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Biobased Aromatic-Aliphatic Polyols from Cardanol by Photochemical Thiol-ene Reaction 被引量:1
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作者 Maha L.Shrestha Mihail Ionescu +1 位作者 Xianmei Wan Zoran S.Petrović 《Journal of Renewable Materials》 SCIE 2018年第5期504-516,共13页
Biobased aromatic-aliphatic polyols were previously synthesized from a thermal thiol-ene reaction of propoxylated cardanol with 2-mercaptoethanol(ME)in the presence of azobisisobutyronitrile(AIBN)as a radical initiato... Biobased aromatic-aliphatic polyols were previously synthesized from a thermal thiol-ene reaction of propoxylated cardanol with 2-mercaptoethanol(ME)in the presence of azobisisobutyronitrile(AIBN)as a radical initiator.Cardanol used for this purpose was obtained as a dark-brown liquid(Gardner Color Reference^18).The photochemical thiol-ene reaction can also be used to prepare aromatic-aliphatic polyols by employing cardanol.Via the photochemical thiol-ene reaction,2-mercaptoethanol was added successfully to C=C double bond of cardanol,suggesting that phenolic group may not play an inhibitory role in the radical thiol-ene reaction.However,we preferred to alkoxylate the phenolic hydroxyl group of cardanol,which is much more reactive with isocyanates than phenolic hydroxyls,to generate a new aliphatic hydroxyl group.Furthermore,the functionality of polyols was also improved by two methods:1)using 1-thio-glycerol instead of 2-mercaptoethanol and 2)using alkoxylated cardanol with glycidol(Cardanol-GLY)instead of propoxylated cardanol(Cardanol-PO).These polyols were then used in preparation of rigid polyurethane foams that can be useful in various applications such as insulation of freezers,pipes and storage tanks in food and chemical industries. 展开更多
关键词 CARDANOL photochemical reactions thiol-ene reaction 2-MERCAPTOETHANOL 1-thio-glycerol
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Environmental chamber study of the photochemical reaction of ethyl methyl sulfide and NO_x 被引量:2
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作者 WANG Kun DU Lin GE Maofa 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第2期137-141,共5页
A series of experiments were conducted in a self-made smog chamber at (300 + 1) K and 1.01 × 10^5 Pa to simulate the photochemical reaction of ethyl methyl sulfide (EMS) and NOx. The results showed that the ... A series of experiments were conducted in a self-made smog chamber at (300 + 1) K and 1.01 × 10^5 Pa to simulate the photochemical reaction of ethyl methyl sulfide (EMS) and NOx. The results showed that the higher the initial concentration of EMS, the more ozone was generated in the simulative reactions. It was found that the light intensity plays a very important role in the evaluation of ozone formation potential for EMS. The parameters of d(Oa-NO) and IR (incremental reactivity) were used to quantify the potential of EMS on ozone formation. The obtained maximum IR values in this article for the five simulative reactions were 1.55 × 10^-2, 0.99 × 10^-2, 1.36 × 10^-2, 2.47 × 10^-2, and 1.65 × 10^-2, respectively. A comparison between the results we obtained here and the results we obtained previously for di-tert-butyl peroxide and acetylene showed that the potential reactivity of EMS on ozone formation was at a relatively low level. 展开更多
关键词 smog chamber photochemical reaction ethyl methyl sulfide incremental reactivity
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Photochemical reaction between magnesium tetraphenyl porphyrin and oxygen 被引量:2
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作者 Jian Bin Zhang Peng Yan Zhang +2 位作者 Guo Hua Chen Fang Han Xiong Hui Wei 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第10期1190-1192,共3页
The photochemical reaction of magnesium tetraphenyl porphyrin (MgTPP) with O2 was studied in CH2Cl2 by steady-state fluorescence, UV-vis absorption, FTIR and MALDI-TOF MS measurements. These spectra indicate that O2... The photochemical reaction of magnesium tetraphenyl porphyrin (MgTPP) with O2 was studied in CH2Cl2 by steady-state fluorescence, UV-vis absorption, FTIR and MALDI-TOF MS measurements. These spectra indicate that O2 can react with MgTPP excited by irradiation, forming the stable 1:1 coordinated adduct of MgTPP-O2. In the adduct, the oxygen atoms of O2 may insert in the Mg-N bonds in MgTPP and bind with the nitrogen atoms of MgTPP to form N-O-Mg bonds. 展开更多
关键词 Magnesium tetraphenyl porphyrin photochemical reaction Linking oxygen
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Photochemical reaction of magnesium tetraphenyl porphyrin with sulfur dioxide 被引量:2
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作者 Jian Bin Zhang Chun Ping Li +5 位作者 Tian Rui Huo Zhan Ying Liu Li Hua Liu Tong Zhang Dong Yan Zhang Xiong Hui Wei 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第7期787-789,共3页
The photochemical reaction of magnesium tetraphenyl porphyrin(MgTPP) with sulfur dioxide(SO_2) was investigated in dichloromethane(CH_2Cl_2) by steady-state fluorescence,UV-vis absorption,MS,and XRD spectroscopi... The photochemical reaction of magnesium tetraphenyl porphyrin(MgTPP) with sulfur dioxide(SO_2) was investigated in dichloromethane(CH_2Cl_2) by steady-state fluorescence,UV-vis absorption,MS,and XRD spectroscopic techniques.These spectra showed that under irradiation MgTPP reacted with SO_2 to form 1:1 molecular adduct at first step.During the process of keeping irradiation and maintaining the flow of SO_2,SO_2 was reduced into S^(2-) by MgTPP and the results were detected using MS and XRD techniques.Understanding the photochemical reaction of MgTPP with SO_2 is of key interest in elucidating fundamental photochemical reaction mechanisms associated with this class of chlorophyll in the presence of SO_2. 展开更多
关键词 photochemical reaction Sulfur dioxide Magnesium tetraphenyl porphyrin(MgTPP)
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Photochemical reactions of poly(3-butoxythiophene-2,5-diyl) with chloroform 被引量:2
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作者 木合塔尔.依米提 YAMAMOTO Takakazu 帕提古丽.依明 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE EI CAS CSCD 2005年第8期722-724,共3页
Photochemical reactions of poly(3-butoxythiophene-2,5-diyl) with chloroform under irradiation with light were studied. The reactions were separately carried out under air, oxygen, and nitrogen. The obtained results sh... Photochemical reactions of poly(3-butoxythiophene-2,5-diyl) with chloroform under irradiation with light were studied. The reactions were separately carried out under air, oxygen, and nitrogen. The obtained results showed that this reaction belongs to the pseudo-first-order reaction with a rate constant kobs of 1.4×10?5 s?1 at room temperature. The presence or absence of air, oxygen, and nitrogen did not have obvious effects on the reaction rate under irradiation with light. 展开更多
关键词 Poly(3-butoxythiophene-2 5-diyl) photochemical reaction Kinetics
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Biobased Aromatic-Aliphatic Polyols by Thiol-Ene Reactions of Propoxylated Mercaptanized Cardanol
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作者 Maha L.Shrestha Mihail Ionescu +1 位作者 Xianmei Wan Thomas Upshaw 《Journal of Renewable Materials》 SCIE 2018年第6期630-641,共12页
Aromatic-aliphatic polyols were obtained previously from the thiol-ene reactions of propoxylated cardanol with hydroxyalkyl mercaptans;these aromatic-aliphatic polyols were then utilized in the preparation of rigid po... Aromatic-aliphatic polyols were obtained previously from the thiol-ene reactions of propoxylated cardanol with hydroxyalkyl mercaptans;these aromatic-aliphatic polyols were then utilized in the preparation of rigid polyurethane foams with excellent properties.The current work describes a variant of cardanol polyol synthesis by thiol-ene reactions in three steps.The first step is propoxylation of cardanol by reacting cardanol with propylene oxide;the second step is mercaptanization of propoxylated cardanol by reacting double bonds with hydrogen sulfide;and the third step involves the addition of the thiol groups of mercaptanized propoxylated cardanol to the double bonds of allyl alcohol,glycerol-1-allyl ether,and trimethylolpropane allyl ether.Thus,obtained polyols were characterized by standard analytical methods.Rigid polyurethane foams prepared from these polyols show promising physical-mechanical properties.The rigid polyurethane foams can be used for various applications such as thermo-insulation of freezers,storage tanks and pipes for food and chemical industries,wood substitutes and flotation materials. 展开更多
关键词 CARDANOL mercaptanized propoxylated cardanol photochemical thiol-ene reaction allyl alcohol glycerol-1-allyl ether trimethylolpropane allyl ether
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Theoretical Study of the Photochemical Reaction Mechanism of Bicyclo[4.1.0]heptane
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作者 WANG Yan-xia YE Song 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2006年第4期520-523,共4页
The photochemical reaction of bicyclo[4.1.0]heptane was studied at the complete active space SCF(CASSCF) level with a 6-31G^* basis set. A muhireference MP2 algorithm that has been implemented in the Gaussian progr... The photochemical reaction of bicyclo[4.1.0]heptane was studied at the complete active space SCF(CASSCF) level with a 6-31G^* basis set. A muhireference MP2 algorithm that has been implemented in the Gaussian program was used to correct the energetics for the dynamic correlation. Starting from the Franck-Condon excitation of bicyclo [ 4.1.0 ] heptane, the reaction is via two bonds' breakage to give rise to 1,6-heptdiene. One internal conversion (IC) and two intersystem crossing points(ISC) were located and are discussed separately. The reaction proceeds to its own characteristic product on the ground state. 展开更多
关键词 CASSCF Intersystem crossing photochemical reaction mechanism Internal conversion Bicyclo-[ 4.1.0 ] heptane 1-6 Heptadiene
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Photochemical reaction of particle-bound 1-nitropyrene under simulated atmospheric condition
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作者 Zhang Zhijia, Jin Zuliang, Zhu Naikai and Xu XiaobaiResearch Center for Eco-environmental Sciences,Academia Sinica,P.O.Box 934,100083,Beijing,China 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1989年第2期15-22,共8页
Photoreaction of particle-bound 1-nitropyrehe (1-NP) under simulated atmospheric condition has been studied. When 1-NP coated on the surface of silica gel was suspended in a stream of nitrogen, oxygen or air, respecti... Photoreaction of particle-bound 1-nitropyrehe (1-NP) under simulated atmospheric condition has been studied. When 1-NP coated on the surface of silica gel was suspended in a stream of nitrogen, oxygen or air, respectively, and exposed to intensive light of xenon lamp, photochemical reaction took place. The result of kinetic study showed it to be of the second order. The photoreaction products were identified by off-line HPLC/MS as 1,6-pyrenequinone, 1,8-pyrenequinone, trinitro-hydroxypyrene, dinitrohydroxypyrene, 6,6'- dipyrenenone, etc. The mutagenicity of photochemical reaction products is higher in oxygen and air, and lower in nitrogen than that of the precursor 1-NP, as detected by the Ames Bioassay. 展开更多
关键词 1-nitropyrene photochemical reaction.
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THE PHOTOCHEMICAL SYNTHESIS OF THE PYRIDINE ADDUCT OF TETRAPHENYLPORPHYRINATORHODIUM(Ⅱ)AND THE MECHANISM OF PHOTOCHEMICAL REACTION
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作者 A.K.Hsieh 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第4期279-280,共2页
A new rhodium(Ⅱ)porphyrin complex was isolated by chromatography from the photochemical reac- tion of(μ—tetraphenylporphyrinato)bis[dicarbonylrhodium(Ⅰ)]with pyridine in benzene and has been charac- terized.From t... A new rhodium(Ⅱ)porphyrin complex was isolated by chromatography from the photochemical reac- tion of(μ—tetraphenylporphyrinato)bis[dicarbonylrhodium(Ⅰ)]with pyridine in benzene and has been charac- terized.From the results,the reaction mechanism is proposed. 展开更多
关键词 TPP THE photochemical SYNTHESIS OF THE PYRIDINE ADDUCT OF TETRAPHENYLPORPHYRINATORHODIUM AND THE MECHANISM OF photochemical reaction
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THE SOLID STATE CONTROLLED PHOTOCHEMICAL REACTION OF NITROBENZALDEHYDE WITH INDOLE
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作者 Ji Ben MENG Da Ming DU +2 位作者 Guo Xiang XIONG Wen Guang WANG Yong Mei WANG 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第11期865-868,共4页
The solid state photochemical reaction of nitrobenzaldehyde with indole was investigated. Seven hey products were identified by IR, MS,^(1)H HMR and elemental analysis.
关键词 WANG THE SOLID STATE CONTROLLED photochemical reaction OF NITROBENZALDEHYDE WITH INDOLE HIGH
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Photochemical Reaction of 9,10-Anthraquinone Labeled Bovine Serum Albumin Conjugate
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作者 Qing Zhi ZHU Jin Gou XU +3 位作者 Xiang Qun GUO Xue Ying ZHENG Wen You LI Yi Bing ZHAO (The Research Laboratory of SEDC of Analytical Science for Material and Life Chemistry,Department of Chemistry, Xiamen University Xiamen 361005.)( Author to whom corresponde 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第3期221-224,共4页
Bovine serum albumin (BSA) was labeled with 9,10-anthraquinone and the photochemical fluorimetric reactivity of the covalently conjugated 9,10-anthraquinone was remarkably improved. The mechanism for the enhancement i... Bovine serum albumin (BSA) was labeled with 9,10-anthraquinone and the photochemical fluorimetric reactivity of the covalently conjugated 9,10-anthraquinone was remarkably improved. The mechanism for the enhancement in the photochemical reactivity of conjugated 9,10-anthraquinone with BSA was discussed. 展开更多
关键词 NM photochemical reaction of 9 10-Anthraquinone Labeled Bovine Serum Albumin Conjugate
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Photochemical Reactions of Microcystin-LR Following Irradiation with UV Light
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作者 Yoshihiro Mizukami 《Open Journal of Physical Chemistry》 2016年第4期79-85,共7页
Photochemical reactions of microcystin-LR, a toxic compound produced by some blue green algae, were investigated. Ultraviolet absorption of microcystin-LR was assessed. Time-dependent density functional theory (TDDFT)... Photochemical reactions of microcystin-LR, a toxic compound produced by some blue green algae, were investigated. Ultraviolet absorption of microcystin-LR was assessed. Time-dependent density functional theory (TDDFT) calculations indicated that absorption peak at 238 nm was mainly due to excitation of electrons from the linear chain structure Adda of microcystin-LR. Irradiation of microcystin-LR with UV light resulted in the reduction of the 238 nm absorption peak and the appearance of a new peak at 300 nm. Density functional theory (DFT) and TDDFT calculations with a model molecule suggested that this 300 nm peak was due to tricyclo-Adda microcystin-LR, an intermediate in photochemical reactions of microcystin-LR. Analysis of the rate of this photochemical reaction showed that it was a first order reaction. 展开更多
关键词 MICROCYSTIN-LR UV Irradiation UV Spectra DFT Calculations photochemical reactions
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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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Photochemical kinetics for holographic grating formation in phenanthrenequinone doped poly (methyl methacrylate) photopolymer
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作者 王健 孙秀冬 +2 位作者 骆素华 姜永远 孟庆鑫 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第10期4326-4332,共7页
The photochemical kinetics of phenanthrenequinone (PQ) doped poly (methyl methacrylate) photopolymer in holographic recording was studied theoretically and experimentally. The diffusion of PQ molecules during holo... The photochemical kinetics of phenanthrenequinone (PQ) doped poly (methyl methacrylate) photopolymer in holographic recording was studied theoretically and experimentally. The diffusion of PQ molecules during holographic recording was negligible because of its small diffusion coefficient at room temperature. A photochemical reaction kinetics model of PQ/PMMA was established. The analytical expressions for the temporal variations of transmittance and diffraction efficiency were derived. By fitting the experimental curves, some parameters related with the polymer components were obtained by the proposed model, which can be used to analyze the photochemical process and will be helpful to the optimization of material preparation. 展开更多
关键词 phenanthrenequinone doped poly(methyl methacrylate) photochemical reaction
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Eutectic Solution Enables Powerful Click Reaction for In-Situ Construction of Advanced Gel Electrolytes
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作者 Weixin Ye Jirong Wang +1 位作者 Chi Zhang Zhigang Xue 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第4期258-264,共7页
Thiol-ene click reaction is an intriguing strategy for preparing polymer electrolytes due to its high activity,atom economy and less side reaction.However,the explosive reaction rate and the use of non-electrolytic am... Thiol-ene click reaction is an intriguing strategy for preparing polymer electrolytes due to its high activity,atom economy and less side reaction.However,the explosive reaction rate and the use of non-electrolytic amine catalyst hamper its application in in-situ batteries.Herein,a nitrogen-containing eutectic solution is designed as both the catalyst of the thiol-ene reaction and the plasticizer to in-situ synthesize the gel polymer electrolytes,realizing a mild in-situ gelation process and the preparation of high-performance gel electrolytes.The obtained gel polymer electrolytes exhibit a high ionic conductivity of 4×10^(−4)S cm^(−1)and lithium-ion transference number(t_(Li)^(+))of 0.51 at 60°C.The as-assembled Li/LiFePO_(4)(LFP)cell delivers a high initial discharge capacity of 155.9 mAh g^(-1),and a favorable cycling stability with the capacity retention of 82%after 800 cycles at 1 C is also obtained.In addition,this eutectic solution significantly improves the rate performance of the LFP cell with high specific capacity of 141.5 and 126.8 mAh g^(-1)at 5 C and 10 C,respectively,and the cell can steadily work at various charge–discharge rate for 200 cycles.This powerful and efficient strategy may provide a novel way for in-situ preparing gel polymer electrolytes with desirable comprehensive performances. 展开更多
关键词 eutectic solution in-situ gelation lithium metal battery polymer electrolyte thiol-ene click reaction
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Functionalized Polyphosphoester via Living Ring-opening Polymerization and Photochemical Thiol-ene Click Reaction
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作者 WANG Ying WANG Qiliao +3 位作者 HOU Liman ZHOU Mingdong DONG Dewen ZHANG Ning 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2019年第2期340-344,共5页
Poly(ethylene phosphonate)was synthesized via the living ring-opening polymerization of cyclic phos-phonate monomer catalyzed by organocatalyst.The pendant vinyl ftmctionalities were employed to perform the pho-tochem... Poly(ethylene phosphonate)was synthesized via the living ring-opening polymerization of cyclic phos-phonate monomer catalyzed by organocatalyst.The pendant vinyl ftmctionalities were employed to perform the pho-tochemical click reactions wi&tMols.We demonstrated that both small thiol molecules and macromolecular thiols could be efficiently coupled into the PPE side chains,enabling the rapid and efficient functionalization of polyphos-phoesters(PPE). 展开更多
关键词 Cyclic PHOSPHONATE RING-OPENING polymerization thiol-ene click reaction Post modification
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济南市区典型污染时期大气中醛酮化合物的组分特征及生成机制
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作者 闫怀忠 王杰 +5 位作者 石敬华 曹燕燕 由希华 魏小锋 刘仕杰 张桂芹 《中国环境科学》 EI CAS CSCD 北大核心 2024年第1期72-82,共11页
利用2,4-二硝基苯肼采样管采样-高效液相色谱仪分析的方法,在济南市夏季典型臭氧污染时期(2022年6月14~22日)对两个不同市区点位(建大和创业园)大气中醛酮化合物开展同步采样分析,利用基于观测的化学箱式模型(OBM)对主要醛酮化合物的光... 利用2,4-二硝基苯肼采样管采样-高效液相色谱仪分析的方法,在济南市夏季典型臭氧污染时期(2022年6月14~22日)对两个不同市区点位(建大和创业园)大气中醛酮化合物开展同步采样分析,利用基于观测的化学箱式模型(OBM)对主要醛酮化合物的光化学反应进行模拟,识别主要醛酮化合物的二次生成途径及重要前体物.采样期间醛酮化合物总浓度为(19.78±9.83)×10^(-9),甲醛、乙醛和丙酮贡献率分别为36.75%、21.39%、14.64%,是最主要的醛酮化合物.建大点位甲醛浓度存在午间与夜间双峰高值,创业园点位甲醛浓度存在早晚高峰变化特征,两点位乙醛浓度呈“夜高昼低”日变化特征.两点位甲醛和乙醛特征比值(C1/C2)分别为1.97、1.47,乙醛和丙醛特征比值(C2/C3)分别为9.27、8.76,建大点位C1/C2存在明显的午间峰值.OBM模拟结果显示,甲醛最大生成速率为6.17×10^(-9)h^(-1),乙醛最大生成速率为1.67×10^(-9)h^(-1),丙酮最大生成速率为0.66×10^(-9)h^(-1),烷氧自由基(RO)+O_(2)反应是二次生成的主要途径.结合相对增量反应活性(RIR)结果发现,烯烃对济南市大气中甲醛和乙醛的二次生成有重要影响,乙烯、异戊二烯和丙烯是甲醛的重要前体物,丙烯和2-丁烯是乙醛的重要前体物,对人为烯烃重点排放行业进行科学合理管控将有利于阻抑大气中主要醛酮化合物的二次生成. 展开更多
关键词 醛酮化合物 组分特征 光化学反应 生成机制 OBM模型 臭氧
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南京北郊低对流层挥发性有机物垂直分布特征及对臭氧生成的潜在影响
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作者 施双双 朱彬 +2 位作者 沈利娟 杨思琪 王红磊 《地球科学与环境学报》 CAS 北大核心 2024年第4期513-527,共15页
在各地臭氧(O_(3))污染呈现多发态势的背景下,垂直方向上挥发性有机物(VOCs)对O_(3)生成的潜在贡献尚不明晰。利用南京北郊2020年10月17日至11月15日低对流层(高度为0~1000 m)强化探空数据,探讨了VOCs垂直分布特征及其对O_(3)生成的潜... 在各地臭氧(O_(3))污染呈现多发态势的背景下,垂直方向上挥发性有机物(VOCs)对O_(3)生成的潜在贡献尚不明晰。利用南京北郊2020年10月17日至11月15日低对流层(高度为0~1000 m)强化探空数据,探讨了VOCs垂直分布特征及其对O_(3)生成的潜在影响。结果表明:①VOCs总含量(体积分数,下同)随着高度的升高而降低((73.4±26.1)×10^(-9)~(50.4±20.3)×10^(-9)),各高度上烷烃占比最大(64.3%~71.6%),烯烃占比随着高度的升高而逐渐减小(3.4%~9.9%),芳香烃、卤代烃和乙炔占比无显著变化;交通排放和低边界层致使早、晚VOCs廓线垂直梯度大,低层VOCs积累且烷烃占比增大,而午后VOCs各组分垂直分布较均匀。②受大气层结影响,白天混合层内以烷烃和烯烃的光化学反应为主,OH自由基损失率(L_(OH))分别为3.3和2.7 s^(-1),占比分别为42.8%和35.1%;稳定边界层和残余层内均以烷烃和芳香烃的光化学反应为主。③午后混合层内VOCs的OH自由基损失率、臭氧生成潜势(OFP)与O_(3)含量成正相关关系,代表局地VOCs和O_(3)关系特征;早晨稳定边界层和残余层内无显著相关性;光化学反应活性较大的VOCs组分对O_(3)生成的潜在贡献主要集中在低层,以乙烯和丙烯为主;低对流层上部对O_(3)光化学生成的潜在贡献主要以低活性的烷烃为主,二甲苯/乙苯比值(X/E)分析表明,高层气团老化程度较高,可反映区域大气特征。限制化工厂排放、提升机动车排放标准和燃油质量是改善南京地区O_(3)污染的关键。 展开更多
关键词 挥发性有机物 垂直分布 臭氧 对流层 光化学反应活性 南京
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光响应的药物递送系统在眼科领域中的应用研究进展
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作者 林学琪(综述) 徐雯(审校) 《中华实验眼科杂志》 CAS CSCD 北大核心 2024年第7期663-668,共6页
刺激响应的药物递送系统可在外源性或内源性刺激下,在病变部位准确释放药物。光相较于其他刺激,具有非侵入性和时空特异性,且可以通过调整波长、功率以及照射时间等参数精确控制药物释放,受到了广泛的关注。眼球作为透明的光学系统,在... 刺激响应的药物递送系统可在外源性或内源性刺激下,在病变部位准确释放药物。光相较于其他刺激,具有非侵入性和时空特异性,且可以通过调整波长、功率以及照射时间等参数精确控制药物释放,受到了广泛的关注。眼球作为透明的光学系统,在光响应的药物递送系统应用方面具有独特的优势。本文综述了近十年来光响应的药物递送系统在眼科领域的应用研究进展,涵盖紫外光、可见光以及红外光在眼部的穿透深度、光能量和光毒性,眼部应用中光波段的选择,并综述了基于光裂解、光致异构化、光二聚化及光热转化的药物递送系统中的光敏基团和其发挥作用的机制。此外,本文还讨论了使用光响应的药物递送系统进行角膜药物渗透、眼后节药物输送以及治疗后发性白内障、脉络膜新生血管、眼内炎、难治性角膜炎等疾病的进展。虽然光响应的药物递送系统在眼科应用方面具有独特的优势,但是在未来的研究中需要进一步考虑光毒性、光热损伤、光敏基团的生物安全性以及光照频率、光照时间等安全性问题。 展开更多
关键词 药物递送系统 眼部给药 光响应 纳米载体 光化学反应
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光响应聚合物的结构动态调控
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作者 慕蓉 任浩浩 +2 位作者 龚雪艳 孙初锋 李佳 《山东化工》 CAS 2024年第12期100-103,109,共5页
近年来,动态光响应聚合物因其在光照条件下实现结构调控的先进性而备受关注。通过可逆的光化学反应,这类材料在特定波长和强度的光照下能够实现分子水平的精确控制,表现出卓越的性能和广泛的应用前景。本文深入探讨了结构可调的光响应... 近年来,动态光响应聚合物因其在光照条件下实现结构调控的先进性而备受关注。通过可逆的光化学反应,这类材料在特定波长和强度的光照下能够实现分子水平的精确控制,表现出卓越的性能和广泛的应用前景。本文深入探讨了结构可调的光响应主链聚合物、可逆光响应交联材料以及光响应超分子聚合物等关键领域。在综述中,详细总结了动态光响应聚合物在材料科学中的最新进展,为该领域的科学创新和应用拓展提供了系统性的参考和有价值的展望。 展开更多
关键词 光响应材料 动态结构调控 可逆光化学反应
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