掺杂LaNiO3型双功能氧电极的研究--溶胶-凝胶制备方法

为了得到高性能的双效氧电极，研究了钙钛矿型掺杂LaNiO3电催化剂的溶胶-凝胶制备方法，通过热重-差热分析、红外分析、XRD分析以及催化剂的粒径分布分析等手段，探讨了pH值、柠檬酸用量以及焙烧制度对催化剂制备的影响。结果表明，制备LaNiO3的溶胶-凝胶法的最佳工艺条件是：柠檬酸的用量为金属离子总物质的量的1．5倍；pH值调节为9；焙烧制度为在750℃下焙烧2h。     

A 2 Gb/s optical receiver with monolithically integrated MSM photodetector in standard CMOS process

A monolithically standard complementary-metal-oxide-semiconductor (CMOS) optical receiver with a metal-semiconductor-metal (MSM) photodetector is presented in this paper.An active-feedback transimpedance amplifier (TIA) with negative Miller capacitance is used to increase the bandwidth of the receiver.The MSM photodetector with high responsivity provides higher sensitivity for the optical receiver.The optical receiver implemented in chartered 0.35 μm process achieves a 1.7 GHz bandwidth due to the low capacitance of the MSM photodetector.2 Gb/s optical data are successfully transmitted with a bit-error rate of 10-9 at an optical power of-15 dBm.The power consumption of the receiver is 94 mW under a single 3.3 V supply.     

双核多吡啶铂(Ⅱ)-紫精二元电子给受体体系的光诱导电子转移

设计合成了紫精(MV2+)桥连4′-(4-甲基-苯基)-2,2′:6′,2′′-三联吡啶铂(Ⅱ)(4-CH3-PhN^N^NPtCl)的双核配合物1,{[MV2+(4-CH2PhN^N^NPtCl)22+]·4PF6–}.利用紫外可见吸收光谱、发光光谱、电化学循环伏安谱以及瞬态吸收光谱研究了体系的光诱导电子转移过程,发现在乙腈/甲醇混合溶剂中该二元体系光诱导电子转移的速率常数kCS大于1.4×108s–1,电子回传的速率常数kCR大于2.1×103s–1,电荷分离态寿命长达479μs.     

Theoretical analysis and simulation of InP-based uni-traveling-carrier photodetector

In this paper the photocurrent response of InP-based uniotraveling-carrier photodetectors （UTC-PDs） is analyzed using the drift-diffusion approach. Based on the theoretical analysis, an InP/InGaAs UTC-PD is modeled utilizing a numerical device simulator （ATLAS）, and the physics of the device＇s operation and its performance as a function of biasing and power level are simulated. The simulation results indicate that the linear dynamic range is up to 60 mW, the f-3 dB is about 40 GHz and the full-width at half-maximum （FWHM） of the current pulse is 28 ps with 10 mW optical power injection for an optimized structure UTC-PD.     

A novel lambda negative-resistance transistor in the 0.5 μm standard CMOS process

A novel negative-resistance transistor (NRT) with a Lambda shaped I-V characteristic is demonstrated in the 0.5 μm standard CMOS process. To save on the number of component devices, this device does not use standard device models provided by CMOS processes, but changes a MOSFET and a BJT into a single device by fabricating them in the same n-well, with a p-type base layer as the MOSFET’s substrate. The NRT has a low valley current of -6.82 nA and a very high peak-to-valley current ratio of 3591. The peak current of the device is -24.49 μA which is low enough to reduce the power consumption of the deivce, and the average value of its negative resistance is about 32 kΩ. Unlike most negative-resistance devices which have been fabricated on compound semiconductor substrates in recent years, this novel NRT is based on a silicon substrate, compatible with mainstream CMOS technology. Our NRT dramatically reduces the number of devices, minimizing the area of the chip, has a low power consumption and thus a further reduction in cost.     

Photooxidation of Hantzsch 1,4-dihydropyridines by molecular oxygen

Photooxidation of Hantzsch 1,4-dihydropyridines (1,4-DHP, 1a–1d) by direct irradiation (λ > 300 nm) under an oxygen atmosphere has been carefully examined in this work. Spectroscopic and electrochemical studies demonstrate that photoinduced singlet electron transfer from 1,4-DHP to molecular oxygen occurs. The generated superoxide radical anion (O₂^–•) is responsible for this typical photochemical oxidation.     

“循环”投资的评价模型

为了解决循环投资的整体收益评价与优化问题,采用经典的投资评价方法对一次投资即单次循环投资的收益进行评价,根据循环投资中前次循环对后续循环资金的制约规律,得到了循环投资的总收益模型,并给出投资优化的方法。结果表明:对于循环投资而言,即使每次循环投资的期望收益为正,但如果多次投资,却不能保证总投资盈利,但可以利用模型中的优化公式,使得收益最大化或者损失最小。该结论对于进行金融投资或投机、企业资金管理等具有的参考价值和指导意义。     

C-H···Pd(II) interaction-driven homochiral M helix formation of neutral (R,R)-bis(pyrrol-2-ylmethyl- eneamino) cyclohexane palladium(II) complex

A chiral complex of (R,R)-Pd was prepared by reaction of optically pure (R,R)-bis(pyrrol-2-ylmethyl-eneamino) cyclohexane ligand with Pd(OAc)2·2H2O under the base condition at room temperature. The weak intermolecular C-H···Pd interaction was found to be responsible for the homochiral M helix for-mation of the neutral,chiral,mononuclear (R,R)-Pd in the crystal packing.     

聚乳酸/纳米二氧化硅原位复合材料的制备和性能

以丙交酯和改性后的纳米二氧化硅为原料,在辛酸亚锡催化作用下,制备了聚乳酸纳米二氧化硅复合材料。分别用红外光谱（FT-IR）,热失重分析（TG）,扫描电镜（SEM）等对其化学结构和性能进行了分析和表征。FT-IR和SEM分析表明,纳米二氧化硅与聚乳酸发生了化学结合,并且均匀的分散于聚乳酸基体中。TG结果表明,随着纳米二氧化硅含量的增加,聚乳酸纳米二氧化硅复合材料的热稳定性提高。通过力学性能分析可以看出无机纳米粒子的加入提高了材料的拉伸强度。     

AlGaInAs multi-quantum wells ring laser with optical coupling waveguides

Based on InAIGaAs multi-quantum wells epitaxy structure for Fabry-Pero laser diode, a multi-quantum wells semiconductor ring laser is realized using ICP dry etching process and polyimide planarization process, The laser is generated in a semiconductor resonator ring and is output by two coupled integrated bus waveguides. The ring diameter is 700μm and the width of the waveguide is 3 μm. The output optical power-current （P-I） characteristic and the wavelength spectra of the ring laser are measured using a fiber coupled to the cleaved facet of the bus waveguide. The threshold current of the device is 120 mA and the wavelength is 1602 nm at an injected current of 160 mA. In addition, the operation mode for the laser in the resonator ring is roughly discussed based on the P- I characteristic plot.