一种矩形波导打火检测装置的设计

介绍了一种矩形波导打火检测电路,分析了打火探测点的选取和光敏器件的选择。理论分析及计算的结论是：在矩形弯头波导窄壁中间选择了一个小孔作为打火探测点,选择光电二极管SFH250V作为光敏器件。以SFH250V为核心器件,设计了一种打火探测及故障快速锁存电路,主要解决了微弱光信号的探测问题,解决了微弱光电流信号的转换及放大问题,同时设计了打火故障判断及故障信号输出电路。实验表明,该装置可以有效地捕获较微弱的打火故障信号。     

Experiment and simulation of environmental chamber performance for fuel cell vehicle engine system

Journal of Thermal Analysis and Calorimetry - Comprehensive performance experiments were carried out, and the thermodynamic temperature simulation model was established based on the independently...     

A Novel Approach to the Stereoselective Synthesis of (E)-1-(1-Alkenyl)Benzotriazoles

The Horner-Wadsworth-Emmons olefination of diethyl-(1-benzotri-azolmethyl)phosphonate by means of aldehydes was found to be a convenient method for the stereoselective preparation of (E)-1-(1-Alkenyl)benzotriazoles.     

A Stereoselective Synthesis of (E)-Divinyl Diselenides and (E)-Divinyl Ditellurides

Insertion of elemental selenium or tellurium into the Csp²-Zr bond of alkenylchlorozirconocenes followed by oxidation in air affords (E)-divinyl diselenides or (E)-divinyl ditellurides.     

A New Synthesis of α-Aryltelluro Esters

Aryltellurenyl iodides react with Reformatsky reagents in dry THF at room temperature rapidly to produce α-aryltelluro esters in good yields.     

Tandem Reduction-Desulfonylation of α-Alkylidene-β-Keto Sulfones

α-Alkylidene-β-keto sulfones take place both reduction of carbon-carbon double bond and desulfonylation with the use of sodium hydrogen telluride in ethanol-N, N-dimethylformamide.     

Palladium-Catalyzed Cross-Coupling of Organozirconium Compounds with Diaryliodonium Salts

The palladium-catalyzed cross-coupling reaction of diaryliodonium salts with organozirconium compounds was achieved for about 1–1.5 hrs at room temperature and the reaction proceeded with retention of configuration to provide a new convenient method for the synthesis of (E)-disubstituted alkenes.     

Organophosphine/phosphite‐stabilized silver(I) complexes bearing N‐acetylbenzamide ligand: synthesis,characterization and potential application in metal organic chemical vapor deposition

New N‐silver(I) acetylbenzamide complexes of type L_n?AgNC₉H₈O₂ (L = PPh₃; n = 1, 2a; n = 2, 2b; n = 3, 2c; L = P(OEt)₃; n = 1, 2d; n = 2, 2e; n = 3, 2f) were prepared. These complexes were obtained in high yields and characterized by elemental analysis, ¹H NMR, ¹³C{H} NMR, ³¹P{H} NMR and IR spectroscopy, respectively. The molecular structure of 2b has been determined by X‐ray single‐crystal analysis in which the silver atom is in a distorted tetrahedral geometry and crystallizes as cis–trans. New N‐silver(I) acetylbenzamide complexes have a four‐membered ring, which could influence their chemical and physical properties and modulate volatility. Metal organic chemical vapor deposition experiments were carried out successfully at 400°C and 450°C using 2e as precursor for the deposition of silver films, respectively. The high‐purity silver film obtained at 400°C is dense and homogeneous. Copyright © 2012 John Wiley & Sons, Ltd.     

Isolation and Crystallographic Characterization of Two,Nonisolated Pentagon Endohedral Fullerenes: Ho3N@C2(22010)-C78 and Tb3N@C2(22010)-C78

Purified samples of Ho₃N@C₂(22010)-C₇₈ and Tb₃N@C₂(22010)-C₇₈ have been isolated by two distinct processes from the rich array of fullerenes and endohedral fullerenes present in carbon soot from graphite rods doped with Ho₂O₃ or Tb₄O₇. Crystallographic analysis of the endohedral fullerenes as cocrystals with Ni(OEP) (in which OEP is the dianion of octaethylporphyrin) shows that both molecules contain the chiral C₂(22010)-C₇₈ cage. This cage does not obey the isolated pentagon rule (IPR) but has two sites where two pentagons share a common C−C bond. These pentalene units bind two of the metal ions, whereas the third metal resides near a hexagon of the cage. Inside the cages, the Ho₃N or Tb₃N unit is planar. Ho₃N@C₂(22010)-C₇₈ and Tb₃N@C₂(22010)-C₇₈ use the same cage previously found for Gd₃N@C₂(22010)-C₇₈ rather than the IPR-obeying cage found in Sc₃N@D_3h-C₇₈.     

Stereoselective Synthesis and Application of (E)-α-Selanyl Vinylstannanes

The palladium-catalyzed reaction of acetylenic selenides with tributyltin hydride give verstile (E)-α-selanyl vinylstannanes regio-and stereoselectively. By iododestannylation, stereodefined(E)-α-iodo-selanyl alkenes have been synthesized.