超低功耗TV红外线控制收发器方案设计

使用MSP430F2xx系列芯片设计一种低功耗、低成本的IR红外远程控制收发器。详细介绍收发器完整的中断驱动。在静态模式下,消耗电流为0.1μA。软件设计中,在MSP430F21x1芯片上实现标准的红外控制协议RC5。该软件可以很方便地移植到其他的MSP430系列微处理器中。文中给出了系统软件设计流程图和硬件设计图。

Synthesis and Characterization of Condensed Polynuclear Aromatic Resin Derived from Ethylene Tar

As a kind of low-cost and readily available industrial byproduct, ethylene tar （ET） was for the first time utilized for the preparation of heat-resistant condensed polynuclear aromatic resin （COPNAR）. The basic properties of ET and the resulted COPNAR were characterized by FT-IR, IH-NMR, TGA and elemental analysis. The test results showed that ET with high aromatic content （〉50%） was suitable for the synthesis of COPNAR with superior heat resistance. The average molecular structure of ET was obtained by means of the improved Brown-Ladner method, and the reaction mechanism was considered as an acid-catalyzed positive ion-typed polymerization. Our findings have provided a new route to develop ET into technology-added heat-resistant resins.

Study on the flotation technology and adsorption mechanism of galena–jamesonite separation

In order to further separate the concentrate containing galena and jamesonite before undergoing hydrometallurgical process, flotation experiment was performed on the basis of mineralogical analysis.And the adsorption mechanisms of collector H on galena and jamesonite were also studied by FT-IR spectra analysis and molecular dynamics(MD) simulation. The flotation result shows that the efficient separation can be achieved with H as selective collector. Galena concentrated with Pb grade of 72.09%and Pb recovery of 50.96% was obtained, and jamesonite concentrated with Sb grade and recovery of10.89% and 76.67% respectively was obtained as well. Infrared spectrum analysis indicates that collector H can adsorb on the surface of galena and react with Pb2+to generate hydrophobic salt, while no evident adsorption phenomenon was observed on the surface of jamesonite. The MD simulation and calculation results demonstrate that adsorption energy of collector H on galena and jamesonite surface is à872.74 k J/mol and à500.538 k J/mol, respectively, which means collector H is easier to adsorb on the surface of galena than that of jamesonite.

Comparative Study of the Modification of Coal Tar Pitch for Higher Carbonization Yield and Better Properties

Parent coal tar pitch(CTP)was modified with boric acid(BA),cinnamaldehyde(CMA)and the mixture of BA and CMA,respectively.The parent CTP and three modified CTPs were characterized by elemental analysis,thermogravimetric analysis,Fourier transform infrared(FT-IR)spectroscopy and scanning electron microscopy.The four samples were carbonized at different temperatures and resultant carbonized products were characterized by FT-IR spectroscopy,X-ray diffraction and polarized-light microscopy.The results show that the morphologies and carbonization behaviors of the parent CTP and modified CTPs are quite different.The carbonization yield of the CTP modified with the mixture of BA and CMA is higher than that of CTP modified with BA or CMA only.In addition,the modification of CTP with 7 g of BA and 10 ml of CMA results in an increase in carbonization yield by5.64%.During the pyrolysis of modified CTPs,the dehydration of BA or the distillation of CMA occurs at the temperature lower than 300°C,and methyl and methylene groups of the modified CTPs disappear gradually as temperature rises.Furthermore,the modification of CTP by the mixture of BA and CMA results in more intensive mesophase spheres than other modified CTPs,and the modified CTP is easier to be carbonized to form graphitic carbon.

In-situ interaction of nano-PbS with gelatin

Water-soluble gelatin-PbS bionanocomposites （BNCs） were synthesized via a facile one-pot chemical reaction method at pH 7.40. The samples were characterized by transmission electron microscopy （TEM）, X-ray diffraction （XRD）, UV-vis absorption spectra （UV-vis）, Fourier transform infrared spectra （FT-IR） and circular dichroism （CD）. FT-IR data were used to envis- age the binding of PbS particles with oxygen atoms of carbonyl groups of gelatin molecule. The possible integration mechanism between gelatin and PbS was discussed in detail. The effect of Pb2＋ and PbS on the conformations of gelatin has also been analyzed by means of UV-vis, CD and FT-IR spectra, resulting in less c^-helix content and more open structures （[3-sheet, r-turn, or expanded）. A new formula to calculate the association constant was proposed according to the relationship between the absorbance of gelatin-PbS BNCs and the free concentration of PbS, and apparent association constants K （298/303/308 K： 3.11/2.00/1.60 × 10^6 tool/L） at three different temperatures were calculated based on this formula. Thermodynamic parameters such as AG^θ, △Hθ and △S^θ were also determined. The results of the thermodynamic investigations indicated that the reaction was spontaneous （AG^θ 〈 0）, and enthalpy-driven （△H^8 〈 0）.