Self-biting disease occurred in most farmed fur animals in the world. The mechanism and rapid detection method of this disease has not been reported. We applied bulked sergeant analysis (BSA) in combination with RAP...Self-biting disease occurred in most farmed fur animals in the world. The mechanism and rapid detection method of this disease has not been reported. We applied bulked sergeant analysis (BSA) in combination with RAPD method to analyze a molecular genetic marker linked with self-biting trait in mink group. The molecular marker was converted into sequence-characterized amplified regions (SCAR) marker for rapid detection of this disease. A single RAPD marker A8 amplified a specific band of 263bp in self-biting minks, which was designated as SRA8-250, and non-specific band of 315bp in both self-biting and healthy minks. The sequences of the bands exhibited 75% and 88% similarity to Canis familiarizes major histocompatibility complex (MHC) class II region and Macaca mulatta MHC class I region, respectively. A SCAR marker SCAR-A8 was designed for the specific fragment SRA8-250 and validated in 30 self-biting minks and 30 healthy minks. Positive amplification of SCAR-A8 was detected in 24 self-biting minks and 12 healthy minks. χ2 test showed significant difference (p〈0.01) in the detection rate between the two groups. This indicated that SRA8-250 can be used as a positive marker to detect self-biting disease in minks. Furthermore, the finding that self-biting disease links with MHC genes has significant implications for the mechanism of the disease.展开更多
Impact of amplified spontaneous emission(ASE)noise on the stimulated Raman scattering(SRS)threshold of highpower fiber amplifiers is demonstrated numerically through a spectral evolution approach.The simulation result...Impact of amplified spontaneous emission(ASE)noise on the stimulated Raman scattering(SRS)threshold of highpower fiber amplifiers is demonstrated numerically through a spectral evolution approach.The simulation results confirm that ASE noise in the Raman wavelength band could reduce the SRS threshold of high-power fiber amplifiers significantly.As for ASE noise originated the main amplifier,it becomes stronger and reduces the SRS threshold at shorter operation wavelength below 1052 nm.As for ASE noise originated from the seed laser,it reduces the SRS threshold at different operation wavelength under the condition that the Raman ratio is over-90 dB in the seed laser.The theoretical method and results in this work could provide a well reference to extend the operation wavelength of high-power fiber lasers.展开更多
An all-fiber polarization maintaining high-power laser system operating at 1.7 μm based on the Ramaninduced soliton self-frequency shifting effect is demonstrated. The entirely fiberized system is built by erbiumdope...An all-fiber polarization maintaining high-power laser system operating at 1.7 μm based on the Ramaninduced soliton self-frequency shifting effect is demonstrated. The entirely fiberized system is built by erbiumdoped oscillator and two-stage amplifiers with polarization maintaining commercial silica fibers and devices, which can provide robust and stable soliton generation. High-power soliton laser with the average power of 0.28 W,the repetition rate of 42.7 MHz, and pulse duration of 515 fs is generated directly from the main amplifier.Our experiment provides a feasible method for high-power all-fiber polarization maintaining femtosecond laser generation working at 1.7 μm.展开更多
In this paper,a simple adaptive power dividing function for the design of a dual-input Doherty power amplifier(DPA)is presented.In the presented approaches,the signal separation function(SSF)at different frequency poi...In this paper,a simple adaptive power dividing function for the design of a dual-input Doherty power amplifier(DPA)is presented.In the presented approaches,the signal separation function(SSF)at different frequency points can be characterized by a polynomial.And in the practical test,the coefficients of SSF can be determined by measuring a small number of data points of input power.Same as other dualinput DPAs,the proposed approach can also achieve high output power and back-off efficiency in a broadband operation band by adjusting the power distribution ratio flexibly.Finally,a 1.5-2.5 GHz highefficiency dual-input Doherty power amplifier is implemented according to this approach.The test results show that the peak power is 48.6-49.7d Bm,and the 6-d B back-off efficiency is 51.0-67.0%,and the saturation efficiency is 52.4-74.6%.The digital predistortion correction is carried out at the frequency points of 1.8/2.1GHz,and the adjacent channel power ratio is lower than-54.5d Bc.Simulation and experiment results can verify the effectiveness and correctness of the proposed method.展开更多
A Josephson traveling wave parametric amplifier(JTWPA),which is a quantum-limited amplifier with high gain and large bandwidth,is the core device of large-scale measurement and control systems for quantum computing.A ...A Josephson traveling wave parametric amplifier(JTWPA),which is a quantum-limited amplifier with high gain and large bandwidth,is the core device of large-scale measurement and control systems for quantum computing.A typical JTWPA consists of thousands of Josephson junctions connected in series to form a transmission line and hundreds of shunt LC resonators periodically loaded along the line for phase matching.Because the variation of these capacitors and inductors can be detrimental to their high-frequency characteristics,the fabrication of a JTWPA typically necessitates precise processing equipment.To guide the fabrication process and further improve the design for manufacturability,it is necessary to understand how each electronic component affects the amplifier.In this paper,we use the harmonic balance method to conduct a comprehensive study on the impact of nonuniformity and fabrication yield of the electronic components on the performance of a JTWPA.The results provide insightful and scientific guidance for device design and fabrication processes.展开更多
For time-of-flight(TOF)light detection and ranging(LiDAR),a three-channel high-performance transimpedance amplifier(TIA)with high immunity to input load capacitance is presented.A regulated cascade(RGC)as the input st...For time-of-flight(TOF)light detection and ranging(LiDAR),a three-channel high-performance transimpedance amplifier(TIA)with high immunity to input load capacitance is presented.A regulated cascade(RGC)as the input stage is at the core of the complementary metal oxide semiconductor(CMOS)circuit chip,giving it more immunity to input photodiode detectors.A simple smart output interface acting as a feedback structure,which is rarely found in other designs,reduces the chip size and power consumption simultaneously.The circuit is designed using a 0.5μm CMOS process technology to achieve low cost.The device delivers a 33.87 dB?transimpedance gain at 350 MHz.With a higher input load capacitance,it shows a-3 dB bandwidth of 461 MHz,indicating a better detector tolerance at the front end of the system.Under a 3.3 V supply voltage,the device consumes 5.2 mW,and the total chip area with three channels is 402.8×597.0μm2(including the test pads).展开更多
Head smut of maize (Zea mays L.), which was caused by Sporisorium reiliana, occurred in most of the maize growing areas of the world. The purpose of this study was to develop SCAR markers for map-based cloning of re...Head smut of maize (Zea mays L.), which was caused by Sporisorium reiliana, occurred in most of the maize growing areas of the world. The purpose of this study was to develop SCAR markers for map-based cloning of resistance genes and MAS. Two sets of BC3 progenies, one (BC3Q) derived from the cross Qi319 (resistance)×Huangzao 4 (susceptible), the other (BC3M) from Mol7 (resistance)× Huangzao 4 (susceptible), were generated. Huangzao 4 was the recurrent parent in both progenies. A combination of BSA (bulked segregant analysis) with AFLP (amplified fragment length polymorphism) method was applied to map the genes involving the resistance to S. reiliana, and corresponding resistant and susceptible bulks and their parental lines were used for screening polymorphic AFLP primer pairs. One fragment of PI3M61-152 was converted into SCAR (sequence charactered amplified fragment) marker S130. The marker was mapped at chromosome bin 2.09, the interval of a major QTL region previously reported to contribute to S. reiliana resistance. Furthermore, S130 was highly and facilitate map-based cloni associated with resistance to S. reiliana, and could be useful for marker-assisted selection ng of resistance genes.展开更多
The translucent endosperm trait in a japonica rice variety 'Kantou 194' is controlled by a Wx-mq gene which is allelic to Wx locus by genetic analysis and allelic test. The amylose content analysis showed that an in...The translucent endosperm trait in a japonica rice variety 'Kantou 194' is controlled by a Wx-mq gene which is allelic to Wx locus by genetic analysis and allelic test. The amylose content analysis showed that an intermediate amylose content between those of glutinous and non-glutinous rice existed in endosperm of homozygous Wx-mq genotype. The slight changes of amylose content in different varieties and F1 grains with an identical Wx-mq genotype might be influenced by dissimilar genetic background. To identify the Wx-mq genotype simply and rapidly, a cleaved amplified polymorphic sequence (CAPS) marker was designed. The result from the molecular detection indicated that it could be used for marker-assisted selection for low amylose content varieties in rice breeding.展开更多
This paper reports on the fabrication and characterization of a newly erbium-doped single-mode tellurite glass-fibre applicable for 1.5-μm optical amplifiers. A very broad erbium amplified spontaneous emission in the...This paper reports on the fabrication and characterization of a newly erbium-doped single-mode tellurite glass-fibre applicable for 1.5-μm optical amplifiers. A very broad erbium amplified spontaneous emission in the range 1450-1650 nm from erbium-doped single-mode tellurite glass-fibre is obtained upon excitation of a 980-nm laser diode. The effects of the length of glass-fibre and the pumping power of laser diode on the amplified spontaneous emission are discussed. The result indicates that the tellurite glass-fibre is a promising candidate for designing fibre-optic amplifiers and lasers.展开更多
An effective PCR protocol for detecting the sequence related amplified polymorphism (SRAP) in rice was developed. One hundred and ten pairs of SRAP primers were used for segregation analysis in an F2 population deri...An effective PCR protocol for detecting the sequence related amplified polymorphism (SRAP) in rice was developed. One hundred and ten pairs of SRAP primers were used for segregation analysis in an F2 population derived from a cross between Shennong 606 and Lijiangxintuanheigu. Among the 110 primer pairs, 35 pairs generated 143 polymorphic bands with an average of 4.09 polymorphic bands per primer pair, and 24 pairs (16.78%) showed the genetic distortion (P〈0.05). Of the 24 primer pairs, 12 pairs deviated toward the male parent Shennong 606 and 11 pairs toward the female parent Lijiangxintuanheigu, only one toward heterozygote. It was found that the segregation distortion might be caused by the joint gametic and zygotic effects.展开更多
We present an all-fiber 1.94μm nanosecond pulse laser in master oscillation-power amplifier configuration.A dual-FBGs gain-switched Tm^(3+)-doped fiber laser is built and is used as the seed laser.The output characte...We present an all-fiber 1.94μm nanosecond pulse laser in master oscillation-power amplifier configuration.A dual-FBGs gain-switched Tm^(3+)-doped fiber laser is built and is used as the seed laser.The output characteristics of the amplifier are studied at different pulse repetition rates,and the maximum output energy of 500μJ is achieved under incident pump power of 39 W.The emitting spectra are checked at 5 and 10 kHz,and no obvious nonlinear effects are observed in the spectrum of the amplified laser.The beam quality factor is M^(2)=2.1±0.03 measured by the traveling knife-edge method,and the laser beam spot is also monitored by an infrared vidicon camera.展开更多
To obtain a stable amplified spontaneous emission(ASE) source for complex environment applications, we design an ASE source and study the output power and spectral characteristics under different ambient temperature...To obtain a stable amplified spontaneous emission(ASE) source for complex environment applications, we design an ASE source and study the output power and spectral characteristics under different ambient temperatures.We optimize the structure of the ASE source to flatten the ASE spectrum, and study the output characteristics in terms of output power and optical spectrum under different pump powers. Then the performance of the ASE source is investigated in the temperature range from-18.9°C to 50°C. A stable-power and flat-spectrum ASE source can be obtained by structural optimization and pump control.展开更多
The purpose of the present study was to examine the genetic variation in Salamandra infraimmaculata from different breeding site habitats using the Amplified Fragment Length Polymorphism (AFLP) method. The results of ...The purpose of the present study was to examine the genetic variation in Salamandra infraimmaculata from different breeding site habitats using the Amplified Fragment Length Polymorphism (AFLP) method. The results of the dendogram from a hierarchical cluster analysis show that the grouping of S. infraimmaculata as cluster 5 differs from all the other clusters, including the St1 (Tel-Dan stream) population, which was the most predictable. Five Haplogroups (Hg) were characterized. The mean number of alleles per locus in each population (Ne) ranged from 10.566 (Sp1) to 2.720 (Po6). An average estimated heterozygosity (He) by population ranged from 0.100 (Po6) to 0.186 (St1). Population St1, a permanent breeding site where water was available all year round, exhibited the highest level of polymorphism, while population Po6, from the ephemeral breeding site, exhibited the lowest level of polymorphism. Gene flow between clusters showed that clusters 3 and 4 are sources of migrants and also receive gene flow, while clusters 1 and 2 may be a source of migrants but may not receive much gene flow. A phylogenetic analysis, based on clustering using Nei’s genetic distance, demonstrated that the Tel-Dan population is located on a separate branch within its sub-population. The conclusion of the present study shows that the genetic divergence among isolated populations is not correlated to distance but is affected by the variation of habitats.展开更多
A new approach to introducing a photoacid generator(PAG) into Langmuir-Blodgett (LB) films to draw photopatterns as a lithographic process is described here. The chemically amplified positive-tone resist system us...A new approach to introducing a photoacid generator(PAG) into Langmuir-Blodgett (LB) films to draw photopatterns as a lithographic process is described here. The chemically amplified positive-tone resist system used here consists of two components : a copolymer, poly ( dodecrylacrylamide-co-4-t-butyloxylvinyl-phenylcarbonate ) [ P ( DDA-t- BVPC53 ) ] and a PAG, tri (2,3-dibromopropyl) isocyanurate ( TDBPIC ). In the two-component system, the acid generated by the PAG catalyzes the deprotection reaction of P( DDA-t-BVPC53), to remove the tert-butoxycarbonyl group(t-BOC) in the exposed region during the postexposure baking process, thus rendering the exposed region soluble to alkaline aqueous solvents to form a positive tone. Photolithographic properties of the LB films have been evaluated. The patterns can be resolved with a resolution of 1 μm line width by UV irradiation, followed by development with an alkaline solution. The LB films can be used to generate etched gold relief images on a glass substrate via an aqueous iodide, like ammonium iodide, in alcohol/water as the etchant. The etch resistance of such LB films is sufficiently good, allowing patterning of a gold film suitable for photomask fabrication.展开更多
Amplified spontaneous emission (ASE), including intensity and bandwidth, in a typical example of BuEH-PPV is calculated. For this purpose, the intensity rate equation is used to explain the reported experimental mea...Amplified spontaneous emission (ASE), including intensity and bandwidth, in a typical example of BuEH-PPV is calculated. For this purpose, the intensity rate equation is used to explain the reported experimental measurements of a BuEH-PPV sample pumped at different pump intensities from Ip = 0.61 MW/cm2 to 5.2 MW/cm2. Both homogeneously and inhomogeneously broadened transition lines along with a model based on the geometrically dependent gain coefficient (GDGC) are examined and it is confirmed that for the reported measurements the homogeneously broadened line is responsible for the light-matter interaction. The calculation explains the frequency spectrum of the ASE output intensity extracted from the sample at different pump intensities, unsaturated and saturated gain coefficients, and ASE bandwidth reduction along the propagation direction. Both analytical and numerical calculations for verifying the GDGC model are presented in this paper. Although the introduced model has shown its potential for explaining the ASE behavior in a specific sample it can be universally used for the ASE study in different active media.展开更多
We investigate the effect of a metallic electrode on the ability for poly[2-methoxy-5-(2'-ethylhexyloxy)-1,4- phenylene vinylene] (MEH-PPV) film to undergo amplified spontaneous emission (ASE). The threshold of...We investigate the effect of a metallic electrode on the ability for poly[2-methoxy-5-(2'-ethylhexyloxy)-1,4- phenylene vinylene] (MEH-PPV) film to undergo amplified spontaneous emission (ASE). The threshold of the device with Ag cladding is about 10 times greater than that of a metal-free device, but metal such as Al completely shuts off ASE. The ASE recurs when a thin spacer layer, such as a few nanometers of SiO2, is introduced between the MEH-PPV film and the Al cladding. Compared with the Cu or Al electrode, the Ag cladding is most suited to serve as an electrode with its low optical loss due to its high work-function and reflectivity.展开更多
The polarization dependences of gain and amplified spontaneous Brillouin scattering(ABS) noise for fiber Brillouin amplifier(FBA) are analyzed through theories, simulations, and experiments.Modified vector propagation...The polarization dependences of gain and amplified spontaneous Brillouin scattering(ABS) noise for fiber Brillouin amplifier(FBA) are analyzed through theories, simulations, and experiments.Modified vector propagation equations for calculating the gain of the probe signal and the ABS noise are derived and analyzed in the Stokes spaces.In simulations and experiments, we prove that the gain of the probe signal and the ABS noise are strongly dependent on the relative state of polarization(SOP) of the pump and probe signals.The closer the relative SOP of the pump and probe signals is, the more obvious ABS noise suppression effect will be brought by increasing the power of the input probe signal.展开更多
The authors investigated size-dependent amplified spontaneous emission(ASE) from organic crystals. Specifically, N-(4-{4-[4-(diphenylamino)styryl]styryl}phenyl)-N-phenylbenzene amine(Ph-TPA2) organic crystals ...The authors investigated size-dependent amplified spontaneous emission(ASE) from organic crystals. Specifically, N-(4-{4-[4-(diphenylamino)styryl]styryl}phenyl)-N-phenylbenzene amine(Ph-TPA2) organic crystals were used in the experiment. The ASE threshold was decreased with the decrease of the width of the crystal at the same gain length, which reflects that total internal reflection plays an important role on the ASE properties in these slab organic crystals. The ASE properties pumped by one- and two-photon were also comparatively studied. We found that the thresholds of ASE in two-photon pumping condition are less size-dependent than those in singlephoton condition because of the nonlinear light generation processes in two-photon absorption processes.展开更多
In this work, performance enhancements of amplified spontaneous emission (ASE) from poly[2-methoxy-5-(2'- ethyl-hexyloxy)-l,4-phenylene vinylene] (MEH-PPV) have been achieved via solvent vapour treatment. Corre...In this work, performance enhancements of amplified spontaneous emission (ASE) from poly[2-methoxy-5-(2'- ethyl-hexyloxy)-l,4-phenylene vinylene] (MEH-PPV) have been achieved via solvent vapour treatment. Correlations between the morphology of the film and the optical performance of polymer-based ASE are investigated. The active layers are characterised by atomic force microscopy and optical absorption. The results show that the solvent-vapour treatment can induce the MEH-PPV self-organisation into an ordered structure with a smooth surface, leading to enhanced optical gain. Thus the solvent-vapour treatment is a good method for improving the optical properties of the MEH-PPV.展开更多
We investigate the amplified spontaneous emission (ASE) from an Ag-backed poly[2-methoxy-5-(2'-ethylhexyloxy)- 1,4-phenylenevinylene] (MEH-PPV) film with different film thicknesses. The ASE characteristics of A...We investigate the amplified spontaneous emission (ASE) from an Ag-backed poly[2-methoxy-5-(2'-ethylhexyloxy)- 1,4-phenylenevinylene] (MEH-PPV) film with different film thicknesses. The ASE characteristics of Ag-backed MEH- PPV films with different thicknesses show that increasing the film thickness can reduce the influence of the Ag cladding. The threshold, the gain, and the loss of the device with a thickness of 170 nm are comparable to those of a metal-free device. The lasing threshold of this device is about 7.5 times that of a metal-free device. Our findings demonstrate that Ag-backed MEH-PPV film with an appropriate thickness can still be a good polymer gain material for the fabrication of solid-state lasers.展开更多
文摘Self-biting disease occurred in most farmed fur animals in the world. The mechanism and rapid detection method of this disease has not been reported. We applied bulked sergeant analysis (BSA) in combination with RAPD method to analyze a molecular genetic marker linked with self-biting trait in mink group. The molecular marker was converted into sequence-characterized amplified regions (SCAR) marker for rapid detection of this disease. A single RAPD marker A8 amplified a specific band of 263bp in self-biting minks, which was designated as SRA8-250, and non-specific band of 315bp in both self-biting and healthy minks. The sequences of the bands exhibited 75% and 88% similarity to Canis familiarizes major histocompatibility complex (MHC) class II region and Macaca mulatta MHC class I region, respectively. A SCAR marker SCAR-A8 was designed for the specific fragment SRA8-250 and validated in 30 self-biting minks and 30 healthy minks. Positive amplification of SCAR-A8 was detected in 24 self-biting minks and 12 healthy minks. χ2 test showed significant difference (p〈0.01) in the detection rate between the two groups. This indicated that SRA8-250 can be used as a positive marker to detect self-biting disease in minks. Furthermore, the finding that self-biting disease links with MHC genes has significant implications for the mechanism of the disease.
基金the National Natural Science Foundation of China(Grant Nos.62005313 and 62061136013).
文摘Impact of amplified spontaneous emission(ASE)noise on the stimulated Raman scattering(SRS)threshold of highpower fiber amplifiers is demonstrated numerically through a spectral evolution approach.The simulation results confirm that ASE noise in the Raman wavelength band could reduce the SRS threshold of high-power fiber amplifiers significantly.As for ASE noise originated the main amplifier,it becomes stronger and reduces the SRS threshold at shorter operation wavelength below 1052 nm.As for ASE noise originated from the seed laser,it reduces the SRS threshold at different operation wavelength under the condition that the Raman ratio is over-90 dB in the seed laser.The theoretical method and results in this work could provide a well reference to extend the operation wavelength of high-power fiber lasers.
基金Supported by the National Natural Science Foundation of China (Grant Nos. 10225417 and 61675009)the Natural Science Foundation of Beijing Municipality (Grant Nos. 4204091 and KZ201910005006)the China Postdoctoral Science Foundation (Grant No. 212423)。
文摘An all-fiber polarization maintaining high-power laser system operating at 1.7 μm based on the Ramaninduced soliton self-frequency shifting effect is demonstrated. The entirely fiberized system is built by erbiumdoped oscillator and two-stage amplifiers with polarization maintaining commercial silica fibers and devices, which can provide robust and stable soliton generation. High-power soliton laser with the average power of 0.28 W,the repetition rate of 42.7 MHz, and pulse duration of 515 fs is generated directly from the main amplifier.Our experiment provides a feasible method for high-power all-fiber polarization maintaining femtosecond laser generation working at 1.7 μm.
基金supported by National Natural Science Foundation of China(No.62001061)。
文摘In this paper,a simple adaptive power dividing function for the design of a dual-input Doherty power amplifier(DPA)is presented.In the presented approaches,the signal separation function(SSF)at different frequency points can be characterized by a polynomial.And in the practical test,the coefficients of SSF can be determined by measuring a small number of data points of input power.Same as other dualinput DPAs,the proposed approach can also achieve high output power and back-off efficiency in a broadband operation band by adjusting the power distribution ratio flexibly.Finally,a 1.5-2.5 GHz highefficiency dual-input Doherty power amplifier is implemented according to this approach.The test results show that the peak power is 48.6-49.7d Bm,and the 6-d B back-off efficiency is 51.0-67.0%,and the saturation efficiency is 52.4-74.6%.The digital predistortion correction is carried out at the frequency points of 1.8/2.1GHz,and the adjacent channel power ratio is lower than-54.5d Bc.Simulation and experiment results can verify the effectiveness and correctness of the proposed method.
基金support from the Youth Innovation Promotion Association of Chinese Academy of Sciences (Grant No.2019319)support from the Start-up Foundation of Suzhou Institute of Nano-Tech and Nano-Bionics,CAS,Suzhou (Grant No.Y9AAD110)。
文摘A Josephson traveling wave parametric amplifier(JTWPA),which is a quantum-limited amplifier with high gain and large bandwidth,is the core device of large-scale measurement and control systems for quantum computing.A typical JTWPA consists of thousands of Josephson junctions connected in series to form a transmission line and hundreds of shunt LC resonators periodically loaded along the line for phase matching.Because the variation of these capacitors and inductors can be detrimental to their high-frequency characteristics,the fabrication of a JTWPA typically necessitates precise processing equipment.To guide the fabrication process and further improve the design for manufacturability,it is necessary to understand how each electronic component affects the amplifier.In this paper,we use the harmonic balance method to conduct a comprehensive study on the impact of nonuniformity and fabrication yield of the electronic components on the performance of a JTWPA.The results provide insightful and scientific guidance for device design and fabrication processes.
文摘For time-of-flight(TOF)light detection and ranging(LiDAR),a three-channel high-performance transimpedance amplifier(TIA)with high immunity to input load capacitance is presented.A regulated cascade(RGC)as the input stage is at the core of the complementary metal oxide semiconductor(CMOS)circuit chip,giving it more immunity to input photodiode detectors.A simple smart output interface acting as a feedback structure,which is rarely found in other designs,reduces the chip size and power consumption simultaneously.The circuit is designed using a 0.5μm CMOS process technology to achieve low cost.The device delivers a 33.87 dB?transimpedance gain at 350 MHz.With a higher input load capacitance,it shows a-3 dB bandwidth of 461 MHz,indicating a better detector tolerance at the front end of the system.Under a 3.3 V supply voltage,the device consumes 5.2 mW,and the total chip area with three channels is 402.8×597.0μm2(including the test pads).
基金funded by the National Hi-Tech R&D Program,China(863Program,2006AA100103,2007AA10Z172)the International Cooperation Project for Science and Technology(2007DFA31010)
文摘Head smut of maize (Zea mays L.), which was caused by Sporisorium reiliana, occurred in most of the maize growing areas of the world. The purpose of this study was to develop SCAR markers for map-based cloning of resistance genes and MAS. Two sets of BC3 progenies, one (BC3Q) derived from the cross Qi319 (resistance)×Huangzao 4 (susceptible), the other (BC3M) from Mol7 (resistance)× Huangzao 4 (susceptible), were generated. Huangzao 4 was the recurrent parent in both progenies. A combination of BSA (bulked segregant analysis) with AFLP (amplified fragment length polymorphism) method was applied to map the genes involving the resistance to S. reiliana, and corresponding resistant and susceptible bulks and their parental lines were used for screening polymorphic AFLP primer pairs. One fragment of PI3M61-152 was converted into SCAR (sequence charactered amplified fragment) marker S130. The marker was mapped at chromosome bin 2.09, the interval of a major QTL region previously reported to contribute to S. reiliana resistance. Furthermore, S130 was highly and facilitate map-based cloni associated with resistance to S. reiliana, and could be useful for marker-assisted selection ng of resistance genes.
基金supported by the National High Technology Research and Development Program of China(Grant No.2006AA100101)National Science and Technology Support Program of China(Grant No. 2006BAD01A01-5)+1 种基金Special Program for Rice Scientific Research,Ministry of Agriculture,China(Grant No. nyhyzx 07-001-006)Super Rice Breeding and Demonstration Program,Ministry of Agriculture,China and Jiangsu Agricultural Scientific Self-innovation Fund,China(Grant No.CX[07]603)
文摘The translucent endosperm trait in a japonica rice variety 'Kantou 194' is controlled by a Wx-mq gene which is allelic to Wx locus by genetic analysis and allelic test. The amylose content analysis showed that an intermediate amylose content between those of glutinous and non-glutinous rice existed in endosperm of homozygous Wx-mq genotype. The slight changes of amylose content in different varieties and F1 grains with an identical Wx-mq genotype might be influenced by dissimilar genetic background. To identify the Wx-mq genotype simply and rapidly, a cleaved amplified polymorphic sequence (CAPS) marker was designed. The result from the molecular detection indicated that it could be used for marker-assisted selection for low amylose content varieties in rice breeding.
基金Project supported by the National Natural Science Foundation 0f China (Grant Nos 50472053 and 60307004), National Century Elitist Table (Grant Nos 04-0821 and 04-0823) and Natural Science Foundation of Guangdong Province. (Grant Nos 04020036 and 2004A10602002).Acknowledgments We are grateful to Mrs Zhang W N, Feng Z M, Chen H and Chen B Y for their technical assistance.
文摘This paper reports on the fabrication and characterization of a newly erbium-doped single-mode tellurite glass-fibre applicable for 1.5-μm optical amplifiers. A very broad erbium amplified spontaneous emission in the range 1450-1650 nm from erbium-doped single-mode tellurite glass-fibre is obtained upon excitation of a 980-nm laser diode. The effects of the length of glass-fibre and the pumping power of laser diode on the amplified spontaneous emission are discussed. The result indicates that the tellurite glass-fibre is a promising candidate for designing fibre-optic amplifiers and lasers.
文摘An effective PCR protocol for detecting the sequence related amplified polymorphism (SRAP) in rice was developed. One hundred and ten pairs of SRAP primers were used for segregation analysis in an F2 population derived from a cross between Shennong 606 and Lijiangxintuanheigu. Among the 110 primer pairs, 35 pairs generated 143 polymorphic bands with an average of 4.09 polymorphic bands per primer pair, and 24 pairs (16.78%) showed the genetic distortion (P〈0.05). Of the 24 primer pairs, 12 pairs deviated toward the male parent Shennong 606 and 11 pairs toward the female parent Lijiangxintuanheigu, only one toward heterozygote. It was found that the segregation distortion might be caused by the joint gametic and zygotic effects.
基金the National Natural Science Foundation of China under Grant Nos 60878011 and 61078008the Program for New Century Excellent Talents in University under Grant No NCET-10-0067.
文摘We present an all-fiber 1.94μm nanosecond pulse laser in master oscillation-power amplifier configuration.A dual-FBGs gain-switched Tm^(3+)-doped fiber laser is built and is used as the seed laser.The output characteristics of the amplifier are studied at different pulse repetition rates,and the maximum output energy of 500μJ is achieved under incident pump power of 39 W.The emitting spectra are checked at 5 and 10 kHz,and no obvious nonlinear effects are observed in the spectrum of the amplified laser.The beam quality factor is M^(2)=2.1±0.03 measured by the traveling knife-edge method,and the laser beam spot is also monitored by an infrared vidicon camera.
基金Supported by the National Natural Science Foundation of China under Grant No 11504320
文摘To obtain a stable amplified spontaneous emission(ASE) source for complex environment applications, we design an ASE source and study the output power and spectral characteristics under different ambient temperatures.We optimize the structure of the ASE source to flatten the ASE spectrum, and study the output characteristics in terms of output power and optical spectrum under different pump powers. Then the performance of the ASE source is investigated in the temperature range from-18.9°C to 50°C. A stable-power and flat-spectrum ASE source can be obtained by structural optimization and pump control.
文摘The purpose of the present study was to examine the genetic variation in Salamandra infraimmaculata from different breeding site habitats using the Amplified Fragment Length Polymorphism (AFLP) method. The results of the dendogram from a hierarchical cluster analysis show that the grouping of S. infraimmaculata as cluster 5 differs from all the other clusters, including the St1 (Tel-Dan stream) population, which was the most predictable. Five Haplogroups (Hg) were characterized. The mean number of alleles per locus in each population (Ne) ranged from 10.566 (Sp1) to 2.720 (Po6). An average estimated heterozygosity (He) by population ranged from 0.100 (Po6) to 0.186 (St1). Population St1, a permanent breeding site where water was available all year round, exhibited the highest level of polymorphism, while population Po6, from the ephemeral breeding site, exhibited the lowest level of polymorphism. Gene flow between clusters showed that clusters 3 and 4 are sources of migrants and also receive gene flow, while clusters 1 and 2 may be a source of migrants but may not receive much gene flow. A phylogenetic analysis, based on clustering using Nei’s genetic distance, demonstrated that the Tel-Dan population is located on a separate branch within its sub-population. The conclusion of the present study shows that the genetic divergence among isolated populations is not correlated to distance but is affected by the variation of habitats.
基金Supported by a Grant-in-Aid for Scientific Research from the Japanese Ministry of Education, Sports, and Culture( No.14205130), and Natural Science Foundation of Henan Province(No. 0611020100)
文摘A new approach to introducing a photoacid generator(PAG) into Langmuir-Blodgett (LB) films to draw photopatterns as a lithographic process is described here. The chemically amplified positive-tone resist system used here consists of two components : a copolymer, poly ( dodecrylacrylamide-co-4-t-butyloxylvinyl-phenylcarbonate ) [ P ( DDA-t- BVPC53 ) ] and a PAG, tri (2,3-dibromopropyl) isocyanurate ( TDBPIC ). In the two-component system, the acid generated by the PAG catalyzes the deprotection reaction of P( DDA-t-BVPC53), to remove the tert-butoxycarbonyl group(t-BOC) in the exposed region during the postexposure baking process, thus rendering the exposed region soluble to alkaline aqueous solvents to form a positive tone. Photolithographic properties of the LB films have been evaluated. The patterns can be resolved with a resolution of 1 μm line width by UV irradiation, followed by development with an alkaline solution. The LB films can be used to generate etched gold relief images on a glass substrate via an aqueous iodide, like ammonium iodide, in alcohol/water as the etchant. The etch resistance of such LB films is sufficiently good, allowing patterning of a gold film suitable for photomask fabrication.
文摘Amplified spontaneous emission (ASE), including intensity and bandwidth, in a typical example of BuEH-PPV is calculated. For this purpose, the intensity rate equation is used to explain the reported experimental measurements of a BuEH-PPV sample pumped at different pump intensities from Ip = 0.61 MW/cm2 to 5.2 MW/cm2. Both homogeneously and inhomogeneously broadened transition lines along with a model based on the geometrically dependent gain coefficient (GDGC) are examined and it is confirmed that for the reported measurements the homogeneously broadened line is responsible for the light-matter interaction. The calculation explains the frequency spectrum of the ASE output intensity extracted from the sample at different pump intensities, unsaturated and saturated gain coefficients, and ASE bandwidth reduction along the propagation direction. Both analytical and numerical calculations for verifying the GDGC model are presented in this paper. Although the introduced model has shown its potential for explaining the ASE behavior in a specific sample it can be universally used for the ASE study in different active media.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 60978061,60777026,60677007,60825407,and 61036007)the Program for New Century Excellent Talents in University,China (Grant No. NCET-08-0717)+1 种基金the Beijing Municipal Science and Technology Commission (Grant Nos. Z090803044009001 and 4102046)the Program of Introducing Talents of Discipline to Universities,China (Grant No. B08002)
文摘We investigate the effect of a metallic electrode on the ability for poly[2-methoxy-5-(2'-ethylhexyloxy)-1,4- phenylene vinylene] (MEH-PPV) film to undergo amplified spontaneous emission (ASE). The threshold of the device with Ag cladding is about 10 times greater than that of a metal-free device, but metal such as Al completely shuts off ASE. The ASE recurs when a thin spacer layer, such as a few nanometers of SiO2, is introduced between the MEH-PPV film and the Al cladding. Compared with the Cu or Al electrode, the Ag cladding is most suited to serve as an electrode with its low optical loss due to its high work-function and reflectivity.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61531003,61690195,61701040,and 61427813)the Fund of State Key Laboratory of Information Photonics and Optical Communications,Beijing University of Posts and Telecommunications(BUPT),Chinathe Youth Research and Innovation Program of BUPT,China
文摘The polarization dependences of gain and amplified spontaneous Brillouin scattering(ABS) noise for fiber Brillouin amplifier(FBA) are analyzed through theories, simulations, and experiments.Modified vector propagation equations for calculating the gain of the probe signal and the ABS noise are derived and analyzed in the Stokes spaces.In simulations and experiments, we prove that the gain of the probe signal and the ABS noise are strongly dependent on the relative state of polarization(SOP) of the pump and probe signals.The closer the relative SOP of the pump and probe signals is, the more obvious ABS noise suppression effect will be brought by increasing the power of the input probe signal.
基金Supported by the National High-Tech Research and Development Program of China(No.2009AA03Z401)the National Natural Science Foundation of China(Nos.61077002, 60807030)the Project of National Lab for Tsinghua Information Tech-nologies, China
文摘The authors investigated size-dependent amplified spontaneous emission(ASE) from organic crystals. Specifically, N-(4-{4-[4-(diphenylamino)styryl]styryl}phenyl)-N-phenylbenzene amine(Ph-TPA2) organic crystals were used in the experiment. The ASE threshold was decreased with the decrease of the width of the crystal at the same gain length, which reflects that total internal reflection plays an important role on the ASE properties in these slab organic crystals. The ASE properties pumped by one- and two-photon were also comparatively studied. We found that the thresholds of ASE in two-photon pumping condition are less size-dependent than those in singlephoton condition because of the nonlinear light generation processes in two-photon absorption processes.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.60978061,60777026,60677007 and 60825407)the Program for New Century Excellent Talents in University of China(Grant No.NCET-08-0717)+1 种基金the Beijing Municipal Science and Technology Commission of China(Grant Nos.Z090803044009001 and 4102046)the Program of Introducing Talents of Discipline to Universities,China(Grant No.B08002)
文摘In this work, performance enhancements of amplified spontaneous emission (ASE) from poly[2-methoxy-5-(2'- ethyl-hexyloxy)-l,4-phenylene vinylene] (MEH-PPV) have been achieved via solvent vapour treatment. Correlations between the morphology of the film and the optical performance of polymer-based ASE are investigated. The active layers are characterised by atomic force microscopy and optical absorption. The results show that the solvent-vapour treatment can induce the MEH-PPV self-organisation into an ordered structure with a smooth surface, leading to enhanced optical gain. Thus the solvent-vapour treatment is a good method for improving the optical properties of the MEH-PPV.
基金Project supported by the National Natural Science Foundation of China (Grant Nos.60978061,60777026,60677007,and 60825407)the Program for New Century Excellent Talents in University of China (Grant No.NCET-08-0717)+1 种基金the Beijing Municipal Science and Technology Commission of China (Grant Nos.Z090803044009001 and 4102046)the Program of Introducing Talents of Discipline to Universities,China (Grant No.B08002)
文摘We investigate the amplified spontaneous emission (ASE) from an Ag-backed poly[2-methoxy-5-(2'-ethylhexyloxy)- 1,4-phenylenevinylene] (MEH-PPV) film with different film thicknesses. The ASE characteristics of Ag-backed MEH- PPV films with different thicknesses show that increasing the film thickness can reduce the influence of the Ag cladding. The threshold, the gain, and the loss of the device with a thickness of 170 nm are comparable to those of a metal-free device. The lasing threshold of this device is about 7.5 times that of a metal-free device. Our findings demonstrate that Ag-backed MEH-PPV film with an appropriate thickness can still be a good polymer gain material for the fabrication of solid-state lasers.