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Direct Observation on H-Elimination Enhancement from C_(2)H_(4) through Non-Adiabatic Process by Femtosecond Laser Induced Coulomb Explosion

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Chinese Physics Letters 2024年第5期41卷 17-22页

作者：金无维王春成赵晓戈杨译章任殿相刘泽槿李孝开罗嗣佐丁大军 institute of Atomic and molecular Physics Jilin UniversityChangchun 130012China Jilin Provincial Key Laboratory of Applied Atomic and molecular Spectroscopy Jilin UniversityChangchun 130012China

Ethylene, the simplest model of a carbon-carbon double bond system, is pivotal in numerous chemical and biological processes. By employing intense infrared laser pump-probe techniques alongside coincidence measurements, we investigate the ultrafast non-adiabatic dynamics involved in the breakage of carbon-carbon double bonds and hydrogen elimination in dissociation of ethylene. Our study entails analyzing the dynamic kinetic energy release spectra to assess three bond-breaking scenarios, movements of nuclei, and structural changes around the carbon atoms. This allows us to evaluate the relaxation dynamics and characteristics of various dissociative states. Notably, we observe a significant rise in the yield of fragments resulting from C–H bond breakage with the delay time extended, suggesting non-adiabatic coupling through conical intersections from C–C bond breakage as a probable cause.

关键词： pump Femto adiabatic

Effect of sample temperature on femtosecond laser ablation of copper

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Chinese Physics B 2024年第2期33卷 377-385页

作者：党伟杰陈雨桐陈安民金明星 institute of Atomic and molecular Physics Jilin UniversityChangchun 130012China Jilin Provincial Key Laboratory of Applied Atomic and molecular Spectroscopy Jilin UniversityChangchun 130012China

We conduct an experimental study supported by theoretical analysis of single laser ablating copper to investigate the interactions between laser and material at different sample temperatures,and predict the changes of ablation morphology and lattice *** investigating the effect of sample temperature on femtosecond laser processing,we conduct experiments on and simulate the thermal behavior of femtosecond laser irradiating copper by using a two-temperature *** simulation results show that both electron peak temperature and the relaxation time needed to reach equilibrium increase as initial sample temperature *** the sample temperature rises from 300 K to 600 K,the maximum lattice temperature of the copper surface increases by about 6500 K under femtosecond laser irradiation,and the ablation depth increases by 20%.The simulated ablation depths follow the same general trend as the experimental *** work provides some theoretical basis and technical support for developing femtosecond laser processing in the field of metal materials.

关键词： femtosecond laser two-temperature model sample temperature ablation depth

Self-assembled amphiphilic NIR-Ⅱ emissive nano-micelles for imaging-guided photothermal therapy of colorectal cancer

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Science China Chemistry 2024年第8期67卷 2767-2774页

作者： Axin He Fangfang Xia Da Han Qinglai Yang Weihong Tan institute of molecular Medicine(IMM) Renji HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai 200240China Center for molecular Imaging Probe Hunan Province Key Laboratory of Cancer Cellular and Molecular PathologyCancer Research InstituteHengyang Medical SchoolUniversity of South ChinaHengyang 421001China The Key Laboratory of Zhejiang Province for Aptamers and Theranostics Zhejiang Cancer Hospital Hangzhou Institute of Medicine(HIM)Chinese Academy of SciencesHangzhou 310022China molecular Science and Biomedicine Laboratory(MBL) State Key Laboratory of Chemo/Biosensing and ChemometricsCollege of Chemistry and Chemical EngineeringCollege of BiologyAptamer Engineering Center of Hunan ProvinceHunan UniversityChangsha 410082China

Colorectal cancer(CRC) is one of the major causes of cancer-related mortality worldwide. Most near-infrared(NIR) agents used in clinical CRC treatment are at NIR-I(700–900 nm) window, which has limitations on deep tissue, and fluorescent probes in the second NIR(1,000–1,700 nm) allow high-resolution bioimaging with deep tissue penetration. However, existing NIR-II fluorophores used in clinical are still rare. Herein, based on shielding-donor-acceptor-donor-shielding(S-D-A-D-S) scaffold, we developed an organic small-molecule fluorophore IR-BTGP with NIR-II emission for imaging-guided photothermal therapy(PTT) in CRC mice model. Amphiphilic IR-BTGP can be self-assembled into spherical nano-micelles, which presents reliable water solubility and photothermal conversion efficiency(30.2%). In vitro experiments indicate that cancer cells treated with IRBTGP were significantly killed upon 808 nm light irradiation. Furthermore, in vivo NIR-II fluorescence imaging confirms that IR-BTGP accumulates in the tumor region. Remarkably, a significant tumor inhibition rate(78.5%) was observed in tumorbearing mice when treated with IR-BTGP plus 808 nm irradiation. Therefore, this work shows that IR-BTGP holds great promise as an NIR-II fluorescence imaging-guided PTT platform for CRC in the future.

关键词： photothermal therapy(PTT) second near-infrared(NIR-Ⅱ)imaging organic molecule

Optimization of extreme ultraviolet vortex beam based on high harmonic generation

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Chinese Physics B 2024年第5期33卷 459-464页

作者：肖礴赵逸文程方晶王革文姜威王一琛胡杰梁红静马日 institute of Atomic and molecular Physics Jilin UniversityChangchun 130012China College of Science Jilin Institute of Chemical TechnologyJilin 132022China

In high harmonic generation(HHG),Laguerre–Gaussian(LG) beams are used to generate extreme ultraviolet(XUV)vortices with well-defined orbital angular momentum(OAM),which have potential applications in fields such as microscopy and *** experimental study on the HHG driven by vortex and Gaussian beams is conducted in this *** is found that the intensity of vortex harmonics is positively correlated with the laser energy and gas *** structure and intensity distribution of the vortex harmonics exhibit significant dependence on the relative position between the gas jet and the laser *** ring-like structures observed in the vortex harmonics,and the interference of quantum paths provide an explanation for the distinct structural ***,by adjusting the relative position between the jet and laser focus,it is possible to discern the contributions from different quantum *** optimization of the HH vortex field is applicable to the XUV,which opens up a new way for exploiting the potential in optical spin or manipulating electrons by using the photon with tunable orbital angular momentum.

关键词： high harmonic generation phase matching extreme ultraviolet vortex beam quantum path interference

HSA shrinkage optimizes the photostability of embedded dyes fundamentally to amplify their efficiency as photothermal materials

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Chinese Chemical Letters 2024年第8期35卷 211-216页

作者： Yongkang Yue Zhou Xu Kaiqing Ma Fangjun Huo Xuemei Qin Kuanshou Zhang Caixia Yin Department Key Laboratory of Chemical biology and molecular Engineering of Ministry of Education Institute of Molecular ScienceShanxi UniversityTaiyuan 030006China Department Modern Research Center for Traditional Chinese Medicine Shanxi UniversityTaiyuan 030006China Research institute of Applied Chemistry Shanxi UniversityTaiyuan 030006China State Key Laboratory of Quantum Optics and Quantum Optics Devices Institute of Opto-ElectronicsShanxi UniversityTaiyuan 030006China

Focused on the performance promotion of organic small molecular dyes based photothermal agents via non-chemical modification,we found that heat-assisted binding of human serum albumin(HSA)to the dye causes shrinkage of the protein and encapsulate the dye to form *** revolutionizes the photostability of small molecule dyes which further improves their photothermal conversion effi-ciency and tumor ablation performance as photothermal agents *** this work,the obtained photothermal agent named HSA-P2-T could accumulate in tumor and induce 22℃enhancement of the tumor in xenograft models upon ultra-low dose(0.1 W/cm^(2))laser irradiation,which,as far as we know,is the lowest laser dose used in vivo photothermal *** HSA-P2-T,we realized tumor ablation upon twice intravenous injections of the nanoparticles and four photothermal treatments.

关键词： Photothermal therapy Cyanine dyes Photostability Albumin Encapsulation

TabHLH27 orchestrates root growth and drought tolerance to enhance water use efficiency in wheat

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Journal of Integrative Plant biology 2024年第7期66卷 1295-1312页

作者： Dongzhi Wang Xiuxiu Zhang Yuan Cao Aamana Batool Yongxin Xu Yunzhou Qiao Yongpeng Li Hao Wang Xuelei Lin Xiaomin Bie Xiansheng Zhang Ruilian Jing Baodi Dong Yiping Tong Wan Teng Xigang Liu Jun Xiao Key Laboratory of Plant Cell and Chromosome Engineering Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Center for Agricultural Resources Research Institute of Genetics and Developmental BiologyChinese Academy of SciencesShijiazhuang 050022China Key Laboratory of Crop biology College of Life SciencesShandong Agricultural UniversityTai'an 271018China State Key Laboratory of Crop Gene Resources and Breeding Institute of Crop SciencesChinese Academy of Agricultural SciencesBeijing 100081China Ministry of Education Key Laboratory of molecular and Cellular biology Hebei Research Center of the Basic Discipline of Cell BiologyHebei Collaboration Innovation Center for Cell Signaling and Environmental AdaptationHebei Key Laboratory of Molecular and Cellular BiologyCollege of Life SciencesHebei Normal UniversityShijiazhuang 050024China Centre of Excellence for Plant and Microbial Science(CEPAMS) JIC‐CASBeijing 100101China

Cultivating high-yield wheat under limited water resources is crucial for sustainable agriculture in semiarid *** water scarcity,plants activate drought response signaling,yet the delicate balance between drought tolerance and development remains *** genome-wide association studies and transcriptome profiling,we identified a wheat atypical basic helix-loop-helix(b HLH)transcription factor(TF),Tab HLH27-A1,as a promising quantitative trait locus candidate for both relative root dry weight and spikelet number per spike in *** HLH27-A1/B1/D1 knockout reduced wheat drought tolerance,yield,and water use efficiency(WUE).Tab HLH27-A1 exhibited rapid induction with polyethylene glycol(PEG)treatment,gradually declining over *** activated stress response genes such as Ta CBL8-B1 and Ta CPI2-A1 while inhibiting root growth genes like Ta SH15-B1 and Ta WRKY70-B1 under short-term PEG *** distinct transcriptional regulation of Tab HLH27-A1 involved diverse interacting factors such as Ta ABI3-D1 and Tab *** variations of Tab HLH27-A1influence its transcriptional responses to drought stress,with Tab HLH27-A1^(Hap-II)associated with stronger drought tolerance,larger root system,more spikelets,and higher WUE in ***,the excellent Tab HLH27-A1^(Hap-II)was selected during the breeding process in China,and introgression of Tab HLH27-A1^(Hap-II)allele improved drought tolerance and grain yield,especially under water-limited *** study highlights Tab HLH27-A1's role in balancing root growth and drought tolerance,providing a genetic manipulation locus for enhancing WUE in wheat.

关键词： drought tolerance GWAS root growth wheat WUE

CONSTANS alters the circadian clock in Arabidopsis thaliana

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molecular Plant 2024年第8期17卷 1204-1220页

作者： Pedro de los Reyes Gloria Serrano-Bueno Francisco J.Romero-Campero He Gao Jose M.Romero Federico Valverde Plant Development Group-institute for Plant Biochemistry and Photosynthesis Consejo Superior de Investigaciones CientificasUniversidad de SevillaSevilleSpain Department of Computer Science and Artificial Intelligence Universidad de SevillaSevilleSpain Department of Plant Developmental biology Max Planck Institute for Plant Breeding ResearchCologneGermany Department of Plant Biochemistry and molecular biology Universidad de SevillaSevilleSpain

Plants are sessile organisms that have acquired highly plastic developmental strategies to adapt to the *** these processes,the floral transition is essential to ensure reproductive success and is finelyregulated by several internal andexternal genetic *** photoperiodic pathway,which controls plant response to day length,is one of the most important pathways controlling *** Arabidopsis photoperiodic flowering,CONSTANS(CO)is the central gene activating the expression of the florigen FLOWERING LOCUS T(FT)in the leaves at the end of a long *** circadian clock strongly regulates Co ***,to date,no evidence has been reported regarding a feedbackloop from the photoperiod pathway back to the circadian *** transcriptional networks,we have identified relevant network motifs regulating the interplay between the circadian clock and the photoperiod *** expression,chromatin immunoprecipitation experiments,and phenotypic analysis allowed us to elucidate the role of Co over the circadian *** with altered cO expression showed a different internal clock period,measured by daily leaf rhythmic *** showed that co upregulates the expression of key genes related to the circadian clock,such as CCA1,LHY,PRR5,and Gl,at the end of a long day by bindingto specific sites on their ***,a high numberof PRR5-repressed target genes are upregulated by CO,and this could explain the phase transition promoted by *** CO-PRR5 complex interacts with the bZiP transcriptionfactor HY5andhelps to localize the complex in the promoters of clock *** together,our results indicate that there may be a feedback loop in which co communicates back to the circadian clock,providing seasonal information to the circadian system.

关键词： CONSTANS circadian clock photoperiod

Classification and progress of extraction technologies for nonferrous metal resources

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Science China Chemistry 2024年

作者： Fangqin Cheng Na Zhou Nazeer Muhammad Nouman Li Cui Caixia Yin institute of Resources and Environmental Engineering State Environmental Protection Key Laboratory of Efficient Utilization of Coal Waste Resources Shanxi University Key Laboratory of Chemical biology and molecular Engineering of Ministry of Education Institute of Molecular ScienceShanxi University

In recent years, the demand for strategic metal resources, essential for scientific and technological progress and industrial development, has multiplied. Ensuring a stable supply of these metals is critical to national security and the well-being of the population. As global industrialization accelerates, the daily demand for nonferrous metals continues to rise. Consequently,extracting and recovering strategic metals from low-grade raw materials, such as solid waste, has become crucial for maintaining their supply and economic development. However, the extraction process is fraught with challenges, including mineral phase stability and complex composition. This review focuses on key strategic metals such as lithium, aluminum, gallium, and vanadium. It introduces and examines various methods for extracting nonferrous metals from different raw materials, including traditional mining technologies applied to low-grade solid wastes. It also outlines future development opportunities and challenges in this field.

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Understanding the cooperative effects in the catalysis of homodimeric fluoroacetate dehalogenase

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Science China Chemistry 2024年第7期67卷 2382-2391页

作者： Ke-Wei Chen Jia-Nan Chen Jun Zhang Chao Wang Tian-Yu Sun Yun-Dong Wu Key Laboratory of Computational Chemistry and Drug Design State Key Laboratory of Chemical OncogenomicSchool of Chemical Biology and BiotechnologyPeking University Shenzhen Graduate SchoolShenzhen 518055China institute of Chemical biology Shenzhen Bay LaboratoryShenzhen 518132China College of Chemistry and molecular Engineering Peking UniversityBeijing 100871China Changping Laboratory Beijing 102200China

Fluoroacetate dehalogenases(FAcD),a homodimeric enzyme,catalyzes the conversion of fluoroacetic acid to glycolic acid(GoA).It has been proved that the enzyme has a half-of-the-site ***,its catalytic(C)subunit converts the first substrate to a covalent intermediate;then,the non-catalytic(NC)subunit binds a second substrate and promotes the conversion of the intermediate in the C subunit into the final *** the release of the product,the C subunit becomes the NC subunit,and the previous NC subunit becomes the C *** elucidate the detailed mechanism behind this cooperative catalysis,we have conducted microsecond-scale MD simulations along the reaction *** simulations indicate that the substrate in the NC subunit induces W185 and Y141 adopting an open conformation in the C *** opening of W185(C)facilitates the entry of catalytic water,enhancing the catalytic activity for product formation,while the opening of Y141(C)creates an unfavorable environment for product binding,promoting its *** interaction network analysis reveals that the substrate in the NC subunit can induce conformational changes through a conserved water chain at the interface.

关键词： enzyme catalysis molecular dynamics cooperative effect pre-reaction state