Research on Keyhole Diameter’s Vision Measurement Based on Parallel Technology

A keyhole diameter of the cartridge’s measurement based on machine vision is a part of the cartridge’s geometry measurement system, according to the system requirements, to complete the measurement within 5 seconds. A Image Collection System was constructed using computer, CCD camera, LED source, meanwhile a measurement system was compiled by C# on VS2010 platform based on machine vision. Use the Otsu algorithm to extracts the keyhole’s edge and near the pixels in order to reduce the computational Canny operator, and use parallel computing in the Canny operator to improve computing speed purposes. Use QueryPerformanceCounter timer for each module timing Canny operator, Canny operator improved computation time is reduced from the original 6s to nearly a hundred ms improved. Meet the time requirements of cartridge geometry measurement system, and other machine vision in which the project can be widely used

Synthesis, structure and photophysical properties of pyrene–based [5]helicenes : an experimental and theoretical study

Pyrene-cored [5]helicenes were prepared by a facile, efficient Wittig reaction and an intramolecular photocyclization reaction utilising 2,7-di-tert-butylpyrene-4-carbaldehyde and naphthalene/pyrene-based phosphorus ylides. Optical properties based on UV−vis absorption and fluorescence spectra were investigated. X-ray crystallography revealed that the pyrene-based [5]helicenes exhibited strong face-to-face π−π interactions and edge-to-face π−π interactions. HOMO and LUMO energies and molecular orbitals were also studied by density functional theory (DFT) calculations. This study has revealed that the torsion angle of the helical structure plays a role in determining the π−π interactions and the frontier molecular orbital energy levels. Thus, pyrene-based helicenes need to be considered when one designs new highly efficient organic light-emitting diodes and organic semiconductor materials

(R)-N-(3-Meth­oxy­phen­yl)-tert-butane­sulfinamide

The title compound, C11H17NO2S, was obtained by the reaction of (R)-tert-butane­sulfinamide with 3-meth­oxy­phenyl bromide in toluene. In the crystal, mol­ecules inter­act head-to-tail through N—H⋯O and C—H⋯O hydrogen bonds, forming one-dimensional chains parallel to the a axis

Verhulst Model of Interval Grey Number Based on Information Decomposing and Model Combination

Grey Verhulst models are often employed to simulate the development tendency with the characteristic of saturated process of S curve. However, the uncertainty of interval grey numbers will be increased since the boundaries of interval grey number are extended by the Axiom of nondecreasing grey degree in the existing Verhulst modeling method. In this paper, the interval grey number is divided into two real number parts, that is, “white” and “grey” parts. Then the “white” and “grey” parts are simulated and forecasted by building the grey Verhulst model and DGM (1, 1) model, respectively. To some degree, this method resolves the issue of amplifying the range of interval grey number. Finally, an example is used to compare the simulation performance between the new model and the traditional model, and the results show that the new model is superior to the other model

A novel fluorescence “on–off–on” chemosensor for Hg²⁺ via a water-assistant blocking heavy atom effect

Upper rim pyrene-functionalized hexahomotrioxacalix[3]arene L was synthesized via Click chemistry, and its fluorescence behaviors toward several common metal cations were investigated. L exhibited a significant fluorescence quenching response to Hg²⁺ in CH₃CN solution, which was unaffected by the coexistence of other competitive metal cations. Thus, L can be utilized as a highly selective and sensitive fluorescent chemosensor for Hg²⁺ with a detection limit in the nM level. Interestingly, the quenched fluorescence emission can be successfully revived upon the addition of water. In this process, the heavy atom effect of Hg²⁺ can be blocked by further coordination of a water molecule and resulted in the revival of the fluorescence emission of L/Hg²⁺ complex. Particularly, other polar solvents such as CH₃OH and CH₃CH₂OH also have the ability to revive the fluorescence emission of the L/Hg²⁺ complex, but on a much smaller scale than observed for H₂O. The heavy atom effect and blocking thereof were demonstrated within the same system by the use of a C₃-symmetric homooxacalix[3]arene scaffold. The present studies provided further evidence for the blocking heavy atom effect

Effects of steel slag application on greenhouse gas emissions and crop yield over multiple growing seasons in a subtropical paddy field in China

Asia is responsible for over 90% of the world's rice production and hence plays a key role in safeguarding food security. With China being one of the major global producers and consumers of rice, achieving a sustainable balance in maximizing crop productivity and minimizing greenhouse gas emissions from paddy fields in this country becomes increasingly important. This study examined the effects of applying steel slag, a residual product derived from the steel industry, on crop yield and CH4 and N2O emissions over multiple growing seasons in a Chinese subtropical paddy field. Average CH4 emission was considerably higher during the periods of rice crop growth compared to that during the periods of fallowing and vegetable crop growth, regardless of the amount of steel slag applied. When compared to the controls, significantly lower mean emissions of CH4 (1.03 vs. 2.34 mg m−2 h−1) and N2O (0.41 vs. 32.43 μg m−2 h−1) were obtained in plots with slag addition at a rate of 8 Mg ha−1 over the study period. The application of slag at 8 Mg ha−1 increased crop yields by 4.2 and 9.1% for early and late rice crops, respectively, probably due to the higher availability of inorganic nutrients such as silicates and calcium from the slag. Slag addition had no significant effect on the concentrations of heavy metals in either the soil or the rice grains, although a slight increase in the levels of manganese and cobalt in the soil and a decrease in the levels of manganese and zinc in the rice grains were observed. Our results demonstrate the potential of steel slag as a soil amendment in enhancing crop yield and reducing greenhouse gas emissions in subtropical paddy fields in China, while posing no adverse short-term impacts on the concentrations of heavy metals in the soil or the rice grains. However, long-term implications of this management practice and the cost/benefit remain unknown, so further studies to assess the suitability at large scale are warranted

Responses of greenhouse-gas emissions to land-use change from rice to jasmine production in subtropical China

We studied the impacts of an increasingly common change in land use from paddy field to jasmine fields on the emission of greenhouse gases (GHGs), which have supposed the transformation of more than 1200 ha only in the last decade in the surroundings of Fuzhou city in response to economic changes. The possible increases that this can suppose constitutes and environmental concern in China. We studied areas dedicated to rice crop that have been partially converted to jasmine cultivation with some parts still kept as rice fields. Emissions of CO2, CH4 and N2O varied significantly among the seasons. CO2 and CH4 cumulative emissions and the global-warming potential (GWP) of these emissions were significantly lower in the jasmine than the paddy field. N2O emission, N2O cumulative emission, however, were higher in the jasmine than the paddy field, despite in some concrete studied periods the differences were not statistically significant. The total decrease in GHG emissions from the conversion from rice to jasmine production was strongly influenced by the indirect effects of various changes in soil conditions. The expected changes due to the great differences in water and fertilization use and management and organic matter input to soil between these two crops were in great part due to modified soil traits. According to structural equation models, the strong direct effects of the change from rice to Jasmine crop reducing the emissions of CO2 and N2O were partially decreased by the indirect effects of crop type change decreasing soil pH and soil [Fe2+] for CO2 emissions and by decreasing soil salinity and soil [Fe3+] for N2O emissions. The negative effects of the crop conversion on CH4 emissions were mostly due to the globally negative indirect effects on soil conditions, by decreases in soil salinity, water content and [Fe2+]. Soil salinity, water content, pH, [Fe2+], [Fe3+] and [total Fe] were significantly lower in the jasmine than the paddy field, but temperature had the opposite pattern. CO2 emissions were generally correlated positively with salinity, temperature, and water content and negatively with [Fe3+] and [total Fe] in both fields. CH4 emissions were positively correlated with salinity, temperature, water content and pH in both fields. N2O emissions were positively correlated with temperature and were negatively correlated with water content, pH, [Fe2+], [Fe3+] and [total Fe] in both fields. CO2 was the most important GHG for the GWPs, and the total GWP was significantly lower for the jasmine than for the rice cropland field. The change in the land use in this area of paddy fields will decreased the global GHG emission, and the effect on the GWPs was mostly due to changes in soil properties

D-π-D chromophores based on dithieno[3,2-b:2′,3'-d]thiophene (DTT) : potential application in the fabrication of solar cell

In this work, four stable dithieno[3,2-b:2′,3'-d]thiophene-based π-extended molecules were designed and synthesized via a Pd-catalysed Sonogashira coupling reaction. The structures of these symmetrical compounds, including dithieno[3,2-b:2′,3'-d]thiophene (DTT) as the π-center and various donor (D) groups, were determined on the basis of NMR spectral data, elemental analysis, and X-ray crystallography. The photo-physical properties of the DTT-based derivatives 2 were fully investigated in both solution and solid state. The notable optical features of their solid-state powders showed significant red-shift in comparison with the luminescence of their dilute dichloromethane solutions. These results combined with the theoretical calculations indicate that they are promising candidates for the several applications in electronic and optoelectronic devices, as well as organic dyes for solar cells

Click synthesis of a quinoline-functionalized hexahomotrioxacalix[3]arene : a turn-on fluorescence chemosensor for Fe³⁺

A novel quinoline-functionalized hexahomotrioxacalix[3]arene L was synthesized via Click chemistry and its chemosensing properties with various metal ions were investigated. The chemosensor L exhibited a high selectivity for Fe³⁺ with little interference from other environmentally and biologically relevant metal ions, leading to a prominent ‘off-on’ type fluorescent signalling behaviour. Our studies demonstrated that the detection limit on fluorescence response of the sensor to Fe³⁺+ is in the 10⁻⁷ M range. The mechanism of the interaction between the L and Fe³⁺ has been investigated in detail by ¹H NMR spectroscopic titration experiments