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Biocompatibility of light responsive materials prepared for accommodative intraocular lenses manufacturing
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作者 Chen-Zi Liu Ming-Hao Sun +2 位作者 Wei Dai Lan-Cao Hao Si-Quan Zhu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第12期2167-2176,共10页
AIM:To investigate the biocompatibility and bacterial adhesion properties of light responsive materials(LRM)and analyze the feasibility and biosafety of employing LRM in the preparation of accommodative intraocular le... AIM:To investigate the biocompatibility and bacterial adhesion properties of light responsive materials(LRM)and analyze the feasibility and biosafety of employing LRM in the preparation of accommodative intraocular lenses(AIOLs).METHODS:Employing fundamental experimental research techniques,LRM with human lens epithelial cells(hLECs)and human retinal pigment epithelium cells(ARPE-19 cells)were co-cultured.Commercially available intraocular lenses(IOLs)were used as controls to perform cell counting kit-8(CCK-8),cell staining under varying light intensities,cell adhesion and bacterial adhesion experiments.RESULTS:LRM exhibited a stronger inhibitory effect on the proliferation of ARPE19 cells than commercially available IOLs when co-cultured with the undiluted extract for 96h(P<0.05).Under other culturing conditions,the effects on the proliferation of hLECs and ARPE-19 cells were not significantly different between the two materials.Under the influence of light irradiation at intensities of 200 and 300 mW/cm^(2),LRM demonstrated a markedly higher inhibitory effect on the survival of hLECs compared to commercially available IOLs(P<0.0001).They also showed a stronger suppressive effect on the survival rate of ARPE-19 cells,with significant differences observed at 200 mW/cm^(2)(P<0.001)and extremely significant differences at 300 mW/cm^(2)(P<0.0001).Additionally,compared to commercially available IOLs,LRM had a higher number of cells adhering to their surface(P<0.05),as well as a significantly greater number of adherent bacterium(P<0.0001).CONCLUSION:LRM,characterized by their excellent non-contact tunable deformability and low cytotoxicity to ocular tissues,show considerable potential for use in the fabrication of AIOLs.These materials demonstrate strong cell adhesion;however,during photothermal conversion processes involving shape deformation under various light intensities,the resultant temperature rise may harm surrounding cells.These factors suggest that while the material plays a positive role in reducing the incidence of posterior capsule opacification(PCO),it also poses potential risks for retinal damage.Additionally,the strong bacterial adhesion of these materials indicates an increased risk of endophthalmitis. 展开更多
关键词 light responsive materials accommodative intraocular lens BIOCOMPATIBILITY bacterial adhesion
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Differences in Light Response Curve and CO_2 Response Curve of Korla Fragrant Pear Trees in Different Training Systems 被引量:2
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作者 江振斌 廖康 +5 位作者 曼苏尔.那斯尔 牛莹莹 庞洪翔 孙琪 徐乐 章世奎 《Agricultural Science & Technology》 CAS 2016年第8期1762-1766,共5页
[Objective] This study was conducted to evaluate three training systems for Korla fragrant pear trees by comparing the characteristic parameters of light response curve and CO2 response curve, and to provide some theo... [Objective] This study was conducted to evaluate three training systems for Korla fragrant pear trees by comparing the characteristic parameters of light response curve and CO2 response curve, and to provide some theoretical basis for improving the pruning techniques of Korla fragrant pear trees. [Method] The light response curve and CO2 response curve of the trees trained to three systems were measured by LI-6400 portable photosynthesis system. The SPAD value was measured using SPAD-502 chlorophyll meter, and specific leaf weight was calculated, to evaluate the effects of the three training systems. [Result] The CO2 response curves of the three training systems were basically in agreement with their light response curves, but there were some differences in their characteristic parameters. Among the three training systems, the maximum net photosynthetic rate, apparent quantum yield and light compensation point of espalier trained trees were the highest, while their light saturation point was the lowest. The CO2 saturation point of delayed-open central leader trained trees and open center trained trees were 1 752 and 1 665 μmol/mol, both of which were much higher than that of espalier trained trees. In addition, the carboxylation efficiency and photorespiration rate of espalier trained trees were both higher than those of delayed-open central leader trained trees and open center trained trees, while the CO2 compensation point of espalier trained trees was the lowest. The leaf SPAD value of espalier trained trees was the largest, followed by that of open center trained trees, and the leaf SPAD value of delayed-open central leader trained trees was the smallest. In addition, the leaf area and specific leaf weight of espalier trained trees were both the highest, followed by those of open center trained trees. [Conclusion] Among the training systems for Korla fragrant pear trees, the espalier training system had better ability to capture light, higher photosynthetic productivity and strongest adaptability to light environment, and open center training system takes the second place. On the contrary, delayed-open central leader training system has the weakest adaptability to light environment, but it can adapt to a higher CO2 concentration. In summary, for the training of Korla fragrant pear trees, espalier training system, which has the highest theoretical yield, is the best among the three training systems, and delayed-open central leader training system is the worst. 展开更多
关键词 Korla fragrant pear Training system light response curve CO2 response curve
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Efect of light response on the photocatalytic activity of BiOClxBr1-x in the removal of Rhodamine B from water 被引量:4
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作者 Xiao-ming Mao Cai-mei Fan 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2013年第11期1089-1096,共8页
BiOClxBr1-x catalysts were synthesized through an alcoholysis method and characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM)... BiOClxBr1-x catalysts were synthesized through an alcoholysis method and characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), and diffuse reflectance spectroscopy (DRS). The as-prepared photocatalysts were found to be tetragonal crystal structure and lamellar plate morphology. Their band gaps were between 3.44 and 2.83 eV. The effect of light response on the photocatalytic activity of BiOClxBrl-x was investigated by degradation of Rhodamine B (RhB). Complete removal of RhB from water was realized under simulated sunlight irradiation for 50 min with BiOC10.5Br0.5. Mechanism studies showed that photo- generated holes and superoxide anion radicals played important roles in RhB photodegradation. The results of chemical oxygen demand (COD) confirmed RhB mineralization. The effect of light response on the activity of BiOClxBr1-x was further investigated under monochromatic light irradiation, and BiOCl0.5Br0.5 catalyst exhibited the highest activity. Furthermore, BiOC10.5Br0.5 exhibited high stability, suggesting its practical application for the removal of RhB pollutant from water. 展开更多
关键词 PHOTOCATALYSTS photocatalytic activity light response DEGRADATION organic pollutants
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One-pot topotactic synthesis of Ti^(3+) self-doped 3D TiO_2 hollow nanoboxes with enhanced visible light response 被引量:2
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作者 Chengjiang Zhang Lijun Tian +3 位作者 Lianqin Chen Xiaofang Li Kangle Lv Kejian Deng 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第8期1373-1383,共11页
Ti^(3+) self-doped anatase three-dimensional(3D) TiO_2 hollow nanoboxes were synthesized via a topological transformation process involving template participation by a facile one-pot hydrothermal treatment with a... Ti^(3+) self-doped anatase three-dimensional(3D) TiO_2 hollow nanoboxes were synthesized via a topological transformation process involving template participation by a facile one-pot hydrothermal treatment with an ethanol solution of zinc powder and TiOF_2. It is worth noting that the 3D TiO_2 hollow nanoboxes are assembled from six single-crystal nanosheets and have dominant exposure of the {001} facets. It is found from EPR spectra that adding zinc powder is an environment-friendly and effective strategy to introduce Ti^(3+) and oxygen vacancy(Ov) into the bulk of 3D hollow nanoboxes rather than the surface, which is responsible for their enhanced visible photocatalytic properties.The photocatalytic activity was evaluated by measuring the formation rate of hydroxide free radicals using 7-hydroxycoumarin as a probe. The sample prepared with zinc/TiOF_2 mass ratio of0.25 exhibited the highest RhB photodegradation activity under visible-light irradiation with a degradation rate of 96%, which is 4.0-times higher than that of pure TiO_2. The results suggest a novel approach to construct in-situ 3D hierarchical TiO_2 hollow nanoboxes doped with Ti^(3+) and Ov without introducing any impurity elements for superior visible-light photocatalytic activity. 展开更多
关键词 Ti3+self‐doped Topological transformation Three‐dimensional hollow nanoboxes Visible light response Photocataly ticactivity
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Measuring Carbon Dioxide Sink of Betung Bamboo (Dendrocallamus asper (Schult f.) Backer ex Heyne) by Sinusoidal Curves Fitting on Its Daily Photosynthesis Light Response 被引量:1
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作者 Effendi Tri Bahtiar Naresworo Nugroho Anne Carolina Aditya Chandra Maulana 《Journal of Agricultural Science and Technology(B)》 2012年第7期780-788,共9页
Planting plant such as Betung bamboo (Dendrocalamus asper (Schult f.) Backer ex Heyne) is one of the best ways for reducing global warming effect. Betung bamboo is giant grass (Poaceae) which has been traditiona... Planting plant such as Betung bamboo (Dendrocalamus asper (Schult f.) Backer ex Heyne) is one of the best ways for reducing global warming effect. Betung bamboo is giant grass (Poaceae) which has been traditionally used by Indonesian people for construction material since a long time ago. Poaceae family commonly has better carbon sink ability than trees because of its Ca photosynthesis mechanisms, but bamboo sub-family (Bambusoideae) lacks the Ca photosynthetic pathway and anatomy. In the absence of this feature the maximum possible productivity of bamboos is unlikely to greatly exceed that of other bioenergy crops with C3 photosynthesis such as fast growing tree species. This research proposed a sinusoidal equation as a basic equation for plant's daily photosynthesis light response curve fitting. The sinusoidal equation was success for Betung bamboo's daily photosynthesis light response curve fitting (R2 〉 60%). It had similar result in estimating carbon sink (82.35 kg/clump/year) compared to those which calculated by annual increment (69.01-107.82 kg/clump/year). It is better to choose sinusoidal equation than quadratic or cubic Betung bamboo is a good choice to be planted in order to resist the global warming effect because it has superior carbon sink capability (82.35 kg/clump/year) than slow growing tree, and equal to fast growing tree species, besides many other advantages. 展开更多
关键词 Carbon sink Betung bamboo daily photosynthesis light response sinusoidal curve fitting.
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Occurrence and light response of residual plastid genes in a Euglena gracilis bleached mutant strain OflB2
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作者 QIN Huan GUO Qingqing +5 位作者 LIU Chenchen LI Fenglan ZHANG Hua CHU Zihan WANG Jiangxin LEI Anping 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2020年第6期1858-1866,共9页
Euglena gracilis is a unicellular green eukaryotic microalga that features characteristics of both plants and animals.The photosynthetic function of its chloroplast is easily lost under stress resulting in bleached mu... Euglena gracilis is a unicellular green eukaryotic microalga that features characteristics of both plants and animals.The photosynthetic function of its chloroplast is easily lost under stress resulting in bleached mutants,while the physiological role of their residual plastid DNAs remains unclear.In this study,we obtained five bleached mutants by ofloxacin(Ofl)treatment,identified 12 residual plastid genes in five bleached mutants,and determined the mRNA levels in the wild type E.gracilis(WT)and one bleached mutant(OflB2)under dark and light stimulation conditions by quantitative reverse transcribed PCR(qRTPCR).Results show that the expression of all selected plastid genes in both WT and OflB2 mutant did not change significantly in darkness,while their responses to light stimulation were different.Under the light stimulation conditions,half of the genes did not change significantly,while most of the other genes were down-regulated in OflB2 mutant and up-regulated in WT.Therefore,the bleached mutant retains part of the plastid genome and the plastid relic is responsive to light.Our research will help to understand the functions of residual plastid DNA and evolution of chloroplasts. 展开更多
关键词 Euglena gracilis bleached mutant residual plastid genes light response
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New Preparation Method of Visible Light Responsive Titanium Dioxide Photocatalytic Films
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作者 Kaori Nishizawa Masahisa Okada Eiji Watanabe 《Materials Sciences and Applications》 2014年第3期112-123,共12页
We report a new and simple preparation method of the visible light responsive Titanium dioxide (TiO2) photocatalytic films using sol-gel method and ultraviolet light (UV) irradiation. Proposed films were prepared on f... We report a new and simple preparation method of the visible light responsive Titanium dioxide (TiO2) photocatalytic films using sol-gel method and ultraviolet light (UV) irradiation. Proposed films were prepared on fused silica plates using titanium tetra-isopropoxide, urea, 2-methoxyethanol, water and UV irradiation. The 650°C-annealed films were carbon-containing anatase type TiO2, not carbon-doped ones. The prepared films absorbed visible light with wavelengths longer than 400 nm. Also, organic dyes were effectively photodegradated by visible light irradiation in the presence of these films. 展开更多
关键词 TITANIUM Dioxide Films SOL-GEL Method UV IRRADIATION VISIBLE light responsIVE PHOTOCATALYST
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雷公藤多苷片对IgA肾病大鼠LIGHT-HVEM/LTβR通路的影响
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作者 王旭 方虹 +6 位作者 樊艳敏 季晗舒 宋珂 陈晨晨 卜继常 丁樱 宋纯东 《中国药理学通报》 CAS CSCD 北大核心 2024年第12期2277-2282,共6页
目的 基于炎症相关通路探讨雷公藤多苷片对IgA肾病大鼠肾脏的作用机制。方法 雄性SPF级SD大鼠,随机分为空白组、造模组。造模组采用联合“牛血清白蛋白+四氯化碳+脂多糖”建立IgA肾病大鼠模型。造模成功的大鼠随机分为模型组、泼尼松组... 目的 基于炎症相关通路探讨雷公藤多苷片对IgA肾病大鼠肾脏的作用机制。方法 雄性SPF级SD大鼠,随机分为空白组、造模组。造模组采用联合“牛血清白蛋白+四氯化碳+脂多糖”建立IgA肾病大鼠模型。造模成功的大鼠随机分为模型组、泼尼松组、雷公藤多苷片组,于第13周开始治疗组灌胃给药,给药4周后留取大鼠24 h尿液、血液、肾组织并检测尿红细胞数、24 h-UTP、BUN、Scr;ELISA检测血清IL-1β、TNF-α水平;HE染色观察各组大鼠肾组织病理学变化;Western blot及RT-PCR检测大鼠肾组织LIGHT、HVEM、LTβR蛋白及其mRNA的表达。结果 雷公藤多苷片明显降低IgA肾病大鼠尿红细胞数、24 h-UTP、BUN、Scr水平,改善肾组织病理,降低血清炎症因子IL-1β、TNF-α水平,降低肾组织中LIGHT、HVEM、LTβR蛋白及其mRNA表达水平。结论 雷公藤多苷片可能通过下调LIGHT-HVEM/LTβR信号通路,抑制免疫反应,减少炎症因子释放,从而减轻炎症反应,降低尿红细胞及尿蛋白,改善肾脏病理损伤,保护肾功能。 展开更多
关键词 雷公藤多苷片 IGA肾病 light-HVEM/LTβR 炎症 免疫反应 保护
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Construction of 2D-2D TiO_2 nanosheet/layered WS_2 heterojunctions with enhanced visible-light-responsive photocatalytic activity 被引量:8
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作者 Yongchuan Wu Zhongmin liu +3 位作者 Yaru Li Jitao Chen Xixi Zhu Ping Na 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第1期60-69,共10页
Constructing nanocomposites that combine the advantages of composite materials,nanomaterials,and interfaces has been regarded as an important strategy to improve the photocatalytic activity of TiO2.In this study,2D‐2... Constructing nanocomposites that combine the advantages of composite materials,nanomaterials,and interfaces has been regarded as an important strategy to improve the photocatalytic activity of TiO2.In this study,2D‐2D TiO2 nanosheet/layered WS2(TNS/WS2)heterojunctions were prepared via a hydrothermal method.The structure and morphology of the photocatalysts were systematically characterized.Layered WS2(~4 layers)was wrapped on the surface of TiO2 nanosheets with a plate‐to‐plate stacked structure and connected with each other by W=O bonds.The as‐prepared TNS/WS2 heterojunctions showed higher photocatalytic activity for the degradation of RhB under visible‐light irradiation,than pristine TiO2 nanosheets and layered WS2.The improvement of photocatalytic activity was primarily attributed to enhanced charge separation efficiency,which originated from the perfect 2D‐2D nanointerfaces and intimate interfacial contacts between TiO2 nanosheets and layered WS2.Based on experimental results,a double‐transfer photocatalytic mechanism for the TNS/WS2 heterojunctions was proposed and discussed.This work provides new insights for synthesizing highly efficient and environmentally stable photocatalysts by engineering the surface heterojunctions. 展开更多
关键词 WS2 TiO2 NANOSHEET Heterojunction Photocatalysis Visible‐light responsive
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Visible light responsive photocatalysts developed by substitution with metal cations aiming at artificial photosynthesis 被引量:2
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作者 Yuichi YAMAGUCHI Akihiko KUDO 《Frontiers in Energy》 SCIE CSCD 2021年第3期568-576,共9页
To solve resource,energy,and environmental issues,development of sustainable clean energy system is strongly required.In recent years,hydrogen has been paid much attention to as a clean energy.Solar hydrogen productio... To solve resource,energy,and environmental issues,development of sustainable clean energy system is strongly required.In recent years,hydrogen has been paid much attention to as a clean energy.Solar hydrogen production by water splitting using a photocatalyst as artificial photosynthesis is a promising method to solve these issues.Efficient utilization of visible light comprised of solar light is essential for practical use.Three strategies,i.e.,doping,control of valence band,and formation of solid solution are often utilized as the useful methods to develop visible light responsive photocatalysts.This minireview introduces the recent work on visible-light-driven photocatalysts developed by substitution with metal cations of those strategies. 展开更多
关键词 visible light responsive photocatalyst water splitting artificial photosynthesis:metal ion substitution
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Photocatalytic degradation of tetracycline hydrochloride with visible light-responsive bismuth tungstate/conjugated microporous polymer 被引量:1
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作者 Fenghongkang Pan Yimeng Wang +3 位作者 Kaiqing Zhao Jun Hu Honglai Liu Ying Hu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第1期488-496,共9页
Conjugated microporous polymer(CMP)is an emerging organic semiconductor withπ-conjugated skeletons,and the bandgap of CMP can be flexibly modulated to harvest visible light.Based on the diversity and adjustability of... Conjugated microporous polymer(CMP)is an emerging organic semiconductor withπ-conjugated skeletons,and the bandgap of CMP can be flexibly modulated to harvest visible light.Based on the diversity and adjustability of monomers in CMP,we designed and synthesized donor-accepter(D-A)type BTNCMP through Sonogashira-Hagihara cross-coupling polymerization,further in-situ constructing series of inorganic/organic Z-scheme BW/BTN-n composite in the presence of Bi_(2)WO_(6).After optimization,the tetracycline hydrochloride(C0=10 mg·L^(-1))degradation efficiency reached 84%with BW/BTN-2 as catalyst in 90 min under visible light irradiation,the apparent rate constant k1 is 0.017 min^(-1),which is 1.7 and 5.7 times higher than bare Bi_(2)WO_(6) and BTN-CMP.X-ray photoelectron spectra and UV-Vis diffuse spectra showed that the enhanced photocatalytic activity originated from the tight heterojunction between Bi_(2)WO_(6) and BTN-CMP,which can extend the light absorption range and facilitate the separation and transport of photogenerated charges in the interface of heterojunction.The active species trapping experiments and electron spin resonance technique revealed that h+was the dominant active species during the photodegradation process of tetracycline hydrochloride(TCH).The present study demonstrated the feasibility to construct inorganic/organic composite for the photocatalytic degradation of environmental pollutants. 展开更多
关键词 PHOTOCHEMISTRY Degradation Visible light response Pollution Inorganic/organic heterojunction composite
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Light-responsive adsorbentswithtunableadsorbent-adsorbate interactions forselective CO_(2) capture
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作者 Peng Tan Yao Jiang +5 位作者 Qiurong Wu Chen Gu Shichao Qi Qiang Zhang Xiaoqin Liu Linbing Sun 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第2期104-111,共8页
Amines in porous materials have been employed as active species for the selective CO_(2) adsorption from natural gas because of their target-specific interactions.Nevertheless,it is difficult to modulate such strong i... Amines in porous materials have been employed as active species for the selective CO_(2) adsorption from natural gas because of their target-specific interactions.Nevertheless,it is difficult to modulate such strong interactions to reach a high efficiency in the adsorption processes.Herein,we fabricated lightresponsive adsorbents with tunable adsorbent–adsorbate interactions for CO_(2) capture.The adsorbents were synthesized by introducing primary and secondary amines into a mesoporous silica that had been grafted with azobenzene groups on the surfaces.The target-specific amine sites render the adsorbents significantly selective in the uptake of CO_(2) over CH_(4),and the azobenzene groups were used as lightresponsive switches to influence the adsorbent–adsorbate interactions.The adsorbents can freely adsorb CO_(2) when the azobenzene groups are in the trans state.Ultraviolet-light irradiation makes the azobenzene groups transform to the cis configuration,which greatly hinders amines in the uptake of CO_(2).The caused difference of adsorption capacity can reach 34.9%.The alternative irradiation by ultravioletand visible-light can lead to a recyclable regulation on adsorption performance.The changes of the electrostatic potentials of amines are responsible for the light-induced regulation on adsorption. 展开更多
关键词 Adsorbents CO_(2)capture Selectivity light responsiveness AZOBENZENE
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Visible Light Responsive DNA Thermotropic Liquid Crystals Based on a Photothermal Effect of Gold Nanoparticles
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作者 Lei Zhang Yang Qu +5 位作者 Yun Liu Yawen Deng Jingjing Gu Zhongtao Wu Jiehua Lin Xiliang Luo 《Journal of Analysis and Testing》 EI 2021年第2期181-187,共7页
Solvent free DNA-surfactant melts are receiving continuous attractions in recent years.Their physical properties could be regulated via changing the alkyl chain length of surfactants.As an ideal external stimulus,ligh... Solvent free DNA-surfactant melts are receiving continuous attractions in recent years.Their physical properties could be regulated via changing the alkyl chain length of surfactants.As an ideal external stimulus,light has been used in the regulation of mechanical properties of DNA thermotropic liquid crystal(TLC)containing an azobenzene motif,while in this case,the UV light is the only effective excitation source.However,in comparison with visible light,UV light causes damage to DNA and has low tissue-penetration efficiency problem.In this work,a new type of DNA-didodecyldimethylammonium bromide(DNA-DDAB)TLCs fabricating with gold nanoparticles(AuNPs)was demonstrated.The visible light-induced photothermal effect of AuNPs could change the mechanical properties of AuNPs/DNA-DDAB TLCs,as shown by clearly boundary motion activity and viscoelasticity change.Furthermore,the ratio of AuNPs and charge stoichiometry of DNA:DDAB also affected photocurrent generation property of these DNA melts.The development of this visible light responsive DNA melt might facilitate the related studies in biomedicine and biomaterials. 展开更多
关键词 light responsive material Thermotropic liquid crystal Gold nanoparticle DNA melt Photothermal effect
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Comparative Gas Exchange of Ulmus crassifolia (Cedar Elm, Ulmaceae) and Ungnadia speciosa (Mexican Buckey, Sapindaceae) at Ambient and Elevated Levels of Light, CO2 and Temperature
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作者 Matthew B. Grunstra Oscar W. Van Auken 《American Journal of Plant Sciences》 2023年第6期691-709,共19页
Ulmus crassifolia Nutt. (Cedar elm, Ulmaceae) is a tree found in central and east Texas, northern Mexico, east to Florida, and north to southern Missouri and Oklahoma. Ungnadia speciosa Endl. (Mexican-buckeye, Sapinda... Ulmus crassifolia Nutt. (Cedar elm, Ulmaceae) is a tree found in central and east Texas, northern Mexico, east to Florida, and north to southern Missouri and Oklahoma. Ungnadia speciosa Endl. (Mexican-buckeye, Sapindaceae) is a shrub or small tree found in woodlands and savannas of central and western Texas, southern New Mexico and northern Mexico. In central Texas, both species are found in Juniperus ashei/Quercus virginiana woodlands or savannas or also at low density in inter-canopy grassland gaps or patches. Environmental conditions in this area are stressful because of shallow soils, high summer temperatures, and inconsistent low rainfall. Currently, both species have a low density in these areas, and Ulmus crassifolia is usually a tree, while Ungnadia speciosa is a woody understory shrub. This study suggests U. crassifolia and U. speciosa are tolerant or intermediate species, with juveniles starting in shade. Maximum photosynthetic rate (A<sub>max</sub>), dark respiration (R<sub>d</sub>), intercellular CO<sub>2</sub>, light saturation (L<sub>sp</sub>) and water use efficiency significantly increased when light levels and CO<sub>2</sub> concentrations were elevated for both species, but not when temperatures were elevated. Stomatal conductance decreased when the CO<sub>2</sub> concentration doubled, but there were few effects from elevated temperature. These findings suggest that U. speciosa and U. crassifolia should be more common and imply that they will have a higher density in a future high CO<sub>2</sub> environment. 展开更多
关键词 light response Gas Exchange Photosynthesis Respiration Water Use Efficiency
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Modified non-rectangular hyperbola equation with plant height for photosynthetic light-response curves of Potentilla anserina and Elymus nutans at various growth phases in the Heihe River Basin, Northwest China 被引量:1
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作者 LIU Junjie WANG Xiaoping +8 位作者 RONG Zhanlei GAO Yunfei ZHANG Guangde WANGWenbin GE Lijuan MAO Yahua GUO Zhaoxia WANG Qingtao ZHAO Chuanyan 《Journal of Arid Land》 SCIE CSCD 2019年第5期764-773,共10页
The non-rectangular hyperbola(NRH)equation is the most popular method that plots the photosynthetic light-response(PLR)curve and helps to identify plant photosynthetic capability.However,the PLR curve can't be plo... The non-rectangular hyperbola(NRH)equation is the most popular method that plots the photosynthetic light-response(PLR)curve and helps to identify plant photosynthetic capability.However,the PLR curve can't be plotted well by the NRH equation at different plant growth phases due to the variations of plant development.Recently,plant physiological parameters have been considered into the NRH equation to establish the modified NRH equation,but plant height(H),an important parameter in plant growth phases,is not taken into account.In this study,H was incorporated into the NRH equation to establish the modified NRH equation,which could be used to estimate photosynthetic capability of herbage at different growth phases.To explore photosynthetic capability of herbage,we selected the dominant herbage species Potentilla anserina L.and Elymus nutans Griseb.in the Heihe River Basin,Northwest China as the research materials.Totally,twenty-four PLR curves and H at different growth phases were measured during the growing season in 2016.Results showed that the maximum net photosynthetic rate and the initial slope of PLR curve linearly increased with H.The modified NRH equation,which is established by introducing H and an H-based adjustment factor into the NRH equation,described better the PLR curves of P.anserina and E.nutans than the original ones.The results may provide an effective method to estimate the net primary productivity of grasslands in the study area. 展开更多
关键词 plant height MODIFIED non-rectangular HYPERBOLA EQUATION Potentilla anserina Elymus nutans PHOTOSYNTHETIC light-response curve Qilian Mountains
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Study on the Photosynthetic Characteristics of Six Varieties(Strains)in Chinese Chestnut
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作者 Lizhi FU Yong YANG +6 位作者 Xiaoxiao KANG Meng WANG Jing LIU Xuan WANG Dongsheng WANG Liyang YU Hai’e ZHANG 《Agricultural Biotechnology》 2024年第1期9-14,57,共7页
[Objectives]This study was conducted to investigate the differences of photosynthetic physiological characteristics of different varieties(strains),which will provide a theoretical basis for high photosynthesis effici... [Objectives]This study was conducted to investigate the differences of photosynthetic physiological characteristics of different varieties(strains),which will provide a theoretical basis for high photosynthesis efficiency breeding and application in Chinese chestnut.[Methods]Six Chinese chestnut varieties of Castanea mollissima‘Yanbao’,C.mollissima‘Yanqiu’,C.mollissima‘Yanchang’,C.mollissima‘Yanjia’,C.mollissima‘Qianxi 37’,and C.mollissima‘Hybrid 22’were used as the materials.Using the portable photosynthesis system Li-6400,we measured the photosynthetic characteristics and diurnal variation of leaf samples of six different chestnut varieties or strains.We fitted the light response curves and photosynthetic parameters using the leaf floating model.Additionally,we determined the chlorophyll content in the leaves using a UV-visible spectrophotometer.[Results]Among the six chestnut varieties or strains,‘Yanqiu’exhibited a significantly higher photosynthetic light saturation point(P LSP)compared to other five varieties,and‘Hybrid 22’ranked second,indicating that these two varieties had the strongest adaptation to high light intensity.The photosynthetic light compensation point(P LCP)of‘Yanchang’was significantly higher than other five varieties,and"Qianxi 37"ranked second,indicating that these two varieties had the strongest adaptation to low light intensity.Additionally,they exhibited higher chlorophyll content and maintained good photosynthetic characteristics even in shaded environments with weak light stress.Varieties‘Yanbao’and‘Yanjia’showed higher P LSP and lower P LCP,indicating that these two varieties have a wider range of adaptation to light intensity.They were capable of efficiently utilizing light across a broader spectrum of intensities.‘Yanqiu’had the highest maximum net photosynthetic rate(P n,max)and the lowest dark respiration rate(R d),along with the highest chlorophyll content.It indicated that‘Yanqiu’has strong photosynthetic capacity and organic matter accumulation ability.It also had the highest P LSP,enabling it to fully utilize the high light environment of the Yanshan Mountains and possessed high light efficiency characteristics.The P n,max of‘Yanqiu’was significantly higher than other varieties.‘Hybrid 22’and‘Yanbao’also exhibited significantly higher P n,max compared with‘Yanjia’and‘Qianxi 37’.‘Yanchang’had the lowest P n,max.The order of P n,max among the six chestnut varieties or strains was as follows:‘Yanqiu’>‘Hybrid 22’>‘Yanbao’>‘Yanjia’>‘Qianxi 37’>‘Yanchang’.[Conclusions] 展开更多
关键词 Chinese chestnut Diurnal variation of photosynthesis light response model light response curve CHLOROPHYLL
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Cobalt ions enhance light responsiveness of carp cone horizontal cells in low calcium
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作者 王海龙 杨雄里 《Science China(Life Sciences)》 SCIE CAS 1996年第3期258-266,共9页
Effects of cobalt ions (Co2+) on horizontal cells in low extracellular calcium were examined in isolated, superfused carp retinas. While 0.1mmol/L Co2+ completely suppressed both rod- and cone-driven horizontal cells ... Effects of cobalt ions (Co2+) on horizontal cells in low extracellular calcium were examined in isolated, superfused carp retinas. While 0.1mmol/L Co2+ completely suppressed both rod- and cone-driven horizontal cells in normal Ringer’s solution, it enhanced light responses of cone horizontal cells in low (0.1mmol/L) calcium. The enhancement of the cone horizontal cell response by Co2+ was not caused by changes in light responsiveness of cone photoreceptors. Moreover, application of 50μmol/L IBMX, an inhibitor of phosphodiester enzyme, reduced the suppressive effect of 0.1 mmol/L Co2+ in normal Ringer’s solution. In consequence, the above-described enhancement of the cone horizontal cell light responsiveness may be due to a depolarization of cones caused by low calcium, which increases the activity of voltage-dependent calcium channels at cone terminals. 展开更多
关键词 light responsIVENESS horizontal cell low CALCIUM cobalt.
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A Novel Visible-light-responsive Photocatalyst Bi1.5Cr0.5WO6 with Suitable Bandgap Structure and Its Application in Water Decontamination
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作者 XIE Li-Yan LIU Ping +2 位作者 HUANG Li-Ting WANG Wan-Jun HUANG Jian-Hui 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2019年第6期930-940,共11页
Integrating the advantages of Bi and Cr elements in the bandgap engineering of metal oxides, a visible-light-responsive photocatalyst Bi1.5Cr0.5WO6 is successfully constructed and initially applied in water decontamin... Integrating the advantages of Bi and Cr elements in the bandgap engineering of metal oxides, a visible-light-responsive photocatalyst Bi1.5Cr0.5WO6 is successfully constructed and initially applied in water decontamination. The combination of UV-vis diffuses reflectance and the Mott-Schottky curve from electrochemical testing can be used to determine the conduction band and valence band of Bi1.5Cr0.5WO6 to be about –1.26 and 1.42 V, respectively. The location of energy band structure indicates that the superoxide free radical can be produced in Bi1.5Cr0.5WO6 photocatalytic system without hydroxyl group. This speculation is also confirmed by ESR experiment and active radical species scavenging experiments. In addition, the best photocatalytic performance of Bi1.5Cr0.5WO6 obtained under 180 ℃ is attributed to the smallest impedance and the strongest electronic migration capability. 展开更多
关键词 tungsten acid BISMUTH chromium VISIBLE-light response photocatalysis WATER DECONTAMINATION MALACHITE green
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Let the Spirit of Taking on Responsibility Release More Brilliant Light of the Era——On the Spirit of Taking on Responsibility of the Communist Party of China
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作者 Du Feijin Huang Yan 《Contemporary Social Sciences》 2017年第3期1-11,共11页
The 95-year great struggle of the Communist Party of China indicates profoundly that the CPC has always been following the trend of history, taking on the historical responsibility, bold in making great sacrifices, an... The 95-year great struggle of the Communist Party of China indicates profoundly that the CPC has always been following the trend of history, taking on the historical responsibility, bold in making great sacrifices, and reflects the selfless and fearless spirit of taking on responsibility. This spirit comes from the Chinese national spirit, the truth of Marxism and the great practice of revolution, construction and reform. The new requirements of the era must be clear and definite and the connotation of the era must be grasped, enabling the spirit of taking on responsibility to release more brilliant light of the era. First, it is striving for and dedicating selflessly of the country, and taking on historical responsibility to achieve the country's prosperity and strength. Second, it is serving the people, reducing difficulties and anxiety for the people and taking on historical responsibility to attain people's well-being. Third, it is sharing cares and burdens for the Party, keeping loyalty to the Party, and taking on historical responsibility so that the Party can provide a strong leadership core for the continued development of socialism with Chinese characteristics. The CPC is expected to produce new and more excellent answers to history and the people. 展开更多
关键词 the Communist Party of China the spirit of taking on responsibility light of the era
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弱光下锑基太阳电池的光谱响应与性能优化
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作者 曹宇 凌同 +6 位作者 曲鹏 王长刚 赵耀 那艳玲 江崇旭 胡子阳 周静 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2024年第2期519-526,共8页
锑基薄膜太阳电池因其制备方法简单,原材料丰富,光电性能稳定等优点而得到了快速发展。其中锑基吸光层材料(硫化锑、硫硒化锑、硒化锑)具有高吸收系数特点,因而在室内或者水下等弱光条件下具有相当大的应用潜力。通过构造两种衰减光谱... 锑基薄膜太阳电池因其制备方法简单,原材料丰富,光电性能稳定等优点而得到了快速发展。其中锑基吸光层材料(硫化锑、硫硒化锑、硒化锑)具有高吸收系数特点,因而在室内或者水下等弱光条件下具有相当大的应用潜力。通过构造两种衰减光谱以研究新型锑基薄膜太阳电池在弱光下的光电响应。首先通过厚度调节硒化锑太阳电池的吸光能力,发现当吸光层厚度较薄时,电池的光电转换效率存在较大差值;而当吸光层厚度过厚时,电池性能又因载流子复合的增大而降低。在吸光层厚度处于合适的0.4~1.2μm之间时,硒化锑太阳电池在长波衰减光谱和短波衰减光谱下都能获得高于16%的转换效率。然后通过硒含量调节锑基太阳电池的光谱吸收范围,发现长波衰减光谱下,锑基太阳电池的器件性能显著高于标准光谱,并且在20%~40%硒含量下能够获得最佳的转换效率。而在短波衰减光谱下,锑基太阳电池的最佳性能出现在硒含量为60%的情况下。因而在弱光条件下,锑基太阳电池的最佳硒含量需要通过具体的光谱特性确定。最后研究了两种衰减光谱下,硫化锑/硒化锑双结叠层太阳电池的光谱响应特性。发现在短波衰减光谱下,叠层太阳电池效率会随着总厚度的增加而增加。而在长波衰减光谱下,叠层太阳电池的最佳性能能够一直保持在较高水平。当叠层电池总厚度为2μm,且硫化锑顶电池厚度在0.5~1.2μm之间时,器件在两种衰减光谱下都能够实现光谱能量在两个子电池中的合理分配,使得叠层电池效率能够保持在20%以上。通过该研究对锑基太阳电池器件结构的合理设计,能够保证单结和双结器件在不同弱光条件下的高性能输出,为高环境适应性的锑基薄膜太阳电池的研发提供技术支持。 展开更多
关键词 锑基薄膜太阳电池 衰减光谱 弱光响应 吸光层厚度 转换效率
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