Studies on the toxicological effects of Asulox-40 and Emisan-6 to eggs and early life history stages of Sarotherodon mossambicus

Toxicological effects of Asulox-40 and Emisan-6 to eggs and early life history stages of Sarotherodon mossambicus were reported. 80% of egg hatching occurred in the controls, 1 p.p.m and 5 p.p.m concentrations of Asulox-40. 10 p.p.m. and 50 p.p.m. concentrations of the same toxicants had 70% and 60% hatchings while in Emisan-6 in the same concentrations the hatching were 70% and! 40%. In 100 p.p.m. concentration of both toxicants 20% incomplete hatching occurred. In Emisan-6 Lc 50 and Lc 100 values were recorded at 32 hand 96h respectively in 10 p.p.m. concentrations. In Asulox-40 the same values were recorded in 24h and 40h respectively at 50 p.p.m. concentration. The fish activity during the experimental period showed initial hyper activity. It was established that the Emisan-6 is more harmful to S. mossambicus than Asulox-40. The harmless concentrations of these chemicals were 1.2 p.p.m. for Asulox-40 and 0.6 p.p.m. for Emisan-6.

膜生物反应器-复合垂直流人工湿地(SMBR-IVCW)系统处理混合废水的应用研究

本文采用一体式膜生物反应器(SMBR)-复合垂直流人工湿地(IVCW)组合工艺(SMBR-IVCW)系统,研究了该系统对复合废水的净化效果。结果表明,当系统进水为CODCr397～890mg.L-1、氨氮9.40～27.1mg.L-1、TP4.30～10.7mg.L-1、TN45.9～75.8mg.L-1的条件下,在SMBR和IVCW的水力负荷分别为1000L.d-1和375mm.d-1的最优工况下运行,系统CODCr、NH3-N、TN和TP的去除率分别为97.5%、99.0%、59.6%和65.2%;系

A polymer waveguide-based 40 Gb/s optical bus backplane for board-level optical interconnects

Optical interconnects are increasingly considered for use in high-performance electronic systems. Multimode polymer waveguides are a promising technology for the formation of optical backplanes as they enable cost-effective integration of optical links onto standard printed circuit boards. In this paper, we present a 40 Gb/s optical backplane demonstrator based on the use of polymer multimode waveguides and a regenerative shared bus architecture. The system allows bus extension by cascading multiple polymeric bus modules through 3R regenerator units enabling the connection of an arbitrary number of electrical cards onto the bus. The proof-ofprinciple demonstrator reported here is formed with low-cost, commercially-available active devices and electronic components mounted on conventional FR4 substrates and achieves error-free 4×10 Gb/s optical interconnection between any two card interfaces on the bus. © 2013 IEEE.

A 40 Gb/s scalable optical polymer backplane using a regenerative shared bus architecture

The first multi-channel optical backplane demonstrator using on-board multimode polymer waveguides and a scalable shared-bus regenerative architecture is reported. The system allows bus extension by cascading multiple polymeric bus modules, and enables error-free 4×10 Gb/s interconnection between any two card interfaces on the bus.

40 Gb/s carrierless amplitude and phase modulation for low-cost optical datacommunication links

4 bps/Hz 40 Gb/s carrierless amplitude and phase (CAP) modulation is investigated for nextgeneration datacommunication links. The 40 Gb/s link achieves double the length of a conventional NRZ scheme, despite using a low-bandwidth source. © OSA/OFC/NFOEC 2011.

A 40 Gb/s optical bus for optical backplane interconnections

Optical technologies have received large interest in recent years for use in board-level interconnects. Polymer multimode waveguides in particular, constitute a promising technology for high-capacity optical backplanes as they can be cost-effectively integrated onto conventional printed circuit boards (PCBs). This paper presents the first optical backplane demonstrator based on the use of PCB-integrated polymer multimode waveguides and a regenerative shared bus architecture. The backplane demonstrator is formed with commercially-available low-cost electronic and photonic components onto conventional FR4 substrates and comprises two opto-electronic (OE) bus modules interconnected via a prototype regenerator unit. The system enables interconnection between the connected cards over four optical channels, each operating at 10 Gb/s. Bus extension is achieved by cascading OE bus modules via 3R regenerator units, overcoming therefore the inherent limitation of optical bus topologies in the maximum number of cards that can be connected to the bus. Details of the design, fabrication, and assembly of the different parts of this optical bus backplane are presented and related optical and data transmission characterisation studies are reported. The optical layer of the OE bus modules comprises a four-channel three-card waveguide layout that is compatible with VCSEL/PD arrays and ribbon fibres. All on-board optical paths exhibit insertion losses below 13 dB and intra-channel crosstalk lower than -29 dB. The robustness of the signal distribution from the bus inputs to all respective bus output ports in the presence of input misalignment is demonstrated, while 1 dB input alignment tolerances of approximately ±10 μm are obtained. The electrical layer of the OE bus modules comprises the essential driving circuitry for 1×4 VCSEL and PD arrays and the corresponding control and power regulation circuits. The interface between the optical and electrical layers of the bus modules is achieved with simple OE connectors that enable end-fired optical coupling into and out of the on-board polymer waveguides. The backplane demonstrator achieves error-free (BER < 10-12) 10 Gb/s data transmission over each optical channel, enabling therefore, an aggregate interconnection capacity of 40 Gb/s between any connected cards. © 1983-2012 IEEE.

Study of high performance re-timing using a 40 Gb/s hybrid-integrated mach-zehnder all-optical regenerator

We experimentally show that a hybrid-integrated Mach-Zehnder switch with a high performance gate profile allows retiming of optical signals with an accuracy of 500-700fs even if the input timing jitter is increased to 3ps. © 2004 Optical Society of America.

40 Gb/s 光电探测器小信号测试法和大信号测试系统研究

Submitted by 阎军 (yanj@red.semi.ac.cn) on 2010-06-21T07:30:12Z No. of bitstreams: 1 张邦宏--40 Gbs 光电探测器小信号测试法和大信号测试系统研究.pdf: 3057511 bytes, checksum: 0c2a4acd2c1687f6c3ee554b01030fed (MD5)

40-Gb/s Low Chirp Electroabsorption Modulator Integrated With DFB Laser

A 40-Gb/s monolithically integrated transmitter containing an InGaAsP multiple-quantum-well electroabsorption modulator (EAM) with lumped electrode and a distributed-feedback semiconductor laser is demonstrated. Superior characteristics are exhibited for the device, such as low threshold current of 20 mA, over 40-dB sidemode suppression ratio at 1550 nm, and more than 30-dB dc extinction ratio when coupled into a single-mode fiber. By adopting a deep ridge waveguide and planar electrode structures combined with buried benzocyclobutene, the capacitance of the EAM is reduced to 0.18 pF and the small-signal modulation bandwidth exceeds 33 GHz. Negative chirp operation is also realized when the bias voltage is beyond 1.6 V.

Fabrication of InGaAlAs MQW buried heterostructure lasers by narrow stripe selective MOVPE

Fabrication of InGaAlAs MQW buried heterostructure (BH) lasers by narrow stripe selective MOVPE is demonstrated in this paper. High quality InGaAlAs MQWs were first grown by narrow stripe selective MOVPE without any etching process and assessed by analysing the cross sections and PL spectrums of the InGaAlAs MQWs. Furthermore, BHs were fabricated for the InGaAlAs MQW lasers by a developed unselective regrowth method, instead of conventional selective regrowth. The InGaAlAs MQW BH lasers exhibit good device characteristics, with a high internal differential quantum efficiency of 85% and a low internal loss of 6.7 cm(-1). Meanwhile, narrow divergence angles of the far field pattern are obtained for the fabricated lasers.

40-GHz wavelength tunable mode-locked SOA-based fiber laser with 40-nm tuning range

A 40-GHz wavelength tunable mode-locked fiber ring laser based oil cross-gain modulation in a semiconductor optical amplifier (SOA) is presented. Pulse trains with a pulse width of 10.5 ps at 40-GHz repetition frequency are obtained. The laser operates with almost 40-nm tuning range. The relationship between the key laser parameters and the output pulse characteristics is analyzed experimentally.

基于CLIGEN和GCM模型预测未来40年黄土丘陵沟壑区的气候变化——以安塞为例

为预测3种温室气体排放情景(A2、B2和GGa1)下未来40年黄土丘陵沟壑区的气候变化,利用安塞试验站1986—2003年的气候观测资料以及1986—2049年GCM(HadCM3)栅格数据,通过空间转换和时间转换,利用CLIGEN和GCM模型,预测未来40年以安塞为代表的黄土高原丘陵沟壑区的气候变化。结果表明:与当前条件相比,到2049年,A2、B2和GGa1 3种情景下预测的降雨量分别增加37%、22%和12%;3种情景下预测的最大月均降雨量出现在夏季;到2049年,A2、B2和GGa1 3种情景下预测的月均最低气温和月均最高气温皆增加,但差异不明显,年均最低气温和年均最高气温分别增加1.41~1.56℃和0.92~1.57℃。

稀土-聚合物纳米复合材料的制备与表征

纳米材料以其特有的优异性能成为下一代信息技术、能源技术和生物医学技术的重要基础。纳米材料的研究是一个多学科交叉的领域，受到各国科学家及政府的极大重视，成为当前科学研究的热点前沿领域之一。近年来，无机纳米微粒与聚合物复合而成的无机-有机纳米复合材料可能成为集无机、有机、纳米等诸多材料的优良特性于一身的新型功能材料，倍受各国研究者的关注，对无机-有 机纳米复合材料的研究构成了当前纳米材料领域的新热点。我们在当今科学研究的前沿领域内，通过大量文献调研，选择稀土化合物为 目标化合物，开展了研究工作。采用新方法制备了ZnS、ZnS:Eu、ZnS:Mn、ZnS:Mn,Eu和CeO_2纳米微粒，制备了稀土硫化物、CeO_2纳米微粒与聚苯乙烯的纳米复合材料，对所制备的材料进行了表征，研究了反应过程及材料的发光特性，取得了一些创新性结果。1．首次采用固相法在接近室温和室温条件下，分别以硫代乙酰胺(TAA)和硫化钠为原料与醋酸锌进行反应，成功地制备出ZnS纳米微粒，通过XRD、TEM、SPS、荧光光谱等对样品进行了表征，通过差热分析对反应机理进行了研究，得到以下结论：(1)．ZnS纳米微粒具有立方面心结构，为闪锌矿型ZnS。发现TAA与醋酸锌通过低温固相法制备ZnS纳米微粒的最佳温度为100℃，低于此温度反应进行得不完全。提高反应温度将使ZnS纳米微粒的尺寸增大。(2)．100℃下合成的ZnS纳米微粒的晶粒粒径为3.2 nm，TEM观察到的每个ZnS纳米微粒是由更小的ZnS晶粒构成的多晶颗粒，平均颗粒尺寸为40 nm左右。(3)．TAA与醋酸锌反应的历程几乎同时经历了以下几个过程，其中包括TAA的熔融，TAA的分解并产生硫化氢，产生的硫化氢与醋酸锌反应生成醋酸及ZnS，醋酸的气化等，ZnS纳米微粒在上述过程中得以迅速生成，产生的气体物质起到了控制颗粒进一步生长的作用。2．首次采用低温固相法制备出掺杂的ZnS纳米微粒，ZnS:Eu、ZnS:Mn和ZnS:Mn，Eu，研究了制备条件对粒径及发光的影响。研究表明，灼烧温度对掺杂的ZnS纳米微粒的尺寸影响较大，温度升高粒径随之增大：灼烧时间及掺杂浓度对粒径影响很小。荧光光谱中出现了掺杂离子的特征发光，增大掺杂离子浓度及提高灼烧温度可使发光增强。3．首次发现ZnS:Mn纳米粒子经紫外光照射后出现了荧光增强现象。无论是波长为254 nm还是365 nm的紫外光照射后都可以观察到上述现象，并且发现在一定时间范围内，发光亮度随着照射时间的延长而增强。产生这种现象的原因可能是纳米微粒的表面态得到改善，使无辐射通道减少，因而辐射强度提高。4．首次采用表面光电压谱对ZnS纳米微粒进行了表征，观察到表面光电压谱发生了蓝移，ZnS纳米微粒有丰富的表面态。荧光光谱中观察到产生于表面态的陷阱荧光，并发生蓝移。5．采用W/O微乳液法，选用多种非离子型表面活性剂，成功地制备出粒径很小、颗粒均匀的CeO_2纳米晶，对制备过程中的影响因素(如灼烧温度、水与表面活性剂的摩尔比、Ce~(3+)的浓度、灼烧时间、表面活性剂种类等)进行了详细研究。结果如下：(1)．灼烧温度是影响CeO_2纳米微粒尺寸及形貌的关键因素。找到制备纯净的Ce02纳米晶的最佳温度为500℃，低于此温度CeO_2为无定形态，高于此温度则CeO_2纳米微粒的形貌规整但粒径增大。CeO_2纳米微粒的晶格畸变率随着灼烧温度的升高和粒径的增大而减小。(2)．W(水与表面活性剂的摩尔比)、Ce~(3+)浓度、灼烧时间、表面活性剂种类等也对CeO_2纳米微粒的尺寸有影响，但其影响小于灼烧温度的影响。(3)．首次在高分辨条件下通过TEM观察到CeO_2纳米晶的条纹相结构。6．首次将CeO_2纳米微粒与聚苯乙烯复合，成功地制备出CeO_2聚苯乙烯纳米复合材料，对材料进行了表征。(1)．CeO_2/聚苯乙烯纳米复合材料的IR光谱中有Ce-O键的振动吸收，且比通常CeO_2的Ce-O键的振动吸收向高能方向移动，说明CeO_2粒径较小。(2)．XPS谱中Ce的3d_(5/2)和3d_(3/2)结合能较CeO_2的标准谱向高能方向发生了移动，表明CeO_2与表面活性剂及聚苯乙烯之间存在着某种化学键作用。7．首次采用原位合成法制备出稀土硫化物聚苯乙烯纳米复合材料，并通过荧光光谱、磁性、光电子能谱、透射电镜等手段对它们进行了表征。研究了该复合材料的磁性质、荧光光谱、XPS谱、微结构与掺稀土聚苯乙烯相比发生的变化，分析了产生上述变化的原因。(1)．在掺Eu聚苯乙烯复合材料的激发光谱和发射光谱中可见Eu~(3+)的激发和发射峰。Eu~(3+)离子处于对称性很低的聚合物环境中，发射光谱中所出现的~5D_0 → ~7F_J(J = 0，l，2，3，4)跃迁的发射峰中~7F_l和~7F_2等能级解除简并发生了能级劈裂。随着Eu浓度增大，Eu~(3+)离子的发射峰强度增加。(2)．稀土硫化物聚苯乙烯纳米复合材料的发射光谱中在400 nm左右有宽带发射，且经紫外光照射后其发光强度降低，这是由于H_2S与Eu~(3+)发生而生成的不很稳定的Eu~(2+)经紫外光照射后被氧化成更为稳定的Eu~(3+)。(3)．稀土硫化物聚苯乙烯纳米复合材料和掺Eu聚苯乙烯复合材料相比，在荧光光谱、磁性、XPS谱和微结构等方面存在较大的差别。研究表明，在稀土硫化物聚苯乙烯复合材料中有较多的Eu~(3+)离子处于无反演对称性的格位，使得它的发射光谱在615 nm处的发光峰为最强；稀土硫化物聚苯乙烯纳米复合材料的饱和磁化强度较掺Eu聚苯乙烯复合材料的低；稀土硫化物聚苯乙烯纳米复合材料的球粒尺寸明显大于掺Eu聚苯乙烯复合材料的球粒尺寸，远大于纯聚苯乙烯的球粒尺寸。

近40年来珠江口的海平面变化

利用大万山附近1°×1°经纬度网格的卫星高度计资料（1993-2006），计算出