武汉都市圈“光芯屏端网”产业集群协同创新网络特征及规划响应

基于产业链分工与合作视角,从上、中、下游各创新主体的空间分布和协同关系两方面分析武汉都市圈“光芯屏端网”产业集群协同创新网络的结构特征。研究结果表明:武汉都市圈“光芯屏端网”产业集群协同创新主体的空间分布整体呈现“核心—边缘”的圈层式集聚格局,其中上游协同创新主体的集聚程度最为显著;产业集群上、中、下游的协同创新网络发展不均衡,整体网络连通度不高,尚未形成完整稳定的结构。由此提出强化“一核”引领创新、突出“一廊”有机协同、链接节点聚核成圈、贯通产业协同闭环等规划策略,以期为提升武汉都市圈“光芯屏端网”产业集群协同创新能级提供相关参考。

Measurement of 3db Bandwidth of Laser Diode Chips

An accurate technique for measuring the frequency response of semiconductor laser diode chips is proposed and experimentally demonstrated.The effects of test jig parasites can be completely removed in the measurement by a new calibration method.In theory,the measuring range of the measurement system is only determined by the measuring range of the instruments network analyzer and photo detector.Diodes' bandwidth of 7 5GHz and 10GHz is measured.The results reveal that the method is feasible and comparing with other method,it is more precise and easier to use.

A 10 Gb/s laser diode driver in 0.35 μm SiGe BiCMOS technology

This paper discusses the design of a 10 Gb/s laser diode driver implemented in SiGe BiCMOS technology. The laser diode driver is composed of an input buffer, a predriver circuit and an output current switch stage. With the current mode logic （CML） structure, the input buffer and the predriver circuit have the capability of transmission and amplification of high speed data. By employing MOS-HBT cascode structure as the output stage, the laser diode driver exhibits very high speed and efficiency working at the 10 Gb/s data rate. The core circuit is operated under a 3. 3 V supply, while the output stage is operated under 5.5 V for sufficient headroom across the laser diode. The chip occupies a die area of 600 μm × 800μm. Measurements on chip show clear electrical eye diagrams over 10 Gb/s, which can well meet the specifications defined by SDH STM64/SONET OC192 and a 10 Gb/s Ethemet eye mask. Under a 5. 5 V supply voltage, the maximum output swing is 3.0 V with a 50 12 load （the corresponding modulation current is 60 mA）, and the total power dissipation is 660 mW.

Transmission spectrum method to measure the photonic bandgap of hollow-core photonic crystal fiber

A full-vector plane-wave method is introduced, particularly in calculating the photonic crystal in-plane photonic bandgap of a 2D triangular structure. Using numerical simulation, we can obtain the in-plane bandgap structure of a hollow-core photonic crystal fiber. In the experiments, we measured the transmission spectra of a hollow-core photonic crystal fiber and a silica rod. And using the numerical calculation we can get the relative transmission spectrum of a hollow-core photonic crystal fiber. Compared with the result of theoretical simulation, we found that they are in accordance with each other, i.e. they have the same bandgap in about the same normalized frequency.

New cobweb-structure hollow Bragg optical fibers

A new type of Bragg fibers, i.e. hollow-core cobweb-structured optical fibers, which can be used to the low-loss transmis- sion from visible to near infrared region (0.65 μm-1.55 μm), terahertz wave (200 μm-480 μm) and circular-polariza- tion-maintaining single-mode transmission are investigated. Results show that the hollow-core cobweb-structured fibers have less loss than other hollow-core Bragg fibers. The fibers can be constituted by using the plastics or glasses with large absorption losses.

Photonics-to-electronics integration for optical interconnects in the early 21^(st) century

We discuss the technical rationale,challenges,and potential for achieving “optics-to-the chip” via the intimate integration of photonics components such as lasers,detectors,and modulators with VLSI electronics.We review the progress made towards commercializing this technology for high-density optical transceivers and switching products.

Optimizing design of triplexer chip with low insert loss and high isolation based on planar lightwave circuit

Design optimization of a novel integrated triplexer based on planar lightwave circuit (PLC) for fiber-to-the-home applica- tions is described. The two-mode interference coupler and Mach-Zehnder interference are used to construct the filter chip. Simulation results of high isolation and low insertion loss are gotten for proposed design. Technique tolerance is improved for fabricating device.

Science Letters:Controllable high repetition rate gain-switchedNd:YVO_4 microchip laser

We demonstrated a monolithic, compact, diode-pumped gain-switched Nd:YVO4 laser at 1.064 μm wavelength with controllable repetition rate of 1 Hz to 25 kHz. Stable gain-switched pulse train with maximum repetition rate of 25 kHz and pulse width of 16 ns was obtained.

Research of Confocal Laser Induced Fluorescence Detection System for Micro-fluidic Chip

The characteristics such as signal noise ratio（SNR） and sensitivity of the fluorescence detection system for micro-fluidic chip influence the performance of the whole system extremely. The confocal laser induced fluorescence detection system is presented. Based on the debugging of optical and circuit modules, the results of detecting the samples are given and analyzed theoretically, and the improved project is put forward.

Adsorption Reaction Dynamics of Systems Lysozyme and Nanodiamond/Nanosilica at pH=7-13

Adsorption reactions between surfaces of nanodiamond and nanosilica with diameter of 100 nm prepared as suspension solutions of 0.25μg/μL and lysozyme molecule with different concentrations of 7 mmol/L PPBS at pH=7, 9, 11, and 13 have been investigated by fluores- cence spectroscopy. Adsorption reaction constants and coverages of lysozyme with different concentrations of 0-1000 nmol/L under the influences of different pH values have been ob- tained. Helicities and conformations of the adsorbed lysozyme molecules, free spaces of every adsorbed lysozyme molecule on the surfaces of nanopartieles at different concentrations and pH values have been deduced and discussed. The highest adsorption capabilities for both sys- tems and conformational efficiency of the adsorbed lysozyme molecule at pH=13 have been obtained. Lysozyme molecules can be prepared, adsorbed and carried with optimal activity and helicity, with 2 and 10 mg/m2 on unit nanosurface, 130 and 150 mg/g with respect to the weight of nanoparticle, within the linear regions of the coverages at around 150-250 nmol/L and four pH values for nanodiamond and nanosilica, respectively. They can be prepared in the tightest packed form, with 20 and 55 mg/m2, 810-1680 and 580-1100 mg/g at threshold concentrations and four pH values for nanodiamond and nanosilica, respectively.

Correlation between the gene expression profiles of adenocarcinoma of esophagus and Barrett’s esophagus

Objective： The aim of this study was to investigate the characteristics of gene changes from Barrett＇s esophagus （BE） to esophageal adenocarcinoma by cDNA microarray. Methods： The cDNA retro-transcribed from equal quantity mRNA from esophageal carcinoma and BE tissues as well as control normal epithelium of esophagus which were from one patient with esophageal adenocarcinoma were labeled with Cy5 and Cy3 fluorescence as probes. The mixed probes were hybridized with two pieces gene chip respectively. It was scanned by laser scanner Scan Array 4000. The acquired images were analyzed by software GenePix Pro 3.0. Results： A total of 214 genes were screened out which expression levels were more than 2 times in hybridization of esophageal adenocarcinoma vs normal epithelium of esophagus, whereas 90 genes in hybridization of BE vs normal epithelium. A parallel comparison among these two gene profiles showed that a total of 45 genes with 24 downregulation and 21 up-regulation which expression levels were more than 2 times between the BE and the esophageal adenocarcinoma. Among these, there were 27 genes with 18 downregulafion and 9 up-regulation which implicated the tendencies progressing from BE to esophageal adenocarcinoma. Conclusion： These genes or their products which implicate the tendencies can be chosen as indicators of carcinogenesis with high risk index for BE.

Microfabrication,surface modification,and laser guidance techniques to create a neuron biochip

In this report we illustrate our application of soft lithography-based microfabrication,surface modification,and our unique laser cell-patterning system toward the creation of neuron biochips. We deposited individual forebrain neurons from Day 7 embryonic chicks into two rows of eight in a silicon microstructure aligned over a microelectrode array (MEA). The polydimethylsiloxane (PDMS) membrane with microstructures to confine cells and guide network connectivity was aligned to the electrodes of a MEA. Both the MEA and the PDMS membrane were treated with O2 plasma,Poly-L-Lysine,and Laminin to aid in cell attachment and survival. The primary advantage of our process is that it is quicker and simpler than previous cell-placement methods and may make highly defined neuronal network biochips more practical.

Novel biosensor-based microarray assay for detecting rs8099917 and rs12979860 genotypes

AIM:To evaluate a novel biosensor-based microarray(BBM) assay for detecting rs12979860 and rs8099917 genotypes.METHODS:Four probes specific for rs8099917C/T or rs12979860G/T detection and three sets of quality control probes were designed,constructed and arrayed on an optical biosensor to develop a microarray assay.Two sets of primers were used in a one tube polymerase chain reaction(PCR) system to amplify two target fragments simultaneously.The biosensor microarray contained probes that had been sequenced to confirm that they included the rs8099917C/T or rs12979860G/T alleles of interest and could serve as the specific assay standards.In addition to rehybridization of four probes of known sequence,a total of 40 clinical samples collected from hepatitis C seropositive patients were also tested.The target fragments of all 40 samples were amplified in a 50 μL PCR system.Ten μL of each amplicon was tested by BBM assay,and another 40 μL was used for sequencing.The agreement of the results obtained by the two methods was tested statistically using the kappa coefficient.The sensitivity of the BBM assay was evaluated using serial dilutions of ten clinical blood samples containing 10 3-10 4 white cells/μL.RESULTS:As shown by polyacrylamide gel electrophoresis,two target segments of the interleukin 28Bassociated polymorphisms(SNPs) were successfully amplified in the one-tube PCR system.The lengths of the two amplified fragments were consistent with the known length of the target sequences,137 and 159 bps.After hybridization of the PCR amplicons with the probes located on the BBM array,the signals of each allele of both the rs8099917 SNPs and rs12979860 SNPs were observed simultaneously and were clearly visible by the unaided eye.The signals were distinct from each other,could be interpreted visually,and accurately recorded using an ordinary digital camera.To evaluate the specificity of the assay,both the plasmids and clinical samples were applied to the microarray.First,30 PCR amplicons of the various SNP alleles were hybridized on the BBM microarray.Full agreement between plasmids and the BBM assay was observed,with 30/30 correct matches(100%).The kappa value for the BBM assay with plasmids was 1.00(P < 0.05).For the 40 clinical blood samples,the BBM assay hybridization and direct sequencing results were compared for each amplicon.For patient blood samples,agreement was 28/28 for rs8099917T/T,9/11 for rs8099917T/G,1/1 for rs8099917G/G,24/24 for rs12979860C/C,11/14 for rs12979860C/T,and 2/2 for rs12979860T/T.Only five clinical samples of amplicon assay and direct sequencing results were discordant and heterozygotes:2/11 rs8099917T/G and 3/14 rs12979860C/T.The agreement of outcomes between BBM assay and direct sequencing for the detection of rs8099917 and rs12979860 was 95% and 92.5%,respectively;and the corresponding kappa values were 0.88 and 0.85(A kappa value > 0.75 was defined as substantial agreement).The BBM assay and sequencing had similar specificities for detection and identification of the two SNPs and their alleles.The sensitivity evaluation showed that the BBM assay could detect and identify SNP sequences present in blood samples containing as few as 10 2 white blood cells/μL.CONCLUSION:This biosensor microarray assay was highly specific,sensitive,rapid and easy to perform.It is compatible with clinical practice for detection of rs8099917 and rs12979860.

Transcriptomic analysis of Synechocystis sp. PCC6803 under low-temperature stress

In this study, cDNA microarrays were developed from 3569 mRNA reads to analyze the expression profiles of the transcriptomes of Synechocystis sp. PCC6803 under low temperature （LT） stress. Among the genes on the cDNA microarrays, 899 LT-affected genes exhibited a 1.5-fold （or greater） difference in expression compared with the genes from normal unstressed Synechocystis sp. PCC6803. Of the differentially expressed genes, 353 were up-regulated and 246 were down-regulated. The results showed that genes involved in photosynthesis were activated at LT （10℃）, including genes for photosystem I, photosystem II, photosynthetic electron transport, and cytochrome b6/f complex. Moreover, desg, one of four genes that encode the fatty acid desaturases, was also induced by LT. However, the LT conditions to some degree enhanced the transcription of some genes. In addition, LT （10℃） may reduce cellular motility by regulating the transcription of spkA （sll1575）, a serine/threonine protein kinase. The results reported in this study may contribute to a better understanding of the responses of the Synechocystis cell to LT, including pathways involved in photosynthesis and repair.

Near UV-pumped yellow-emitting Sr_9Mg Li(PO_4)_7:Eu^(2+) phosphor for white-light LEDs

Laboratory discovery of new phosphors for white-light light-emitting diodes （WLEDs） is still an im- perative challenge. A new yellow-emitting Sr9MgLi（PO4）7：Eu^2＋ phosphor was discovered based on the mineral-inspired pro- totype evolution and new phase construction strategy pro- posed by our group. Sr9MgLi（PO4）7：Eu^2＋ has been synthesized by using a high temperature solid-state method, and its phase structure and luminescence properties have been investigated in detail, and applied in WLED lamp. Sr9MgLi（PO4）7 phase is derived from the ]3-Ca3（PO4）2-type mineral structure. Upon 365 nm UV light excitation, the SrgMgLi（PO4）7：Eu^2＋ phosphor exhibits a broad emission band from 450 nm to 700 nm. The white-light LED lamp was fabricated based on the phosphor blends of the composition-optimized yellow-emitting Sr9MgLi （PO4）7：Eu2＋ and commercial blue-emitting BaMgAl10O17：Eu^2＋, and a 365 nm UV chip was used as the excitation source. The Ra, CCT value and CIE of the as-fabricated LEDs were found to be 83, 5,612 K, and （0.324, 0.358）, respectively. All the results indicate that Sr9MgLi（PO4）7：Eu^2＋ could be potential in the development of UV-pumped white-light LEDs.

Efficient broadband near-infrared phosphor Sr_(2)ScSbO_(6):Cr^(3+) for solar-like lighting

For healthy lighting,daily lighting that considers both visible light and near-infrared(NIR)light is necessary.However,at~900 nm,the extensively used solar-like phosphor-converted light-emitting diodes(pc-LEDs)are limited by a lack of high-performance NIR luminescent materials.We report a broadband NIR phosphor Sr_(2)ScSbO_(6):Cr^(3+) with a double perovskite-type structure,thus simultaneously demonstrating high luminescence efficiency and good thermal stability.Under 550-nm excitation,Sr_(2)ScSbO_(6):Cr^(3+) demonstrates broadband NIR emission centered at~890 nm with luminescence internal/external efficiencies of 82.0%/35.7%,respectively.Furthermore,the luminescence integrated intensity at 430 K remains at~66.4% of the initial intensity.We successfully fabricated pc-LED devices using a 465-nm-sized blue chip and other commercial phosphors,presenting a relatively complete solar-like spectrum from blue to NIR light and is expected to be used in solar-like lighting.

30 W monolithic 2-3 μm supercontinuum laser

A higfi-power all-fiber supercontinuum （SC） laser source based on germania-core fiber （GCF） was presented. The lesser absorption loss of GCF than silica fiber beyond 2.0 μm makes GCF more suitable for extending the SC spectrum to the long wavelength side. In this work, the GCF-based SC laser had a maximum power of 30.1 W, together with a 10 dB spectral bandwidth of 〉 1000 um spanning from 1.95 to 3.0 μm. To the best of our knowledge, this is the highest output power level ever reported for a GCF-based SC laser as well as a 2-3 μm SC laser.

Bionic SERS chip with super-hydrophobic and plasmonic micro/nano dual structure

Natural surface-enhanced Raman spectroscopy （SERS） chips based on plants or insects have gained increased attention due to their facile characteristics and low costs. However, such chips remain a major challenge for practical application because of poor reproducibility and stability as well as unavoidable damage to the surface structure during coating metal and uncontrolled dehydration. By using a simple wrinkling method, we develop a new route to fabricate a low-cost bionic SERS chip for practical detection. Inspired by the taro leaf, we fabricate a SERS chip with a super-hydrophobic and plasmonic micro/nano dual structure, and its structure parameters can be optimized. Compared with the natural taro-leaf SERS chip, our artificial chip exhibits Raman signals with an order of magnitude higher sensitivity （N 10-9 M） and enhancement factor （N 107） under the illumination of weak laser radiation, demonstrating that our SERS chip has great potential in biological detection. The excellent per- formances of our bionic SERS chip are attributed to a synergy of optimized micro-wrinkle and nano-nest, which is verified by experiment and simulation. We believe our bionic chip could be a promising candidate in practical application due to its merits such as simple fabricating process, optimizable structure, low cost, excellent homo- geneity, high sensitivity, and stability.