- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Production of carbon dots during the liquid phase exfoliation of MoS2 quantum dots
摘要： In the long-distance migration of reindeer in winter, furs of reindeer foot, as the part in direct contacting with the external environment, can play the role of protection and heat preservation. With furs on different parts of the right posterior foot (fibular side, tibial side and planta pedis) as research objects, the microstructure of reindeer foot furs was observed with a scanning electron microscope. The image displayed that the reindeer foot furs was divided into 3 layers, namely cuticular layer, cortical layer and medulla layer. It was observed from the fur surface that the scales of fur on tibial side had smooth edge, with the scale structure in mosaic and coronary types. The scale structure of furs on the other parts showed the irregular waves due to abrasion to different degrees. From the cross-section view of fur, there was a non-medullated segment on the medial part of fur on planta pedis. The medulla layer of fibular and tibial sides showed a porous foam structure. The medulla index (MI) of fur on fibular side and tibial side at distal part was 70.35% and 81.79%, respectively, and MI at medial part was higher than that on other parts. The composition of reindeer foot fur was measured through infrared spectroscopy and energy spectrum analysis respectively. The element contents of foot fur varied on different parts. The content of sulfur of the furs on planta pedis was higher than that on other parts. The research results can provide foundations for the functional study and bionic design of reindeer foot furs during long distance migration and swimming.
关键词： structure and morphology,furs of reindeer foot,composition,functional analysis,experimental measurement
更新于2025-09-11 14:15:04
-
Kalman Filters - Theory for Advanced Applications || Applications of Kalman Filters for Coherent Optical Communication Systems
摘要： Correction to: Brahmi F, Khodir M, Mohamed C, Pierre D. Chemical Compostion and Biological Activities of Mentha Species. In: El-Shemy HA, editor. Aromatic and Medicinal Plants – Back to Nature. Rijeka: InTech; 2017. pp. 47-80. DOI: 10.5772/67291 The genus Mentha L. (Lamiaceae) is distributed all over the world and can be found in many environments. Mentha species, one of the world’s oldest and most popular herbs, are widely used in cooking, in cosmetics, and as alternative or complementary therapy, mainly for the treatment of gastrointestinal disorders like flatulence, indigestion, nausea, vomiting, anorexia, and ulcerative colitis. Furthermore, it is well documented that the essential oil and extracts of Mentha species possess antimicrobial, fungicidal, antiviral, insecticidal, and antioxidant properties. The economic importance of mints is also evident; mint oil and its constituents and derivatives are used as flavoring agents throughout the world in food, pharmaceutical, herbal, perfumery, and flavoring industry. To provide a scientific basis for their traditional uses, several studies have been conducted to determine the chemical composition of mints and assess their biological activities. This chapter describes the therapeutic effects and uses of Mentha species and their constituents, particularly essential oils and phenolic compounds; some additional biological activities will also be considered.
关键词： Mentha sp.,biological activities,composition,uses,therapeutic effects
更新于2025-09-11 14:15:04
-
Effects of laser-textured surface pattern on the wetting behavior and composition optimization of brazing filler: experimental study and numerical simulation
摘要： To reduce interface brittle compounds of brazed joints, laser-textured surface pattern was used instead of excessive active element to enhance the wetting behavior of brazing filler on Ti3SiC2 ceramic substrate. The cylindrical surface pattern was designed by theoretical calculation and examined by numerical simulation. The numerical simulation results showed that the cylindrical surface pattern can not only effectively reduce the wetting angle on the substrate surface, but also greatly accelerate the spreading process of brazing filler. The results of wetting experiment showed that the wettability of Ag–Cu–2Ti (wt.%) brazing filler on Ti3SiC2 with cylindrical surface pattern sufficiently increased compared with that on smooth surface, which were consistent with the theoretical calculation and numerical simulation results. The titanium content in Ag–Cu–Ti that suitable for the brazing of Ti3SiC2 even could be reduced from 4.5 to 2.0 wt.%. The novel method provides a feasible route for promoting the wetting behavior and achieving composition optimization of brazing filler.
关键词： Ceramics,Wetting,Composition optimization,Surface pattern
更新于2025-09-11 14:15:04
-
Investigation on the effect of indium composition on ultrafast carrier dynamics in InGaN alloys
摘要： In this letter, we investigated the effect of indium composition on carrier relaxation mechanisms in InGaN alloys. Four high quality alloys with indium composition from 25% to 75% were fabricated using energetic neutral atomic-beam lithography/epitaxy molecular beam epitaxy. Using sub-picosecond resolved photoluminescence at high carrier density, it was found the effective carrier lifetime extends with increasing indium composition. Moreover, the calculated initial carrier temperature also rises with higher indium composition. These results are consistent with the theoretical prediction that a greater phonon bandgap could reduce the carrier cooling rate to a certain extent via hot carrier bottleneck effect.
关键词： InGaN alloys,indium composition,carrier dynamics,photoluminescence,molecular beam epitaxy
更新于2025-09-10 09:29:36
-
[IEEE IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Valencia, Spain (2018.7.22-2018.7.27)] IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - The Use of Satellite Data in the Copernicus Atmosphere Monitoring Service (Cams)
摘要： The Copernicus Atmosphere Monitoring Service (CAMS) is one of the six thematic services of the European Union's flagship Earth Observation programme Copernicus. CAMS is implemented by the European Centre for Medium-Range Weather Forecasts (ECMWF) together with a network of about 60 entities distributed in 20 European countries: it is thus a truly international and collaborative effort. CAMS delivers operationally a wide range of information products and services on air quality, emissions and surface fluxes, solar radiation and climate forcings. All CAMS atmospheric composition outputs are unrestricted and provided free-of-charge to users worldwide. The CAMS global forecasting system is using ECMWF's Integrated Forecasting System (IFS), which is used successfully for Numerical Weather Prediction and has been extended with modules for atmospheric chemistry, aerosols and greenhouse gases. Over 60 different satellite data streams are assimilated to provide twice daily global atmosphere composition forecasts.
关键词： emissions,atmospheric composition,Copernicus,solar radiation,air quality
更新于2025-09-10 09:29:36
-
Circannual changes in major chemical composition of bulk dromedary camel milk as determined by FT-MIR spectroscopy, and factors of variation
摘要： We monitored the major chemical composition of bulk dromedary camel milk by FT-MIR spectroscopy over a 5-year period. The results highly correlated with those determined with reference methods (r > 0.985, p < 0.001). Production parameters showed significant (p < 0.001) seasonal and yearly changes. The overall mean fat, protein, lactose, solids-not-fat, and total solids concentrations of bulk dromedary camel milk were 2.87%, 2.94%, 4.15%, 8.00%, and 10.69%, respectively. Month of the year, year of the study, and level of production had a strong influence on bulk milk chemical composition and yield of milk components; however, the relative effect of season on composition was greater (proportion of variance app. 50%) compared to that of other factors of variation. The highest and lowest values were measured during winter and summer, respectively. Circannual variation in major milk components was associated with environmental conditions (photoperiod, temperature), whereas it was independent of nutritional factors.
关键词： Dromedary,Raw milk,Seasonal variation,Chemical composition,Camel
更新于2025-09-10 09:29:36
-
Validation of a Terminally Amino Functionalized Tetra-Alkyl Sn(IV) Precursor in Metal-Organic Chemical Vapor Deposition of SnO <sub/>2</sub> Thin Films: Study of Film Growth Characteristics, Optical, and Electrical Properties
摘要： Tin(IV) oxide is a promising semiconductor material with leading-edge properties toward chemical sensing and other applications. For the growth of its thin films, metal–organic chemical vapor deposition (MOCVD) routes are advantageous due to their excellent scalability and potential to tune processing temperatures by careful choice of the reactants. Herein, a new and highly efficient MOCVD process for the deposition of tin(IV) oxide thin films employing a terminally amino alkyl substituted tin(IV) tetra-alkyl compound is reported for the first time. The liquid precursor, tetrakis-[3-(N,N-dimethylamino)propyl] tin(IV), [Sn(DMP)4], is thermally characterized in terms of stability and vapor pressure, yielding highly pure, polycrystalline tin(IV) oxide thin films with tunable structural and morphological features in the presence of oxygen. Detailed X-ray photoelectron spectroscopy (XPS) analysis reveals the presence of oxygen vacancies and high amounts of chemisorbed oxygen species. Based on these promising features, the MOCVD process is optimized toward downscaling the thickness of tin(IV) oxide films from 25 to 50 nm to study the impact of incipient surface morphological changes occurring after initial thin-film formation on the electrical properties as investigated by van der Pauw (vdP) resistivity measurements. Optical bandgaps of thin films with varying thicknesses are estimated using ultraviolet–visible (UV–vis) spectroscopy.
关键词： composition,SnO2,morphology,MOCVD,resistivity
更新于2025-09-10 09:29:36
-
[IEEE 2018 Conference on Precision Electromagnetic Measurements (CPEM 2018) - Paris, France (2018.7.8-2018.7.13)] 2018 Conference on Precision Electromagnetic Measurements (CPEM 2018) - New Silicon Crystals for a Redefined Kilogram and Mole: Isotopic Composition of the First Two Crystals
摘要： The isotopic compositions (molar mass, M) of the first and new silicon crystals highly enriched in 28Si (> 99.99 %) used for the determination of the Avogadro constant were measured using a high resolution multicollector ICP mass spectrometer and applying a modified isotope dilution mass spectrometry technique. Relative uncertainties urel(M) < 1 × 10-9 were obtained: a reduction by almost three orders of magnitude in ten years. This study compares the homogeneities in M(Si) of the first “AVO28” crystal and the first crystal (Si28-23Pr11) of the “Kilogram-2” project.
关键词： isotopic composition,enriched silicon,Avogadro constant,mass spectrometry,“Kilogram-2” project,homogeneity
更新于2025-09-10 09:29:36
-
Raman scattering of impact diamonds
摘要： We report the results of a study of the polycrystalline powder of the diamond-lonsdaleite from the Popigai crater (Siberia) using UV micro-Raman spectroscopy and high-resolution synchrotron X-ray diffraction. By subtracting two experimental Raman spectra of diamond-lonsdaleite samples with close amounts of diamond and lonsdaleite, we were able to identify the polytypic composition of impact diamonds in contrast to the method of X-ray diffraction. We have managed to get for the first time the spectrum of "pure" lonsdaleite. Its deconvolution has allowed us to identify all the three Raman - active vibrational modes E2g, A1g, and E1g whose positions agree well with the results of ab initio calculations.
关键词： Raman scattering,polytypic composition,impact diamonds,synchrotron X-ray diffraction,lonsdaleite,UV micro-Raman spectroscopy
更新于2025-09-10 09:29:36
-
Design of Controllable Novel Piezoelectric Components for Microfluidic Applications
摘要： This paper reviews recent investigations and achievements in the design of controllable functional components for improving microfluidic systems, its effectiveness, and functionality. The main purpose was to design novel microstructures with piezoelectric properties (microresonators), which enable one to control the effectiveness of fluid flow in micro-hydro-mechanical devices for biomedical/biochemical purposes. Controllable properties were obtained by incorporating different types of binders in a piezoelectric ceramic matrix (lead zirconate titanate): polyvinyl butyral (PVB), poly methyl methacrylate (PMMA), and polystyrene (PS). The change in chemical composition of PZT helps to manipulate the piezoelectric characteristics, surface morphology, mechanical properties, etc., of the designed microfluidic element with the microstructure in it.
关键词： microfluidics,chemical composition,piezoelectric,periodical microstructure,microresonator
更新于2025-09-10 09:29:36