Visible and near-infrared photodetectors are widely used in intelligent driving,health monitoring,and other fields.However,the application of photodetectors in the near-infrared region is significantly impacted by hig...Visible and near-infrared photodetectors are widely used in intelligent driving,health monitoring,and other fields.However,the application of photodetectors in the near-infrared region is significantly impacted by high dark current,which can greatly reduce their performance and sensitivity,thereby limiting their effectiveness in certain applications.In this work,the introduction of a C60 back interface layer successfully mitigated back interface reactions to decrease the thickness of the Mo(S,Se)_(2)layer,tailoring the back-contact barrier and preventing reverse charge injection,resulting in a kesterite photodetector with an ultralow dark current density of 5.2×10^(-9)mA/cm^(2)and ultra-weak-light detection at levels as low as 25 pW/cm^(2).Besides,under a self-powered operation,it demonstrates outstanding performance,achieving a peak responsivity of 0.68 A/W,a wide response range spanning from 300 to 1600 nm,and an impressive detectivity of 5.27×10^(14)Jones.In addition,it offers exceptionally rapid response times,with rise and decay times of 70 and 650 ns,respectively.This research offers important insights for developing high-performance self-powered near-infrared photodetectors that have high responsivity,rapid response times,and ultralow dark current.展开更多
The effect of weak light on the peroxidation of membrane_lipid of one_year_old cherries ( Prunus pseudocerasus L. 'Laiyang') was studied by whole_tree shading. The results showed that the net photosynthetic...The effect of weak light on the peroxidation of membrane_lipid of one_year_old cherries ( Prunus pseudocerasus L. 'Laiyang') was studied by whole_tree shading. The results showed that the net photosynthetic rate of cherry leaves under weak light was remarkably lower; the activity peroxidase (POD) increased when light intensity decreased; the activity of catalase (CAT) showed an opposite trend, and it was positively correlated with light intensity; the activity of superoxide dismutase (SOD) increased under 366 μmol·m -2 ·s -1 and 533.8 μmol·m -2 ·s -1 light intensity, but decreased under 228.8 μmol·m -2 ·s -1 and 83.9 μmol·m -2 ·s -1 light intensity. A remarkable increase of malondialdehyde (MDA), a product of membrane_lipid peroxidation, was also observed in cherry leaves when treated with weak light, indicating more serious peroxidation in the membrane.展开更多
Leaves from three_year_old solar greenhouse nectarine trees ( Prunus persica L. var. nectarina Ait. “Zao Hong Yan”) were used as materials in this study. It was the first time that the ultrastructural charact...Leaves from three_year_old solar greenhouse nectarine trees ( Prunus persica L. var. nectarina Ait. “Zao Hong Yan”) were used as materials in this study. It was the first time that the ultrastructural characteristics of phloem tissues of source leaves were observed and compared in normal and weak light intensities using the transmission electron microscopy. Results showed that the average diameters of companion cells (CC) and sieve elements (SE) of all kinds of veins were bigger in normal than that in weak light intensity, indicating that light could influence the cell development and growth. Dense cytoplasm with abundant mitochondria, endoplasmic reticulums, multivesicular bodies, vesicles and plastids were observed in normal light intensity. On the contrary, CC with small vacuolar structures and few mitochondrias, endoplasmic reticulums were shown in weak light. Misalignment of grana thylakoid margins of nectarine leaves also was seen in weak light. The sieve pores of SEs were obstructed in weak light. Chloroplasts with numerous starch grains and few mitochondrias were noticed in the mesophyll cell (MES) surrounding the bundle sheath in weak light. The storage of starch grains appeared to result from an unbalance between photosynthate production and export of photosynthates. This observation provided a strong support to the point that most leaves export the most of assimilates in the light time. Plasmodesmal densities between SE/CC, CC/PP (phloem parenchyma cell), PP/PP and PP/BSC (bundle_sheath cell) decreased in weak light. Plasmodesmata were observed between CC/SE (NS) (nacreous_walled sieve element), PP/BSC in branch veins in normal light intensity, but not in weak light. Thus apoplasmic pathway may be the main mode of transport of assimilates in weak light, however symplasmic pathway may be the main mode of transport of assimilates in normal light intensity. These results demonstrated that the solar greenhouse nectarine trees could be adapted to the weak light via the ultrastructure variation of phloem tissues of the source leaves.展开更多
Dynamic changes of starch, amylose, sucrose contents and the activities of starch synthesis enzymes under shading treatments alter flowering were studied using two rice varieties IR72 (indica) and Nipponbare (japon...Dynamic changes of starch, amylose, sucrose contents and the activities of starch synthesis enzymes under shading treatments alter flowering were studied using two rice varieties IR72 (indica) and Nipponbare (japonica) as materials. Under shading treatments, the starch, amylose and sucrose contents decreased, while ADP-glucose pyrophosphorylase (ADPGPPase) activity only changed a little, soluble starch synthase activity and granule bound starch synthase activity decreased, soluble starch branching enzyme (SSBE, Q-enzyme) activity and granule bound starch branching enzyme (GBSBE, Q-enzyme) activity increased, and starch debranching enzyme (DBE, R-enzyme) activity varied with varieties. Correlation analyses showed that the changes of starch content were positively and significantly correlated with the changes of sucrose content in the weak light. Both ADPGPPase activity and SSBE activity were positively and significantly correlated with starch accumulation rate. It was implied that the decline of starch synthase activities was related to the decrease of starch content and the increase of the activity of starch branching enzyme played an important role in the decrease of the ratio of amylose to the total starch under the weak light.展开更多
Anthocyanidin in plants, an important pigment, is of great interest to researchers, consumers, and commercial entities due to its physiological functions. Anthocyanin content and mRNA levels of anthocynin biosynthesis...Anthocyanidin in plants, an important pigment, is of great interest to researchers, consumers, and commercial entities due to its physiological functions. Anthocyanin content and mRNA levels of anthocynin biosynthesis genes were investigated in storage root of different purple-fleshed sweet potatoes (PFSP) genotypes to understand the regulation mechanism of anthocyanin under weak light conditions. Anthocyanin content, its amount of accumulation, and the expression of CHS, DFR, F3H, GT, and ANS genes in the PFSP storage root under weak light conditions were studied. The results demonstrated that the anthocyanin content of the treatments was decreased and was obviously lower than that of the control until 30 days after shading in Ayamurasaki, while it was lower than that of the control from the beginning of shading in Jishu 18. Their accumulation rates of both treatmeants were lower than its control before 10-20 d of shading in Jishu 18, while those of Ayamurasaki weren't in their treatments. This indicated that Jishul 8 is more sensitive to light as compared to Ayamuraska. Under the different weak light conditions, mRNA levels for ibCHS, ibF3H, ibDFR, and ibANS were obviously decreased, while the expression of ibGT was increased. These results indicated that anthocyanin content was regulated by light at the mRNA levels and the enzymatic level in sweet potato. Therefore, the development dynamic response to anthocyanin content varied in different genotypes of PFSP, and mRNA levels of anthocyanin biosynthesis were inhibited under the weak light condition.展开更多
The effect of weak light on the photoassimilates distribution and transformation of young Jingyu grape plants ( Vitis vinefera L. cv. Jingyu) were studied by shading. Compared to the grape grown under natural light in...The effect of weak light on the photoassimilates distribution and transformation of young Jingyu grape plants ( Vitis vinefera L. cv. Jingyu) were studied by shading. Compared to the grape grown under natural light intensity environment, the net photosynthetic rate diurnal variation curve of experimental plants grown in weak light intensity environment was remarkably lower. Its leaf and stem biomass ratio increased when light intensity decreased, the root and new shoot biomass ratio showed an opposite trend. The 14 C-photoassimilates was mostly distributed to young leaves and stem, a little was distributed to root. The metabolism of 14C-photoassimilates distributed to the entire grape body were also changed under weak light intensity environment.展开更多
By using semiclassical theory combined with multiple-scale method, we analytically study the linear absorption and the nonlinear dynamical properties in a lifetime broadened Λ-type three-level self-assembled quantum ...By using semiclassical theory combined with multiple-scale method, we analytically study the linear absorption and the nonlinear dynamical properties in a lifetime broadened Λ-type three-level self-assembled quantum dots. It is found that this system can exhibit the transparency, and the width of the transparency window becomes wider with the increase of control light field. Interestingly, a weak probe light beam can form spatial weak-light dark solitons. When it propagates along the axial direction, the soliton will transform into a steady spatial weak-light ring dark soltion. In addition, the stability of two-dimensional spatial optical solitons is testified numerically.展开更多
Potted seedlings of Hedera nepalensis and H. helix were exposed to formaldehyde and low light alone or in combination for four months, before the morphological and nutritive indices of the plants were measured to asse...Potted seedlings of Hedera nepalensis and H. helix were exposed to formaldehyde and low light alone or in combination for four months, before the morphological and nutritive indices of the plants were measured to assess the effects of formaldehyde and low-light stress on the growth and nutrient accumulation of Hedera species. The results showed that treatment with either formaldehyde or low-light stress reduced leaf length, leaf width, stem length, stem diameter, root length and biomass, but increased leaf shape index of the two Hedera species. Treatment with formaldehyde alone increased root-shoot ratio, while treatment with formaldehyde + low light or low light alone decreased root-shoot ratio of the two Hedera species. Under the stress of formaldehyde, soluble sugar content decreased, while starch content increased in roots, stems and leaves of the two Hedera species; total carbon content, proline content and carbon-to-nitrogen (C/N) ratio increased, while protein content and phosphorus content decreased in roots of the two Hedera species; the contents of total carbon, protein and total nitrogen in leaves of the two Hedera species; C/N ratio in roots of H. nepalensis increased; the C/N ratio in roots of H. nepalensis and that in leaves of the two Hedera species significantly increased. Under formaldehyde + low light stress, the soluble sugar content decreased, while starch content increased in stems and leaves of the two Hedera species; starch content in roots of the two Hedera species decreased; the contents of protein and total nitrogen decreased, while C/N ratio increased in leaves of H. nepalensis ; proline content in roots and stems of the two Hedera species significantly increased.展开更多
基金supported by the National Natural Science Foundation of China(No.52472225)the Science and Technology Plan Project of Shenzhen(No.20220808165025003),China。
文摘Visible and near-infrared photodetectors are widely used in intelligent driving,health monitoring,and other fields.However,the application of photodetectors in the near-infrared region is significantly impacted by high dark current,which can greatly reduce their performance and sensitivity,thereby limiting their effectiveness in certain applications.In this work,the introduction of a C60 back interface layer successfully mitigated back interface reactions to decrease the thickness of the Mo(S,Se)_(2)layer,tailoring the back-contact barrier and preventing reverse charge injection,resulting in a kesterite photodetector with an ultralow dark current density of 5.2×10^(-9)mA/cm^(2)and ultra-weak-light detection at levels as low as 25 pW/cm^(2).Besides,under a self-powered operation,it demonstrates outstanding performance,achieving a peak responsivity of 0.68 A/W,a wide response range spanning from 300 to 1600 nm,and an impressive detectivity of 5.27×10^(14)Jones.In addition,it offers exceptionally rapid response times,with rise and decay times of 70 and 650 ns,respectively.This research offers important insights for developing high-performance self-powered near-infrared photodetectors that have high responsivity,rapid response times,and ultralow dark current.
文摘The effect of weak light on the peroxidation of membrane_lipid of one_year_old cherries ( Prunus pseudocerasus L. 'Laiyang') was studied by whole_tree shading. The results showed that the net photosynthetic rate of cherry leaves under weak light was remarkably lower; the activity peroxidase (POD) increased when light intensity decreased; the activity of catalase (CAT) showed an opposite trend, and it was positively correlated with light intensity; the activity of superoxide dismutase (SOD) increased under 366 μmol·m -2 ·s -1 and 533.8 μmol·m -2 ·s -1 light intensity, but decreased under 228.8 μmol·m -2 ·s -1 and 83.9 μmol·m -2 ·s -1 light intensity. A remarkable increase of malondialdehyde (MDA), a product of membrane_lipid peroxidation, was also observed in cherry leaves when treated with weak light, indicating more serious peroxidation in the membrane.
文摘Leaves from three_year_old solar greenhouse nectarine trees ( Prunus persica L. var. nectarina Ait. “Zao Hong Yan”) were used as materials in this study. It was the first time that the ultrastructural characteristics of phloem tissues of source leaves were observed and compared in normal and weak light intensities using the transmission electron microscopy. Results showed that the average diameters of companion cells (CC) and sieve elements (SE) of all kinds of veins were bigger in normal than that in weak light intensity, indicating that light could influence the cell development and growth. Dense cytoplasm with abundant mitochondria, endoplasmic reticulums, multivesicular bodies, vesicles and plastids were observed in normal light intensity. On the contrary, CC with small vacuolar structures and few mitochondrias, endoplasmic reticulums were shown in weak light. Misalignment of grana thylakoid margins of nectarine leaves also was seen in weak light. The sieve pores of SEs were obstructed in weak light. Chloroplasts with numerous starch grains and few mitochondrias were noticed in the mesophyll cell (MES) surrounding the bundle sheath in weak light. The storage of starch grains appeared to result from an unbalance between photosynthate production and export of photosynthates. This observation provided a strong support to the point that most leaves export the most of assimilates in the light time. Plasmodesmal densities between SE/CC, CC/PP (phloem parenchyma cell), PP/PP and PP/BSC (bundle_sheath cell) decreased in weak light. Plasmodesmata were observed between CC/SE (NS) (nacreous_walled sieve element), PP/BSC in branch veins in normal light intensity, but not in weak light. Thus apoplasmic pathway may be the main mode of transport of assimilates in weak light, however symplasmic pathway may be the main mode of transport of assimilates in normal light intensity. These results demonstrated that the solar greenhouse nectarine trees could be adapted to the weak light via the ultrastructure variation of phloem tissues of the source leaves.
文摘Dynamic changes of starch, amylose, sucrose contents and the activities of starch synthesis enzymes under shading treatments alter flowering were studied using two rice varieties IR72 (indica) and Nipponbare (japonica) as materials. Under shading treatments, the starch, amylose and sucrose contents decreased, while ADP-glucose pyrophosphorylase (ADPGPPase) activity only changed a little, soluble starch synthase activity and granule bound starch synthase activity decreased, soluble starch branching enzyme (SSBE, Q-enzyme) activity and granule bound starch branching enzyme (GBSBE, Q-enzyme) activity increased, and starch debranching enzyme (DBE, R-enzyme) activity varied with varieties. Correlation analyses showed that the changes of starch content were positively and significantly correlated with the changes of sucrose content in the weak light. Both ADPGPPase activity and SSBE activity were positively and significantly correlated with starch accumulation rate. It was implied that the decline of starch synthase activities was related to the decrease of starch content and the increase of the activity of starch branching enzyme played an important role in the decrease of the ratio of amylose to the total starch under the weak light.
基金support by the NationalHigh-Tech R&D Program of China (863 Program,2006AA100107)the National Key Technologies R&DProgram of China (2006BAD01A06-2)+2 种基金the NationalSpecial Scientific Research Project for Public Industryof China (nyhyzx07-012-03)the Project of 948 from Ministry of Agriculture of China (2006-G21-02)the National System of Sweet Potato Industrial Tech-nology of China (nycytx-16-B-3)
文摘Anthocyanidin in plants, an important pigment, is of great interest to researchers, consumers, and commercial entities due to its physiological functions. Anthocyanin content and mRNA levels of anthocynin biosynthesis genes were investigated in storage root of different purple-fleshed sweet potatoes (PFSP) genotypes to understand the regulation mechanism of anthocyanin under weak light conditions. Anthocyanin content, its amount of accumulation, and the expression of CHS, DFR, F3H, GT, and ANS genes in the PFSP storage root under weak light conditions were studied. The results demonstrated that the anthocyanin content of the treatments was decreased and was obviously lower than that of the control until 30 days after shading in Ayamurasaki, while it was lower than that of the control from the beginning of shading in Jishu 18. Their accumulation rates of both treatmeants were lower than its control before 10-20 d of shading in Jishu 18, while those of Ayamurasaki weren't in their treatments. This indicated that Jishul 8 is more sensitive to light as compared to Ayamuraska. Under the different weak light conditions, mRNA levels for ibCHS, ibF3H, ibDFR, and ibANS were obviously decreased, while the expression of ibGT was increased. These results indicated that anthocyanin content was regulated by light at the mRNA levels and the enzymatic level in sweet potato. Therefore, the development dynamic response to anthocyanin content varied in different genotypes of PFSP, and mRNA levels of anthocyanin biosynthesis were inhibited under the weak light condition.
基金supported by the National Natural Science Foundation of China(30070531).
文摘The effect of weak light on the photoassimilates distribution and transformation of young Jingyu grape plants ( Vitis vinefera L. cv. Jingyu) were studied by shading. Compared to the grape grown under natural light intensity environment, the net photosynthetic rate diurnal variation curve of experimental plants grown in weak light intensity environment was remarkably lower. Its leaf and stem biomass ratio increased when light intensity decreased, the root and new shoot biomass ratio showed an opposite trend. The 14 C-photoassimilates was mostly distributed to young leaves and stem, a little was distributed to root. The metabolism of 14C-photoassimilates distributed to the entire grape body were also changed under weak light intensity environment.
基金Project supported by the Special Funds of the National Natural Science Foundation of China(Grant No.11247313)
文摘By using semiclassical theory combined with multiple-scale method, we analytically study the linear absorption and the nonlinear dynamical properties in a lifetime broadened Λ-type three-level self-assembled quantum dots. It is found that this system can exhibit the transparency, and the width of the transparency window becomes wider with the increase of control light field. Interestingly, a weak probe light beam can form spatial weak-light dark solitons. When it propagates along the axial direction, the soliton will transform into a steady spatial weak-light ring dark soltion. In addition, the stability of two-dimensional spatial optical solitons is testified numerically.
基金Supported by Applied Basic Research Program of Yunnan Province(2017FD087)National Natural Science Foundation of China(31660559)
文摘Potted seedlings of Hedera nepalensis and H. helix were exposed to formaldehyde and low light alone or in combination for four months, before the morphological and nutritive indices of the plants were measured to assess the effects of formaldehyde and low-light stress on the growth and nutrient accumulation of Hedera species. The results showed that treatment with either formaldehyde or low-light stress reduced leaf length, leaf width, stem length, stem diameter, root length and biomass, but increased leaf shape index of the two Hedera species. Treatment with formaldehyde alone increased root-shoot ratio, while treatment with formaldehyde + low light or low light alone decreased root-shoot ratio of the two Hedera species. Under the stress of formaldehyde, soluble sugar content decreased, while starch content increased in roots, stems and leaves of the two Hedera species; total carbon content, proline content and carbon-to-nitrogen (C/N) ratio increased, while protein content and phosphorus content decreased in roots of the two Hedera species; the contents of total carbon, protein and total nitrogen in leaves of the two Hedera species; C/N ratio in roots of H. nepalensis increased; the C/N ratio in roots of H. nepalensis and that in leaves of the two Hedera species significantly increased. Under formaldehyde + low light stress, the soluble sugar content decreased, while starch content increased in stems and leaves of the two Hedera species; starch content in roots of the two Hedera species decreased; the contents of protein and total nitrogen decreased, while C/N ratio increased in leaves of H. nepalensis ; proline content in roots and stems of the two Hedera species significantly increased.