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Here comes the sun:How optimization of photosynthetic light reactions can boost crop yields 被引量:2
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作者 Julia Walter Johannes Kromdijk 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2022年第2期564-591,共28页
Photosynthesis started to evolve some 3.5 billion years ago CO;is the substrate for photosynthesis and in the past 200-250 years,atmospheric levels have approximately doubled due to human industrial activities.However... Photosynthesis started to evolve some 3.5 billion years ago CO;is the substrate for photosynthesis and in the past 200-250 years,atmospheric levels have approximately doubled due to human industrial activities.However,this time span is not sufficient for adaptation mechanisms of photosynthesis to be evolutionarily manifested.Steep increases in human population,shortage of arable land and food,and climate change call for actions,now.Thanks to substantial research efforts and advances in the last century,basic knowledge of photosynthetic and primary metabolic processes can now be translated into strategies to optimize photosynthesis to its full potential in order to improve crop yields and food supply for the future.Many different approaches have been proposed in recent years,some of which have already proven successful in different crop species.Here,we summarize recent advances on modifications of the complex network of photosynthetic light reactions.These are the starting point of all biomass production and supply the energy equivalents necessary for downstream processes as well as the oxygen we breathe. 展开更多
关键词 BIOENGINEERING crop improvement electron transfer light reactions photosynthesis PHOTOSYSTEM stress tolerance
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Light olefin production by catalytic co-cracking of Fischer–Tropsch distillate with methanol and the reaction kinetics investigation 被引量:1
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作者 Hui Zou Teng Pan +4 位作者 Yanwen Shi Youwei Cheng Lijun Wang Yu Zhang Xi Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2020年第1期143-151,共9页
Catalytic co-cracking of Fischer–Tropsch(FT) light distillate and methanol combines highly endothermic olefin cracking reaction with exothermic methanol conversion over ZSM-5 catalyst to produce light olefins through... Catalytic co-cracking of Fischer–Tropsch(FT) light distillate and methanol combines highly endothermic olefin cracking reaction with exothermic methanol conversion over ZSM-5 catalyst to produce light olefins through a nearly thermoneutral process. The kinetic behavior of co-cracking reactions was investigated by different feed conditions: methanol feed only, olefin feed only and co-feed of methanol with olefins or F–T distillate. The results showed that methanol converted to C2–C6 olefins in first-order parallel reaction at low space time, methylation and oligomerization–cracking prevailed for the co-feed of methanol and C2–C5 olefins, while for C6–C8 olefins,monomolecular cracking was the dominant reaction whether fed alone or co-fed with methanol. For FT distillate and methanol co-feed, alkanes were almost un-reactive, C3–C5 olefins were obtained as main products, accounting for 71 wt% for all products. A comprehensive co-cracking reaction scheme was proposed and the model parameters were estimated by the nonlinear least square method. It was verified by experimental data that the kinetic model was reliable to predict major product distribution for co-cracking of FT distillate with methanol and could be used for further reactor development and process design. 展开更多
关键词 Fischer–Tropsch DISTILLATE CATALYTIC co-cracking light olefins METHANOL reaction kinetics
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Experimental study of intruder components in light neutron-rich nuclei via single-nucleon transfer reaction 被引量:6
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作者 Wei Liu Jian-Ling Lou +1 位作者 Yan-Lin Ye Dan-Yang Pang 《Nuclear Science and Techniques》 SCIE CAS CSCD 2020年第2期82-112,共31页
With the development of radioactive beam facilities,studies concerning the shell evolution of unstable nuclei have recently gained prominence.Intruder components,particularly s-wave intrusion,in the low-lying states o... With the development of radioactive beam facilities,studies concerning the shell evolution of unstable nuclei have recently gained prominence.Intruder components,particularly s-wave intrusion,in the low-lying states of light neutron-rich nuclei near N=8 are of importance in the study of shell evolution.The use of single-nucleon transfer reactions in inverse kinematics has been a sensitive tool that can be used to quantitatively investigate the single-particle orbital component of selectively populated states.The spin-parity,spectroscopic factor(or single-particle strength),and effective singleparticle energy can all be extracted from such reactions.These observables are often useful to explain the nature of shell evolution,and to constrain,check,and test the parameters used in nuclear structure models.In this article,the experimental studies of the intruder components in lowlying states of neutron-rich nuclei of He,Li,Be,B,and C isotopes using various single-nucleon transfer reactions are reviewed.The focus is laid on the precise determination of the intruder s-wave strength in low-lying states. 展开更多
关键词 Single-nucleon transfer reaction Intruder component light neutron-rich nuclei
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Theoretical analysis of the double-differential cross-sections of neutron,proton,deuteron,^(3)He,andαfor the p+^(6) Li reaction
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作者 Fang-Lei Zou Xiao-Jun Sun +10 位作者 Jing-Shang Zhang Hai-Rui Guo Yin-Lu Han Rui-Rui Xu Xi Tao Ji-Min Wang Xiao-Dong Sun Yuan Tian Tao Ye Yong-Li Xu Chun-Tian Liang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第3期181-197,共17页
Based on the unified Hauser–Feshbach and exciton model,which can describe the particle emission processes between discrete energy levels with energy,angular momentum,and parity conservations,a statistical theory of l... Based on the unified Hauser–Feshbach and exciton model,which can describe the particle emission processes between discrete energy levels with energy,angular momentum,and parity conservations,a statistical theory of light nucleus reaction(STLN)is developed to calculate the double-differential cross-sections of the outgoing neutron and light charged particles for the proton-induced^(6) Li reaction.A significant difference is observed between the p+^(6) Li and p+^(7) Li reactions owing to the discrepancies in the energy-level structures of the targets.The reaction channels,including sequential and simultaneous emission processes,are analyzed in detail.Taking the double-differential cross-sections of the outgoing proton as an example,the influence of contaminations(such as^(1) H,^(7)Li,^(12)C,and^(16)O)on the target is identified in terms of the kinetic energy of the first emitted particles.The optical potential parameters of the proton are obtained by fitting the elastic scattering differential cross-sections.The calculated total double-differential cross-sections of the outgoing proton and deuteron at E_(p)=14 MeV agree well with the experimental data for different outgoing angles.Simultaneously,the mixed double differential cross-sections of^(3) He andαare in good agreement with the measurements.The agreement between the measured data and calculated results indicates that the two-body and three-body breakup reactions need to be considered,and the pre-equilibrium reaction mechanism dominates the reaction processes.Based on the STLN model,a PLUNF code for the p+^(6) Li reaction is developed to obtain an ENDF-6-formatted file of the double-differential cross-sections of the nucleon and light composite charged particles. 展开更多
关键词 Statistical theory of light nucleus reaction p+^(6)Li reaction light composite charged particle Double-differential cross-sections Two-body breakup Three-body breakup
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Application of Simultaneous Technique of Capillary Zone Electrophoresis Photothermal Interference Spectrometry for Monitoring Chelating Reaction of Light Rare Earth with Tribromoarsenazo
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作者 Yong Gang HU Yan Zhuo DENG Jie Ke CHENG(Department of Chenustry, Center of Analysis and Testing, Wuhan Umversity, Wuhan 430072) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第5期425-426,共2页
A novel high sensihtity, small-volume photothermal intheence detector has beenintroduced for capillap zone electrophoresis separation analysis. The utility of thes sdriulboconstecheque for momtomp chelating reachon of... A novel high sensihtity, small-volume photothermal intheence detector has beenintroduced for capillap zone electrophoresis separation analysis. The utility of thes sdriulboconstecheque for momtomp chelating reachon of light rare earth with tribromoarsenazo has beenreported. 展开更多
关键词 Application of Simultaneous Technique of Capillary Zone Electrophoresis Photothermal Interference Spectrometry for Monitoring Chelating reaction of light Rare Earth with Tribromoarsenazo
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Evaluation of Reaction Mechanism for Photocatalytic Degradation of Dye with Self-Sensitized TiO<sub>2</sub>under Visible Light Irradiation
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作者 Md. Ashraful Islam Molla Ikki Tateishi +3 位作者 Mai Furukawa Hideyuki Katsumata Tohru Suzuki Satoshi Kaneco 《Open Journal of Inorganic Non》 2017年第1期1-7,共7页
The dye-sensitized TiO2 method is one of the most promising methods for the visible-light-induced detoxification of pollutants. The reaction mechanism for photocatalytic degradation of orange II (OII) and rhodamine B ... The dye-sensitized TiO2 method is one of the most promising methods for the visible-light-induced detoxification of pollutants. The reaction mechanism for photocatalytic degradation of orange II (OII) and rhodamine B (RhB) with self-sensitized TiO2 under visible light irradiation (λ > 400 nm) has been evaluated. Radical scavenger studies were carried out to investigate the active species involved in the photodegradation of 5 mg/L of initial concentration of OII and RhB at room temperature. The trapping effects of different scavengers results proved that the oxidation of OII and RhB mainly occurred by the direct oxidization of h+ and ·O2- radicals, while the ·OH radicals played only a relatively minor role in the direct oxidization process. 展开更多
关键词 TiO2 Photocatalytic Degradation Visible light DYE-SENSITIZATION reaction Mechanism
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Potential red-emitting phosphor GdNbO_4:Eu^(3+),Bi^(3+) for near-UV white light emitting diodes 被引量:2
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作者 Ding-fei Zhang An Tang +1 位作者 Liu Yang Zeng-tao Zhu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2012年第11期1036-1039,共4页
A red-emitting phosphor GdNbO4:Eu3+,Bi3+ was prepared by a high temperature solid-state reaction technique. The phosphor was characterized by X-ray diffraction (XRD), particle size analyzer and fluorescence spect... A red-emitting phosphor GdNbO4:Eu3+,Bi3+ was prepared by a high temperature solid-state reaction technique. The phosphor was characterized by X-ray diffraction (XRD), particle size analyzer and fluorescence spectrometer. The single phase of GdNbO4:Eu3+,Bi3+ was obtained at 1150~C and the average particle diameter was about 2.30 μm. Excitation and emission spectra reveal that the phosphor can be ef- ficiently excited by ultraviolet (UV) light (394 nm) and emit the strong red light of 612 nm due to the Eu3+ transition of SD0~TF2. The opti- mum content of Eu3+ doped in the phosphor GdNbOn:Eu3+ is 20mo1%. The phosphor Gdo.80NbO4:0.20Eu3+,0.03Bi3+ shows much stronger photoluminescence intensity and better chromaticity coordinates (x=0.642, 0.352) than GdNbO4:Eu3+. It is confirmed that Gdo.80NbO4:0.20Eu3+,0.03Bi3+ is a potential candidate for near-UV chip-based white light emitting diodes. 展开更多
关键词 PHOSPHORS solid-state reactions gadolinium niobate light emitting diodes
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Theoretical Analysis of Neutron Double-Differential Cross Sections of n +^9Be Reactions
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作者 段军锋 张竞上 +1 位作者 吴海城 孙小军 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第7期129-137,共9页
By using the nuclear reaction model for light nuclei, the calculations of the double-differential cross sections of outgoing neutrons from n +^9Be reactions are performed. The total outgoing neutrons are only come fr... By using the nuclear reaction model for light nuclei, the calculations of the double-differential cross sections of outgoing neutrons from n +^9Be reactions are performed. The total outgoing neutrons are only come from the (n, 2n)2a reaction channel. The (n, 2n)2a reaction channel is achieved through six different reaction approach, which are illustrated in this paper. The calculated results agree very well with the measured data at En = 7.1, 8.09, 8.17, 9.09, 9.97 and 10.26 MeV, because the updated level schemes related to the n + ^9Be reactions have been employed in this calculations. 展开更多
关键词 double-differential cross sections of total outgoing neutrons light nucleus reaction new levels
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Effects of Light Olefins Formation during Catalytic Pyrolysis of n-Heptane
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作者 Cheng Xiaojie Xie Chaogang Wei Xiaoli (SINOPEC Research Institute of Petroleum Processing, Beijing 100083) 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2011年第4期8-14,共7页
The influence of zeolite structure and process parameters (including reaction temperature and catalyst/oil ratio) on rules for formation of ethylene and propylene in the course of catalytic pyrolysis of n-heptane was ... The influence of zeolite structure and process parameters (including reaction temperature and catalyst/oil ratio) on rules for formation of ethylene and propylene in the course of catalytic pyrolysis of n-heptane was studied in a small- scale fixed fluid catalytic cracking unit. Test results have revealed that compared to the USY zeolite and Beta zeolite, the catalytic pyrolysis of n-heptane in the presence of the ZRP zeolite catalyst can result in higher yield and selectivity of ethyl- ene and propylene, while a higher reaction temperature and a higher catalyst/oil ratio can promote the formation of ethylene and propylene during catalytic pyrolysis of n-heptane. The ethylene formation reaction is more sensitive to the changes in reaction temperature, whereas the changes in catalyst/oil ratio are more influential to the propylene formation reaction. This paper has made a preliminary exploration into the different reaction pathways for formation of ethylene and propylene on zeolites with different structures. 展开更多
关键词 n-heptane catalytic pyrolysis light olefins reaction pathway
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The Photochemical Study of HSA and BSA with Resonance Light Scattering and Fluorescence Spectra 被引量:4
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作者 Liang, H Shen, XC +1 位作者 Li, F Jiang, ZL 《Chinese Chemical Letters》 SCIE CAS CSCD 2000年第3期251-254,共4页
The resonance light-scattering (RLS) of human serum albumin (HSA) and bovine serum albumin (BSA) is reported for the first time, and applied to study photochemical reaction of HSA and BSA. The fact of photocrosslinkin... The resonance light-scattering (RLS) of human serum albumin (HSA) and bovine serum albumin (BSA) is reported for the first time, and applied to study photochemical reaction of HSA and BSA. The fact of photocrosslinking self-association effect in HSA and BSA solutions is identified by the enhancement of RLS. The fluorescence quenching at about 350 nm and 700 nm proves that tryptophan (Trp) residues are one of the photochemical activity sites in HSA and BSA molecules. The Rayleigh scattering (RS) spectra of HSA and BSA that were neglected in fluorescence spectra before are found at about 296 nm, 592 nm and 888 nm for the first time, and are of adventageous to studying the aggregation of HSA or BSA. The possible photochemical reaction mechanism is also proposed. 展开更多
关键词 photochemical reaction photocrosslinking self-association effect resonance light-scattering serum albumin
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The Role of <i>P&tau;</i>in the Photothermoelectric Effect and in Photoredox Catalysis Reactions
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作者 Giovanna Scarel 《World Journal of Condensed Matter Physics》 2019年第4期91-101,共11页
Context and Background: Recent research has shown that the amount of energy conserved in light-matter interaction is given by the product of light’s power P times its period &tau;, i.e. P&tau;. To date, evide... Context and Background: Recent research has shown that the amount of energy conserved in light-matter interaction is given by the product of light’s power P times its period &tau;, i.e. P&tau;. To date, evidences of the validity of such finding are restricted to the interaction of light with capacitors, infrared spectroscopy, and vision in vertebrates. Motivation: In this article, we want to explore the validity of the role of P&tau;in a broader range of phenomena. Hypothesis: We assume that the photothermoelectric (PTE) effect and photoredox catalysis reactions (PCRs) are manifestations of light-matter interaction and therefore have P&tau;conserved in the process. Method: We take the data published in two articles, one on the PTE effect and the other on PCRs and revisit the data analysis of the authors of the original articles considering P&tau;as the energy conserved. Results: In the case of the PTE effect, we unveil that the size of the light’s beam cross-sectional area impinging on the photodetectors plays a major role in defining the performance of the photodetectors. With our analysis, the photodetector responsivities actually turn out to be higher than those reported in the original article. In the case of the PCRs, we find that the magnitude of P&tau;involved in successful PCRs is independent of the type of light used, whether near-infrared or blue. In addition, the involvement of P&tau;in the description of PCRs helps to clarify the role of the law of conservation of energy, which was neglected by the authors of the original article. Conclusions: From this study, we infer that the hypothesis that P&tau;that the hypothesis that represents the amount of energy conserved in light-matter interaction is valid and general, useful to measure device performance, and predict alternative processes to achieve desired outcomes. 展开更多
关键词 light-Matter Interaction Photothermoelectric Effect PHOTOREDOX reactionS
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The Application of Lights-Conversed Polyethylene Film for Agriculture
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作者 Zhang Ke\|li, Yuan Liang\|jie, Xi Mei\|yun, Yu You\|zu, Sun Ju\|tang College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, Hubei, China 《Wuhan University Journal of Natural Sciences》 CAS 2002年第3期365-367,共3页
Lanthanum-rhodamine (6G and B) complexes were synthesized by Rheological Phase Reaction Method. Lanthanum-rhodamine (6G and B) complexes doped polyethylene films which have a function of lights-conversion were prepare... Lanthanum-rhodamine (6G and B) complexes were synthesized by Rheological Phase Reaction Method. Lanthanum-rhodamine (6G and B) complexes doped polyethylene films which have a function of lights-conversion were prepared. The emission and excitation spectra were measured. The experiments of growing seedling and culture were carried out in the shed built with doped and undoped polyethylene films. Lanthanum-rhodamine doped polyethylene films which have a function of lights-conversion can efficiently convert the green light in the sunlight to the red light for photosynthesis of crops, to promote the maturing of crops and raise the yield of crops. 展开更多
关键词 LANTHANUM lights CONVERSION polyethylene film RHODAMINE rheological phase reaction
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Preliminary research on myosin light chain kinase in rabbit liver 被引量:6
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作者 Bin Ren~1 Hua-Qing Zhu~2 Zhao-Feng Luo~1 Qing Zhou~2 Yuan Wang~2 Yu-Zhen Wang~1 1 Department of Biochemistry and Molecular Biology,University of Science and Technology of China,Hefei 230027,Anhui Province,China2 Laboratory of Molecular Biology,Anhui Medical University,Hefei 230032,Anhui Province,China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2001年第6期868-871,共4页
AIM: To study preliminarily the properties of myosin light chain kinase (MLCK) in rabbit liver. METHODS: The expression of MLCK was detected by reverse transcription-polymerase chain reaction(RT-PCR); the MLCK was obt... AIM: To study preliminarily the properties of myosin light chain kinase (MLCK) in rabbit liver. METHODS: The expression of MLCK was detected by reverse transcription-polymerase chain reaction(RT-PCR); the MLCK was obtained from rabbit liver, and its activity was analyzed by gamma-(32)P incorporation technique to detect the phosphorylation of myosin light chain. RESULTS: MLCK was expressed in rabbit liver, and the activity of the enzyme was similar to rabbit smooth muscle MLCK, and calmodulin-dependent. When the concentration was 0.65 mg x L(-1), the activity was at the highest level. CONCLUSION: MLCK expressed in rabbit liver may catalyze the phosphorylation of myosin light chain, which may play important roles in the regulation of hepatic cell functions. 展开更多
关键词 ANIMALS HEPATOCYTES Liver Myosin light Chains Myosin-light-Chain Kinase PHOSPHORYLATION RABBITS Research Support Non-U.S. Gov't
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Scaling law of hydrogen evolution reaction for InSe monolayer with 3d transition metals doping and strain engineering 被引量:1
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作者 Chao Wang Yanyu Liu +2 位作者 Jian Yuan Ping Wu Wei Zhou 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第2期107-114,共8页
Recently, two dimensional In Se attracts great attentions as potential hydrogen production photocatalysts.Here, comprehensive investigations on the hydrogen evolution reaction activity of In Se monolayer with3 d trans... Recently, two dimensional In Se attracts great attentions as potential hydrogen production photocatalysts.Here, comprehensive investigations on the hydrogen evolution reaction activity of In Se monolayer with3 d transition metal doping and biaxial strain were performed based on the density functional theory.Transition metal dopants significantly increase the bonding strength between H and Se, and then adjust the hydrogen adsorption free energy to 0.02 e V by Zn doping. The enhanced hydrogen evolution reaction activity results from less electron occupying H 1 s-Se 4 pzanti-bonding states, which is well correlated with the pzband center level. Importantly, the universal scalling law was proposed to descript the evolution of hydrogen adsorption free energy including both doping and strain effects. Moreover, with appropriate band alignment, optical absorption, and carriers separation ability, Zn doped In Se monolayer is considered as a promising candidate of visible-light photocatalyst for hydrogen production. 展开更多
关键词 INSE MONOLAYER VISIBLE light PHOTOCATALYST Strain engineering 3d transition metals DOPING Hydrogen evolution reaction
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调Q激光与强脉冲光治疗面部雀斑的疗效比较
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作者 吴艳萍 徐瑞 +1 位作者 梁莉 黄铜 《中国美容医学》 CAS 2024年第12期111-115,共5页
目的:探究调Q激光与强脉冲光治疗面部雀斑的疗效及对皮损情况和不良反应的影响。方法:选取2021年1月-2022年9月就诊于笔者医院的130例面部雀斑患者,按就诊顺序随机分为对照组和观察组,每组65例。对照组采用强脉冲光治疗,观察组采用调Q... 目的:探究调Q激光与强脉冲光治疗面部雀斑的疗效及对皮损情况和不良反应的影响。方法:选取2021年1月-2022年9月就诊于笔者医院的130例面部雀斑患者,按就诊顺序随机分为对照组和观察组,每组65例。对照组采用强脉冲光治疗,观察组采用调Q激光治疗。比较两组治疗前后皮肤生理特征、美学效果及疗程、皮损情况、不良反应、患者美观满意度。结果:两组患者治疗期间不良反应总发生率比较差异无统计学意义(P>0.05),停止治疗3~6个月后均自行恢复。治疗前,两组患者斑点,纹理,皱纹,毛孔评分,皮损面积、颜色评分比较差异无统计学意义(P>0.05)。治疗1次后,两组皮肤生理状况及皮损状况均得到明显改善,且观察组上述评分均低于对照组(P<0.05);观察组美容治疗总有效率高于对照组(P<0.05)。观察组治疗时间及次数少于对照组(P<0.05)。两组患者美观满意度比较差异无统计学意义(P>0.05)。随访6个月后,所有患者无复发。随访1年后,两组复发率比较差异无统计学意义(P>0.05)。结论:与强脉冲光相比,调Q激光改善皮肤生理特征效果更好,治疗面部雀斑疗效更确切。调Q激光与强脉冲光治疗雀斑的近期疗效良好,但远期复发率较高。强脉冲光治疗雀斑的皮损情况少于调Q激光治疗。两者不良反应均较少,美观满意度相当。 展开更多
关键词 调Q激光 强脉冲光 面部雀斑 皮损情况 不良反应
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NaYSiO_(4)∶Ce^(3+)蓝色荧光粉的发光性质及其在白光发光二极管上的应用 被引量:1
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作者 陈蕾 杨星宇 +2 位作者 张瀚月 宋芳 冷稚华 《发光学报》 EI CAS CSCD 北大核心 2024年第5期745-752,共8页
采用高温固相法合成了NaYSiO_(4)∶xCe^(3+)(0.01≤x≤0.05)系列蓝色荧光粉。NaYSiO_(4)∶xCe^(3+)荧光粉在250~360 nm之间的宽带吸收能与紫外LED芯片很好地匹配。NaYSiO_(4)∶xCe^(3+)荧光粉中存在多个Ce^(3+)离子荧光中心,且在紫外光... 采用高温固相法合成了NaYSiO_(4)∶xCe^(3+)(0.01≤x≤0.05)系列蓝色荧光粉。NaYSiO_(4)∶xCe^(3+)荧光粉在250~360 nm之间的宽带吸收能与紫外LED芯片很好地匹配。NaYSiO_(4)∶xCe^(3+)荧光粉中存在多个Ce^(3+)离子荧光中心,且在紫外光激发下表现出峰值波长位于414 nm附近的宽带蓝光发射。NaYSiO_(4)∶0.02Ce^(3+)荧光粉在300~350 nm紫外光激发下量子效率在25%以上。NaYSiO_(4)∶0.02Ce^(3+)荧光粉表现出优良的化学稳定性,在水中浸泡14 d后荧光强度和量子效率几乎不变。将NaYSiO_(4)∶0.02Ce^(3+)蓝色荧光粉、商用(Sr,Ba)_2SiO_(4)∶Eu^(2+)绿色荧光粉和商用(Ca,Sr)AlSiN_(3)∶Eu^(2+)红色荧光粉涂覆于310 nm紫外LED芯片上制备得到了显色指数高达95的LED器件。当驱动电流从50 mA逐渐增大到300 mA时,制备的LED器件表现出稳定的暖白光发射,其色坐标几乎不变。上述结果说明,本研究报道的NaYSiO_(4)∶0.02Ce^(3+)蓝色荧光粉在紫外LED芯片驱动的白光发光二极管照明上有着潜在应用价值。 展开更多
关键词 NaYSiO_(4):Ce^(3+) 高温固相 蓝色荧光粉 白光发光二极管 高显色指数
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空心板栗状MAPbI_(3)/TiO_(2)的制备及可见光下降解甲苯研究
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作者 李荡 张杨 +3 位作者 董玮 李远勋 顾怀章 党铭铭 《云南大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第1期143-150,共8页
首先,以TiCl_(4)为钛源,采用水热法制备空心板栗状TiO_(2)载体.然后,再以PbI_(2)及MAI(MA=CH_(3)NH_(3)^(+))为前驱体,采用溶液法在空心板栗状TiO_(2)上一步构筑MAPbI_(3)薄膜,形成空心板栗状MAPbI_(3)/TiO_(2)复合光催化剂.以甲苯为目... 首先,以TiCl_(4)为钛源,采用水热法制备空心板栗状TiO_(2)载体.然后,再以PbI_(2)及MAI(MA=CH_(3)NH_(3)^(+))为前驱体,采用溶液法在空心板栗状TiO_(2)上一步构筑MAPbI_(3)薄膜,形成空心板栗状MAPbI_(3)/TiO_(2)复合光催化剂.以甲苯为目标降解物,考察板栗状MAPbI_(3)/TiO_(2)在可见光下的催化降解性能,并对材料的能级结构进行分析,揭示材料的降解机理.结果表明:钙钛矿型MAPbI_(3)薄膜的组成及形貌与PbI_(2)和MAI投料比密切相关,随着投料比的增加,薄膜的成分由MAPbI_(3)和MAI两相变为纯MAPbI_(3),再转变MAPbI_(3)和PbI_(2)两相.能级匹配、结构特殊的板栗状MAPbI_(3)/TiO_(2)不仅可以降低光生电子和空穴的复合率,还能有效地将光生电子和空穴分别转移至MAPbI_(3)的导带及TiO_(2)价带,促进活性粒子·O_(2)^(-)和·OH的生成,因此在甲苯的降解中表现更优的性能.在可见光的照射下,MAPbI_(3)/TiO_(2)对甲苯的降解率在90 min内可高达98%. 展开更多
关键词 空心板栗状 MAPbI_(3)/TiO_(2) 甲苯 可见光 反应机理
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红外偏振光照射联合经皮神经电刺激治疗颞下颌关节紊乱病的效果观察
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作者 季琦 徐秀清 +2 位作者 蔡娟 李薇 姚玉娟 《中国社区医师》 2024年第33期68-70,共3页
目的:分析红外偏振光照射(IPLI)联合经皮神经电刺激(TENS)治疗颞下颌关节紊乱病(TMD)的效果。方法:选取2022年4—12月南京医科大学附属口腔医院收治的120例TMD患者作为研究对象,随机分为观察组和对照组,各60例。对照组实施IPLI治疗,观... 目的:分析红外偏振光照射(IPLI)联合经皮神经电刺激(TENS)治疗颞下颌关节紊乱病(TMD)的效果。方法:选取2022年4—12月南京医科大学附属口腔医院收治的120例TMD患者作为研究对象,随机分为观察组和对照组,各60例。对照组实施IPLI治疗,观察组在对照组基础上实施TENS治疗。比较两组治疗效果。结果:治疗前,两组颞下颌关节功能障碍指数(DI)、肌肉触压痛指数(PI)、Fricton颞下颌关节紊乱指数(CMI)比较,差异无统计学意义(P>0.05);治疗后,两组DI、PI、CMI均低于治疗前,且观察组低于对照组(P<0.05)。治疗前,两组视觉模拟评分法(VAS)评分比较,差异无统计学意义(P>0.05);治疗后,两组VAS评分均低于治疗前,且观察组低于对照组(P<0.05)。两组不良反应总发生率比较,差异无统计学意义(P>0.05)。结论:IPLI联合TENS治疗TMD的临床效果显著,可改善患者颞下颌关节功能,减轻疼痛,且安全性高。 展开更多
关键词 红外偏振光照射 经皮神经电刺激 颞下颌关节紊乱病 疼痛 不良反应
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锌掺杂荧光硅量子点作为叶面光肥对生菜生长的影响
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作者 孙倩 崔曦鹏 +1 位作者 叶勇 何瑜 《湖北大学学报(自然科学版)》 CAS 2024年第2期182-190,共9页
以N-氨乙基-γ-氨丙基二甲氧基硅烷分子(DAMO)作为硅源,采用水热法合成一种高分散性、光学性能稳定的锌掺杂荧光硅量子点(Si@Zn QDs)。以Si@Zn QDs作为叶面光肥,吸收太阳光中不被植物利用的紫外光,发出能使生菜吸收进行光合作用的蓝光,... 以N-氨乙基-γ-氨丙基二甲氧基硅烷分子(DAMO)作为硅源,采用水热法合成一种高分散性、光学性能稳定的锌掺杂荧光硅量子点(Si@Zn QDs)。以Si@Zn QDs作为叶面光肥,吸收太阳光中不被植物利用的紫外光,发出能使生菜吸收进行光合作用的蓝光,提高了光能利用率。通过14 d的水培试验评估Si@Zn QDs作为叶面光肥对生菜生长的影响。结果表明,Si@Zn QDs与生菜的叶绿体(CLP)复合后,提高了希尔反应活性,当锌掺杂量达0.1%时,对生菜生长的促进效果最明显。与对照组相比,干质量和鲜质量分别增加41.64%和52.20%。Si@Zn 0.1%QDs(100 mg·L^(-1))使生菜叶片中叶绿素a、叶绿素b、总叶绿素、类胡萝卜素和蛋白质含量分别提高60.56%、56.37%、61.20%、49.75%和29.90%。这项工作为锌掺杂荧光硅量子点在植物光合作用中的应用提供了科学依据。 展开更多
关键词 锌掺杂荧光硅量子点 叶面光肥 希尔反应 光能利用率
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ICP-MS/MS测定轻质油中痕量氯含量
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作者 李爱阳 陈宇 +1 位作者 殷子懿 陈林 《石油学报(石油加工)》 EI CAS CSCD 北大核心 2024年第3期813-819,共7页
基于H_(2)反应模式下的质量转移反应消除干扰,建立电感耦合等离子体串联质谱(ICP-MS/MS)测定轻质油中痕量Cl的分析方法。轻质油经简单稀释后直接采用ICP-MS/MS进行测定,在MS/MS模式下使用H_(2)作为反应气,利用在碰撞/反应池(CRC)中Cl^(+... 基于H_(2)反应模式下的质量转移反应消除干扰,建立电感耦合等离子体串联质谱(ICP-MS/MS)测定轻质油中痕量Cl的分析方法。轻质油经简单稀释后直接采用ICP-MS/MS进行测定,在MS/MS模式下使用H_(2)作为反应气,利用在碰撞/反应池(CRC)中Cl^(+)与H_(2)发生二次H原子转移反应形成的子离子(H_(2)Cl^(+))进行测定,消除所有质谱干扰,获得Cl的灵敏度和检出限(LOD)明显优于O_(2)反应模式,LOD低至7.56μg/kg。通过与扇型磁场ICP-MS(SF-ICP-MS)对比分析标准参考物质NIST SRM 1634c,评价方法的准确可靠性。结果表明,标准参考物质的分析结果与认证值基本一致,相对标准偏差(RSD)为3.1%~4.7%,2种方法的对比分析结果在95%的置信度水平无显著性差异。所建立分析方法的灵敏度、准确度和和精密度高,MS/MS模式和H_(2)质量转移法的结合可无干扰测定轻质油中的Cl,适用于轻质油中痕量Cl的质量控制与评估。 展开更多
关键词 轻质油 电感耦合等离子体串联质谱 Cl 碰撞/反应池 H原子转移
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