The objective of the present study was to gain better insight into the physiological mechanisms on the effects of copper (Cu) on photosynthesis and active oxygen metabolism in three-colored amaranth plant (Amaranth...The objective of the present study was to gain better insight into the physiological mechanisms on the effects of copper (Cu) on photosynthesis and active oxygen metabolism in three-colored amaranth plant (Amaranthus tricolor). Three- colored amaranth seedlings were subjected to different Cu levels in soils during the entire experimental period. The parameters of growth, photosynthesis, mineral elements contents, and active oxygen metabolism were investigated using plant physiological methods. The results showed that 2.0 and 4.0 mmol Cu kg^-1 treatments decreased the whole plant biomass to 91 and 73% of the control, respectively. The net photosynthetic rate (Pn) and the stomatal conductance (gs) were similarly reduced in the third leaves of three-colored amaranth seedlings treated with 2.0 and 4.0 mmol Cu kg^-1 soil, respectively. None of the investigated Cu levels decreased the internal CO2 concentration (Ci). The effect of Cu on the potential efficiency of photosystem Ⅱ (Fv/Fm) was negligible, whereas the effect of Cu on the PS Ⅱ quantum efficiency (ΦPS Ⅱ) after plant adaptation in actinic irradiation was more noticeable. On the other hand, decreases in water percentage, contents of photosynthetic pigments and mineral elements including Fe, K, and Mg, and significant increase in the Cu content were observed in the third leaves of Cu-treated plants. Superoxide dismutase (SOD) and peroxidase (POD) activities as well as the proline (Pro) content significantly increased in the third leaves of the three-colored amaranth seedlings treated with 2.0 and 4.0 mmol Cu kg^-1 soil, while catalase (CAT) and ascorbate peroxidase (APX) activities as well as the contents of carotenoid (Car), glutathione (GSH), and ascorbic acid (AsA) decreased, and accompanied by the increases in the contents of hydrogen peroxide (H2O2), superoxide anion (O2^-), and malondialdehyde (MDA), and electrolyte leakage. As a result of the imbalance of active oxygen metabolism, Pn and ΦPS Ⅱ decreased, and peroxidization enhanced under levels of 2.0 and 4.0 mmol Cu kg^-1 soil. Finally, the growth of three-colored amaranth plant was significantly inhibited.展开更多
Four new bisabolane sesquiterpenoids daedatrins A-D(1-4),a cadinane sesquiterpene 12-hydroxy-α-cadinol(5),and a heptanorergosterane derivative daedatrin G(6)were isolated from cultures of the basidiomycete Daedaleops...Four new bisabolane sesquiterpenoids daedatrins A-D(1-4),a cadinane sesquiterpene 12-hydroxy-α-cadinol(5),and a heptanorergosterane derivative daedatrin G(6)were isolated from cultures of the basidiomycete Daedaleopsis tricolor.Their structures were elucidated by spectroscopic methods including extensive 2D NMR techniques and X-ray crystallography.All the compounds showed no significant activity against five human cancer cell lines.展开更多
Plants synthesize the osmoprotectant glycine betaine (GB) via choline→betaine aldehyde→glycine be- taine[1]. Two enzymes are involved in the pathway choline monooxygenase (CMO) and betaine aldehyde dehydrogenase (BA...Plants synthesize the osmoprotectant glycine betaine (GB) via choline→betaine aldehyde→glycine be- taine[1]. Two enzymes are involved in the pathway choline monooxygenase (CMO) and betaine aldehyde dehydrogenase (BADH). A full length CMO cDNA (1,643bp) was cloned from Amaranthus tricolor. The open reading frame encoded a 442-amino acid polypeptide, which showed 69% identity with CMOs in Spina- cia oleracea L. and Beta vulgaris L. DNA gel blot analysis indicated the presence of one copy of CMO gene in the A. tricolor genome. The expressions of CMO and BADH proteins in A.tricolor leaves significantly increased under salinization, drought and heat stress (42℃), as determined by immunoblot analysis, but did not respond to cold stress (4℃), or exogenous ABA application. The increase of GB content in leaves was parallel to CMO and BADH contents.展开更多
The red, green and blue (R/G/B) tricolor emitting phosphors Ba2ZnSi2O7 co-doped with Ce3+and Eu3+were synthesized in air atmosphere by a conventional high temperature solid-state reaction technique. All of the exc...The red, green and blue (R/G/B) tricolor emitting phosphors Ba2ZnSi2O7 co-doped with Ce3+and Eu3+were synthesized in air atmosphere by a conventional high temperature solid-state reaction technique. All of the excitation spectrum of the phosphor Ba2ZnSi2O7:Ce,Eu showed a strong broad band absorption in the n-UV region whenever monitored by red (630 nm)-emitting or by green (500 nm)-and blue (402 nm)-emitting. Under the excitation of 330 nm, the emission spectrum containing a blue-violet emis-sion band, a green emission and four sharp lines originated from the characteristic transitions of Ce3+, Eu2+and Eu3+ions, of which the relative intensities of the three emission bands could be controlled by the doping concentration of Ce3+. The ca. CIE chromaticity co-ordinates (x=0.317, y=0.309) of the phosphor Ba1.94ZnSi2O7:0.03Eu,0.01Ce was very close to the standard white (x=0.33, y=0.33), which suggested that it was a novel single-phased white-light emitting phosphor for LED-based near-UV chip. The mechanisms of energy transfer from Eu2+to Eu3+via Ce3+was also discussed.展开更多
We propose and experimentally demonstrate a recorded 1-m bidirectional 20.231-Gbit/s tricolor R/G/B laser diode(LD) based visible-light communication(VLC) system supporting signal remodulation. In the signal remodulat...We propose and experimentally demonstrate a recorded 1-m bidirectional 20.231-Gbit/s tricolor R/G/B laser diode(LD) based visible-light communication(VLC) system supporting signal remodulation. In the signal remodulation system, an LD source is not needed at the client side. The client reuses the downstream signal sent from the central office(CO) and remodulates it to produce the upstream signal. As the LD sources are located at the CO, the laser wavelength and temperature managements at the cost-sensitive client side are not needed.This is the first demonstration, to our knowledge, of a >20 Gbit∕s data rate tricolor R/G/B VLC signal transmission supporting upstream remodulation.展开更多
A method of color image single-channel encryption is proposed. The proposed method uses tricolor grating to encode a color image into a gray level image, then the gray level image is encrypted by double random phase e...A method of color image single-channel encryption is proposed. The proposed method uses tricolor grating to encode a color image into a gray level image, then the gray level image is encrypted by double random phase encryption, so a color image is encrypted in a single-channel and its security is ensured. Computer simulations and the chromatic aberration analysis are given to prove the possibility of the proposed idea.The optical system is simpler and is easy to be applied into practice. The simulation results show that this method is efficiency to encrypt a color image, and it is robust.展开更多
A P^+-nc-Si:H film(boron-doped nc-Si:H thin film) was used as a complex anode of an OLED.As an ideal candidate for the composite anode,the P^+-nc-Si:H thin film has a good conductivity with a high work function...A P^+-nc-Si:H film(boron-doped nc-Si:H thin film) was used as a complex anode of an OLED.As an ideal candidate for the composite anode,the P^+-nc-Si:H thin film has a good conductivity with a high work function(- 5.7 eV) and outstanding optical properties of high reflectivity,transmission,and a very low absorption.As a result,the combination of the relatively high reflectivity of a P^+-nc-Si:H film/ITO complex anode with the very high reflectivity of an Al cathode could form a micro-cavity structure with a certain Q to improve the efficiency of the OLED fabricated on it.An RGB pixel generated by microcavity OLEDs is beneficial for both the reduction of the light loss and the improvement of the color purity and the efficiency.The small molecule Alq would be useful for the emitting light layer(EML) of the MOLED,and the P^+-nc-Si film would be used as a complex anode of the MOLED,whose configuration can be constructed as Glass/LTO/P^+-nc-Si:H/ITO/MoO3/NPB/Alq/LiF/Al.By adjusting the thickness of the organic layer NPB/Alq,the optical length of the microcavity and the REB colors of the device can be obtained.The peak wavelengths of an OLED are located at 486,550,and 608 nm,respectively.The CIE coordinates are(0.21,0.45),(0.33,0.63),and(0.54,0.54),and the full widths at half maximum(FWHM) are 35,32,and 39 nm for red,green,and blue,respectively.展开更多
Ⅰ. INTRODUCTIONThe valuable information about the ancient ceramics can be acquired from studying their structures, compositions and manufacture technology by modern scientific and technical method. It is an important...Ⅰ. INTRODUCTIONThe valuable information about the ancient ceramics can be acquired from studying their structures, compositions and manufacture technology by modern scientific and technical method. It is an important field of the modern scientific and technological archaeology (STA), which is also called experimental archaeology and has a special significance for the "country of ceramics" .展开更多
A Eu, Dy co-doped SiO2 matrix, white emitting phosphor was prepared by the sol-gel technique. Strong red, green and blue emissions located at 618 nm, 573 nm and 400-550 nm were observed under UV laser excitation at ro...A Eu, Dy co-doped SiO2 matrix, white emitting phosphor was prepared by the sol-gel technique. Strong red, green and blue emissions located at 618 nm, 573 nm and 400-550 nm were observed under UV laser excitation at room temperature. Such techniques as FT-IR and TGA-DSC were used to measure the microstructure of the luminescent material. The influence of the preparation techniques on the luminescence property of the Eu, Dy co-doped SiO2 matrix, such as anneal temperature, anneal time, dried atmosphere and the components of the matrix, was systematically studied, and the luminescence mechanism was interpreted. The red emission is the strongest when annealed at 750 ℃ . However, blue emission appears when annealed at 700 ℃ and is the intensest at 900℃ . For the samples dried in vacuum, Eu3+ is more easily deoxidized to Eu2+ at lower temperatures, because the samples dried in the air compared with that dried in vacuum need higher temperature to form network structures. Only the SA and SAB matrix annealed at 850 ℃ had blue emission in the four matrices (SA, SAB, SB, S) xerogel and the emission in the SAB matrix was stronger than that in the SA matrix. This may be due to the eutectic phase formed by the oxide boron, alkaline oxide and alumina in the SAB matrix, which constructs network structures and stabilizes the emission center and enhances the blue emission.展开更多
基金the Natural Science Foundation of Zhejiang Province, China (Y504256).
文摘The objective of the present study was to gain better insight into the physiological mechanisms on the effects of copper (Cu) on photosynthesis and active oxygen metabolism in three-colored amaranth plant (Amaranthus tricolor). Three- colored amaranth seedlings were subjected to different Cu levels in soils during the entire experimental period. The parameters of growth, photosynthesis, mineral elements contents, and active oxygen metabolism were investigated using plant physiological methods. The results showed that 2.0 and 4.0 mmol Cu kg^-1 treatments decreased the whole plant biomass to 91 and 73% of the control, respectively. The net photosynthetic rate (Pn) and the stomatal conductance (gs) were similarly reduced in the third leaves of three-colored amaranth seedlings treated with 2.0 and 4.0 mmol Cu kg^-1 soil, respectively. None of the investigated Cu levels decreased the internal CO2 concentration (Ci). The effect of Cu on the potential efficiency of photosystem Ⅱ (Fv/Fm) was negligible, whereas the effect of Cu on the PS Ⅱ quantum efficiency (ΦPS Ⅱ) after plant adaptation in actinic irradiation was more noticeable. On the other hand, decreases in water percentage, contents of photosynthetic pigments and mineral elements including Fe, K, and Mg, and significant increase in the Cu content were observed in the third leaves of Cu-treated plants. Superoxide dismutase (SOD) and peroxidase (POD) activities as well as the proline (Pro) content significantly increased in the third leaves of the three-colored amaranth seedlings treated with 2.0 and 4.0 mmol Cu kg^-1 soil, while catalase (CAT) and ascorbate peroxidase (APX) activities as well as the contents of carotenoid (Car), glutathione (GSH), and ascorbic acid (AsA) decreased, and accompanied by the increases in the contents of hydrogen peroxide (H2O2), superoxide anion (O2^-), and malondialdehyde (MDA), and electrolyte leakage. As a result of the imbalance of active oxygen metabolism, Pn and ΦPS Ⅱ decreased, and peroxidization enhanced under levels of 2.0 and 4.0 mmol Cu kg^-1 soil. Finally, the growth of three-colored amaranth plant was significantly inhibited.
基金This work was financially supported by the National Natural Science Foundation of China(U1132607).
文摘Four new bisabolane sesquiterpenoids daedatrins A-D(1-4),a cadinane sesquiterpene 12-hydroxy-α-cadinol(5),and a heptanorergosterane derivative daedatrin G(6)were isolated from cultures of the basidiomycete Daedaleopsis tricolor.Their structures were elucidated by spectroscopic methods including extensive 2D NMR techniques and X-ray crystallography.All the compounds showed no significant activity against five human cancer cell lines.
文摘Plants synthesize the osmoprotectant glycine betaine (GB) via choline→betaine aldehyde→glycine be- taine[1]. Two enzymes are involved in the pathway choline monooxygenase (CMO) and betaine aldehyde dehydrogenase (BADH). A full length CMO cDNA (1,643bp) was cloned from Amaranthus tricolor. The open reading frame encoded a 442-amino acid polypeptide, which showed 69% identity with CMOs in Spina- cia oleracea L. and Beta vulgaris L. DNA gel blot analysis indicated the presence of one copy of CMO gene in the A. tricolor genome. The expressions of CMO and BADH proteins in A.tricolor leaves significantly increased under salinization, drought and heat stress (42℃), as determined by immunoblot analysis, but did not respond to cold stress (4℃), or exogenous ABA application. The increase of GB content in leaves was parallel to CMO and BADH contents.
基金Project supported by the National Natural Science Foundation of China(20971042)Specialized Research Fund for the Doctoral Program of Higher Education(20124306120005,20134306120009)+2 种基金Hunan Provincial Natural Science Foundation of China(2015JJ2100)Scientific Research Fund of Hunan Provincial Education Department(13C012)Aid Program for Science and Technology Innovative Research Team in Higher Educational Institutions of Hunan Province
文摘The red, green and blue (R/G/B) tricolor emitting phosphors Ba2ZnSi2O7 co-doped with Ce3+and Eu3+were synthesized in air atmosphere by a conventional high temperature solid-state reaction technique. All of the excitation spectrum of the phosphor Ba2ZnSi2O7:Ce,Eu showed a strong broad band absorption in the n-UV region whenever monitored by red (630 nm)-emitting or by green (500 nm)-and blue (402 nm)-emitting. Under the excitation of 330 nm, the emission spectrum containing a blue-violet emis-sion band, a green emission and four sharp lines originated from the characteristic transitions of Ce3+, Eu2+and Eu3+ions, of which the relative intensities of the three emission bands could be controlled by the doping concentration of Ce3+. The ca. CIE chromaticity co-ordinates (x=0.317, y=0.309) of the phosphor Ba1.94ZnSi2O7:0.03Eu,0.01Ce was very close to the standard white (x=0.33, y=0.33), which suggested that it was a novel single-phased white-light emitting phosphor for LED-based near-UV chip. The mechanisms of energy transfer from Eu2+to Eu3+via Ce3+was also discussed.
基金Ministry of Science and Technology,Taiwan(MOST)(MOST-106-2221-E-009-105-MY3)Aim for the Top University PlanMinistry of Education(MOE),Taiwan,China
文摘We propose and experimentally demonstrate a recorded 1-m bidirectional 20.231-Gbit/s tricolor R/G/B laser diode(LD) based visible-light communication(VLC) system supporting signal remodulation. In the signal remodulation system, an LD source is not needed at the client side. The client reuses the downstream signal sent from the central office(CO) and remodulates it to produce the upstream signal. As the LD sources are located at the CO, the laser wavelength and temperature managements at the cost-sensitive client side are not needed.This is the first demonstration, to our knowledge, of a >20 Gbit∕s data rate tricolor R/G/B VLC signal transmission supporting upstream remodulation.
基金supported by the Opening Subject of KeyLaboratory of Opoelectronic Information Science & Technology,Ministry of Education of China(Grant No. 2005-141)
文摘A method of color image single-channel encryption is proposed. The proposed method uses tricolor grating to encode a color image into a gray level image, then the gray level image is encrypted by double random phase encryption, so a color image is encrypted in a single-channel and its security is ensured. Computer simulations and the chromatic aberration analysis are given to prove the possibility of the proposed idea.The optical system is simpler and is easy to be applied into practice. The simulation results show that this method is efficiency to encrypt a color image, and it is robust.
基金supported by the National High Technology Research and Development Program of China(No.2004AA303570)the National Natural Science Foundation of China (No. 60437030)
文摘A P^+-nc-Si:H film(boron-doped nc-Si:H thin film) was used as a complex anode of an OLED.As an ideal candidate for the composite anode,the P^+-nc-Si:H thin film has a good conductivity with a high work function(- 5.7 eV) and outstanding optical properties of high reflectivity,transmission,and a very low absorption.As a result,the combination of the relatively high reflectivity of a P^+-nc-Si:H film/ITO complex anode with the very high reflectivity of an Al cathode could form a micro-cavity structure with a certain Q to improve the efficiency of the OLED fabricated on it.An RGB pixel generated by microcavity OLEDs is beneficial for both the reduction of the light loss and the improvement of the color purity and the efficiency.The small molecule Alq would be useful for the emitting light layer(EML) of the MOLED,and the P^+-nc-Si film would be used as a complex anode of the MOLED,whose configuration can be constructed as Glass/LTO/P^+-nc-Si:H/ITO/MoO3/NPB/Alq/LiF/Al.By adjusting the thickness of the organic layer NPB/Alq,the optical length of the microcavity and the REB colors of the device can be obtained.The peak wavelengths of an OLED are located at 486,550,and 608 nm,respectively.The CIE coordinates are(0.21,0.45),(0.33,0.63),and(0.54,0.54),and the full widths at half maximum(FWHM) are 35,32,and 39 nm for red,green,and blue,respectively.
文摘Ⅰ. INTRODUCTIONThe valuable information about the ancient ceramics can be acquired from studying their structures, compositions and manufacture technology by modern scientific and technical method. It is an important field of the modern scientific and technological archaeology (STA), which is also called experimental archaeology and has a special significance for the "country of ceramics" .
基金the National Natural Science Foundation of China (Grant No. 20876125)the Technology Research Project of Higher Education Office in Shaanxi Province (Grant No. 08JK451)
文摘A Eu, Dy co-doped SiO2 matrix, white emitting phosphor was prepared by the sol-gel technique. Strong red, green and blue emissions located at 618 nm, 573 nm and 400-550 nm were observed under UV laser excitation at room temperature. Such techniques as FT-IR and TGA-DSC were used to measure the microstructure of the luminescent material. The influence of the preparation techniques on the luminescence property of the Eu, Dy co-doped SiO2 matrix, such as anneal temperature, anneal time, dried atmosphere and the components of the matrix, was systematically studied, and the luminescence mechanism was interpreted. The red emission is the strongest when annealed at 750 ℃ . However, blue emission appears when annealed at 700 ℃ and is the intensest at 900℃ . For the samples dried in vacuum, Eu3+ is more easily deoxidized to Eu2+ at lower temperatures, because the samples dried in the air compared with that dried in vacuum need higher temperature to form network structures. Only the SA and SAB matrix annealed at 850 ℃ had blue emission in the four matrices (SA, SAB, SB, S) xerogel and the emission in the SAB matrix was stronger than that in the SA matrix. This may be due to the eutectic phase formed by the oxide boron, alkaline oxide and alumina in the SAB matrix, which constructs network structures and stabilizes the emission center and enhances the blue emission.