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991.
992.
He  Quan  Lei  Han  Luo  Suxin  Tang  Ping  Peng  Xin  Wang  Xi 《Research on Chemical Intermediates》2017,43(1):353-360
Research on Chemical Intermediates - Ischemia modified albumin detection has great significance in early diagnosis and treatment of myocardial ischemia. In this study, anti-IMA was immobilized on...  相似文献   
993.
Zhang  Jingbo  Sun  Chuanzhen  Li  Yajiao  Bai  Shouli  Luo  Ruixian  Chen  Aifan  Liu  Kun  Lin  Yuan 《Journal of Solid State Electrochemistry》2017,21(3):883-889
Journal of Solid State Electrochemistry - We report on the interfacial passivation mechanism in CdSe quantum dot-sensitized ZnO nanocrystalline thin film, where different sulfide semiconductors...  相似文献   
994.
995.
本文考虑了一类带拯救的两参数Markov碰撞过程.首先讨论了带拯救的两参数Markov碰撞q-矩阵发生函数的性质,通过发生函数给出了过程的正则性和唯一性判别准则,得到了过程的常返性和遍历性的充分必要条件,并给出了几个易于验证的充分条件.最后,给出了遍历情形下该过程平稳分布的发生函数,并给出了过程强遍历的判别准则.  相似文献   
996.
997.
Using two-colour visible (Vis)–ultraviolet (UV) photoionisation and pulsed field ionisation–photoelectron (PFI–PE) methods, we have obtained cleanly rotationally resolved photoelectron spectra for ZrO+(X 2Δ3/2,5/2; v+ = 0, 1, and 2). The rotation assignment of these state-to-state Vis–UV–PFI–PE spectra has allowed the unambiguous determination of the ground state term symmetry for ZrO+(X) to be 2Δ3/2, and the adiabatic ionisation energy of 90Zr16O, IE(90Zr16O) = 54,948.3(8) cm?1 [6.81272(10) eV]. The symmetry of the ionic ZrO+(X 2Δ3/2) ground state determined here disagrees with that reported in previous experiments. The rotational and vibrational constants determined in this experiment for the ionic 90Zr16O+(X 2Δ3/2) ground state are: Be+ = 0.4343(8) cm?1 and αe+ = 0.0019(5) cm?1, and ωe+ = 991.2(8) cm?1 and ωe+xe+ = 3.5(8) cm?1; and those for the ionic 90Zr16O+(X 2Δ5/2) excited spin-orbit state are: Be+ = 0.4357(6) cm?1 and αe+ = 0.0022(4) cm?1, and ωe+ = 991.9(8) cm?1 and ωe+xe+ = 3.6(8) cm?1, respectively. Based on the latter Be+ value, the equilibrium bond distances are determined to be re+ = 1.691(2) Å for 90Zr16O+(X 2Δ3/2) and re+ = 1.688(1) Å for 90Zr16O+(X 2Δ5/2). The IE(ZrO) along with the spectroscopic constants obtained here are valuable for benchmarking the ab initio quantum chemical calculations for energetic and structural predictions of ZrO/ZrO+.  相似文献   
998.
Theoretical studies on the thermodynamic and kinetic properties of the reactions of Ti+ with sulfur transfer reagent SCO via the C═S bond activation pathway have been carried on using DFT/B3LYP method, general statistical thermodynamics, and Eyring transition state theory with Wigner correction. The relevant reactions include reaction 1 4 Ti++1SCO → 4 IM 1 4 TS 1 4 IM 2 4 TiS++ 1 CO, and reaction 2 4Ti++1SCO →4IM1→ CP →2IM22TiS++1CO in which the spin multiplicity changes from the quartet state to the doublet state in the crossing region. It is concluded that the increase of the temperature is favored to the reaction 1 process, since the equilibrium constants (K) rises from 0.566 × 10[P]-9 at 200 K to 0.109 × 100 at 1200 K, and the reaction rate constant (k) from 0.222 × 100 s[P]-1 at 200 K to 0.540 × 10 11 s[P]-1 at 1200 K. Moreover, reaction 1 is endothermic, and non-spontaneous in the way the entropy increases, while reaction 2 is exothermic and spontaneous in the way their entropy decreases. The reaction path 2 is the energetically favorable channel, and its thermodynamic data change not largely with the rise of temperature.  相似文献   
999.
Abstract

Sixteen novel 3-methylthio-5-substituted benzamido-6-arylamino-1-phenyl-1H-pyrazolo[3,4-d]pyrimidin-4 (5H)-one derivatives (4a–p) were successfully synthesized from iminophosphoranes, aryl isocyanate, and substituted benzoylhydrazine. The structures of the title compounds were elucidated by FT-IR, 1H NMR, 13C NMR, and HRMS. Herbicidal activity of the compounds 4a–p against Brassica napus (rape), Echinochloa crusgalli (barnyard grass), Cucumis sativus (cucumber), and Triticum aestivum (wheat) were determined. The results showed that 5-(2-chlorobenzamido)-6-phenylamino-3-methylthio-1-phenyl-1H-pyrazolo[3,4-d]pyrimidin-4 (5H)-one (4c) displayed remarkable inhibition activity against the stalk and root of rape with 100% inhibition rate at the dosages of 10?mg/L and 100?mg/L, and 5-(4-nitrobenzamido)-6-phenylamino-3-methylthio-1-phenyl-1H-pyrazolo[3,4-d]pyrimidin-4 (5H) -one (4d) exhibited excellent activity against the stalk and root of barnyard grass with 100% inhibition rate at the same dosages.  相似文献   
1000.
Abstract

An efficient and green aqueous protocol to access 3-chalcogen benzo[b]furan derivatives has been developed. The reaction can proceed via I2-mediated intramolecular annulation reaction of 2-alkynylanisoles with diaryl disulfides (diselenides) in water or under solvent-free conditions at room temperature. With the participation of I2, a variety of 3-chalcogen benzo[b]furan derivatives were obtained in good to excellent yields. This reaction was considered to work via an iodocyclization cascade mechanism and the intermediate 3-iodo-2-phenylbenzofuran was detected by GC-MS.  相似文献   
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