this study, the pulsed-DC PECVD deposition system was used to produce Diamond-like carbon (DLC) film on the internal surface of a long metal tube (200 cm in length and 10 cm in diameter) employed as the deposition chamber itself. Firstly, the features of plasma discharges and the temperature distribution along the tube external surface were studied using argon, silane, and acetylene. The experimental results demonstrate that a stable discharge can be established inside the tube. It was found that when the precursor gas is employed, a temperature gradient on the tube surface is formed. Secondly, PECVD experiments regarding DLC film deposition inside the inner surface of the tube are described. For this purpose, polished stainless steel and silicon wafer samples were mounted on the inside tube surface for subsequent analysis of the coatings. It was found that the growth rate and the structure properties of the DLC film varied along the axial direction of the tube. However, surfaces of DLC film with high sp3 content provided better tribological characteristics. These results were mainly attributed to complex processes of local dissociation and activation happened by collision between the electrons and neutrals.
关键词： Electric discharge,Coating inside of the tube,Temperature,PECVD,DLC
更新于2025-09-04 15:30:14
-
The study of quantum efficiency in PIN photodiodes in terms of temperature and capacitive effects under non-uniform illumination conditions
摘要： In this article the impacts of quantum efficiency and bandwidth of PIN photodiodes under non-uniform illumination conditions are investigated. An absorption region is divided into the number of arbitrary layers and the continuity equations for each layer are solved with assuming that the carrier’s drift velocity is constant in each layer. Also the impact of transit time and capacitive effects of bandwidth were studied with considering the bias voltage, width of absorption region and temperature. The results show that with considering the capacitive effects, the bandwidth is increased by increase in temperature and bias voltage. We observe the effect of incident optical radiation from two n and p sides and also its impact on bandwidth and quantum efficiency. The results show more impact of radiation from n region compared to p region.
关键词： Temperature,Capacitive effect,PIN photodiode,Quantum efficiency,Bandwidth
更新于2025-09-04 15:30:14
-
Effect of temperature on structural and optical properties of solvothermal assisted CdS nanowires with enhanced photocatalytic degradation under natural sunlight irradiation
摘要： Photocatalytic degradation of toxic dyes is an important topic across the globe. This paper reports the photocatalytic degradation of methylene blue (MB) dye using cadmium sulfide (CdS) nanowires as a photocatalyst under natural sunlight irradiation. The CdS nanowires were successfully synthesized by a solvothermal route using ethylenediamine as a solvent with a series of different reaction temperature from 160 to 200 °C for a fixed time of 24 h. Multiple characterization techniques were used to investigate the structural, morphology, optical and photocatalytic study of as-synthesized CdS samples. The XRD patterns reveal highly crystalline CdS nanomaterials with a hexagonal crystal structure. The FESEM and HRTEM observations clearly confirmed a large number of uniform nanowires grown in different directions and interconnected with each other. The stoichiometric ratio of Cd:S is almost 1:1, confirmed by EDS analysis. Room temperature PL spectra of CdS nanowires exhibit a narrow emission at a wavelength of 512 nm. The CdS nanowires synthesized at 200 °C shows the excellent photocatalytic performance with highest photodegradation efficiency has reached up to 98.75% within 20 min, under sunlight irradiation. The 93.06% and 89.10% photodegradation efficiency were observed in CdS nanowires synthesized at 180 °C and 160 °C, respectively. From these result, it is observed that the crystallite size and morphology of CdS nanowires are the influence factors for the photodegradation efficiency of MB dye. Furthermore, the mechanism of MB dye photodegradation using CdS nanowires was discussed. These CdS nanowires with high photocatalytic activity can be used for future in water pollutant degradation.
关键词： Hexagonal CdS,Solvothermal synthesis,MB dye degradation,Reaction temperature,Sunlight irradiation
更新于2025-09-04 15:30:14
-
Study of the system responsivity to measure the blackbody's temperature by optical pyrometry from 1200?K to 1570?K
摘要： This work presents a method that has been recently adopted in our laboratory to determine the temperatures of blackbody sources in the range of 1200–1570 K. The system uses a Double Monochromator System (DMS) based on a grating and a prism as dispersion elements. The detection element was a silicon photodiode (Si-MMA), over which the spectral range from 800 nm to 900 nm has been used. Between the blackbody source and the DMS was placed an optical system consists of two convergent lenses. The system responsivity “G ” was determined by the transmission factor of the optical system and the transmission factor of the DMS and the photodiode responsivity. The obtained results showed that the relative uncertainty of the system responsivity “G ” varied from 0.3% to 1.12%. This in turn resulted in a corresponding uncertainty in temperature of about 2.2 K and 4.5 K (k = 1) over the evaluated temperature range. Although this uncertainty level was signi?cantly high compared to those obtained by many other national metrology institutes, it was considered as a step forward in our laboratory to measure high temperatures.
关键词： temperature,detector,pyrometry,optical transmission,system responsivity
更新于2025-09-04 15:30:14
-
Analytical fitting of temperature-dependent spin-flip transitions in absorption spectra of Cr3+-doped silicate glasses
摘要： Temperature-dependent optical absorption spectra have been recorded for Cr3+ doped silicate glasses between 10 K and 773 K. Due to the intermediate ligand field strength of the Cr3+ coordination environment, overlap of the lowest-energy spin-allowed 4A2 → 4T2 band and the two spin-forbidden transitions to the 2E and 2T1 states at approximately 650 nm results in interference dips. An analytical model equation is fitted to the spectra and electronic structure parameters extracted. This represents the first time that variations of these parameters with temperature are obtained over a large temperature range, revealing characteristics of all three overlapping d-d transitions.
关键词： Chromium(III) doped glasses,absorption spectra,spectra calculations,interference dips,temperature
更新于2025-09-04 15:30:14
-
Fabrication of visual textile temperature indicators based on reversible thermochromic fibers
摘要： Human body signals detection functions in fibers such as visual temperature indicator, are important aspects in future development of satisfying the warmth and comfortableness of conventional textile fibers. A series of reversible thermochromic fibers (VTFs), where thermochromic microcapsules and polypropylene (PP) was used as color indicator and polymer fiber matrix, respectively, were prepared via melt spinning in this paper. The temperature-color response behaviors of VTFs were investigated in detail. The scanning electron microscopy (SEM) images of cross section of VTFs showed that PP was an excellent matrix for the dispersion of thermochromic microcapsules and no aggregation occurred. The results of color measuring and matching indicated that VTFs exhibited various colors of red, purple and blue depending on the mass ratio of the red function and blue function microcapsules. Moreover, when the ambient temperature changed between 5 °C and 35 °C, the color of VTFs could fade and recover in a short time, and this kind of VTFs displayed excellent performance stability after 60 temperature cycles.
关键词： Temperature indicator,Polypropylene,Cycling stability,Reversible thermochromic fibers
更新于2025-09-04 15:30:14
-
[IEEE 2018 International Conference on Current Trends towards Converging Technologies (ICCTCT) - Coimbatore, India (2018.3.1-2018.3.3)] 2018 International Conference on Current Trends towards Converging Technologies (ICCTCT) - Differential Pressure Sensor Using Silicon on Insulator Back to Back Cantilever Structure
摘要： In our day to day life differential pressure sensor can be used in much application. This type of pressure sensors are used for measuring the difference between two different pressure levels. Mostly bulk micro machined fabrication tool is used for fabrication process. Hence these type sensors have low cost and reliable than normal conventional sensor. This sensor is designed mainly to compare both the pressure below and above the liquid and flow rates and measures changes in pressure across restriction. The output differential pressure sensor varies with respect to the change in pressure level at up (or) down cantilever beam. When the pressure value at bottom side is high, when the membrane deflect towards forward direction (i.e.) moves upward. when the pressure value at which the bottom side is lower than the membrane deflects to backward direction (moves downward). This design is mainly used in domestic and industrial application.
关键词： Agriculture Applications,MEMS,Humidity Sensor,Temperature Sensor,Finite Element Method (FEM),micro-Cantilever
更新于2025-09-04 15:30:14