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电子和质子辐照^(100)Mo制备^(99)Mo/^(99)mTc对比实验 被引量:1
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作者 陈德胜 黄清钢 +1 位作者 曹石巍 秦芝 《同位素》 2025年第1期30-38,共9页
^(99)Mo/^(99)mTc是全球应用最广泛的医用显影核素,目前的供应依赖几座濒临退役的核反应堆。相比反应堆而言,加速器的建造、运行及维护成本更低,布局更灵活。因此,粒子加速器制备^(99)Mo/^(99)mTc已成为研究热点,其中利用电子加速器辐照... ^(99)Mo/^(99)mTc是全球应用最广泛的医用显影核素,目前的供应依赖几座濒临退役的核反应堆。相比反应堆而言,加速器的建造、运行及维护成本更低,布局更灵活。因此,粒子加速器制备^(99)Mo/^(99)mTc已成为研究热点,其中利用电子加速器辐照^(100)Mo制备^(99)Mo和质子加速器辐照^(100)Mo制备^(99)mTc是最具可行性的两种方法。本研究结合实验数据和蒙特卡洛模拟结果,对比了两种基于加速器制备^(99)Mo/^(99)mTc的优势和劣势。质子辐照^(100)Mo直接产生^(99)mTc,^(99)mTc产额高,但伴生Tc的其他同位素,尤其是^(99)gTc。而电子辐照^(100)Mo,可以产生高纯的^(99)Mo,且化学分离过程简单,能够制备成^(99)Mo-^(99)mTc发生器使用,相对更具优势。 展开更多
关键词 质子 电子 加速器 蒙特卡罗模拟 ^(99)Mo/^(99)mtc
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Copper complexes of anthrahydrazone bearing pyridyl side chain:Synthesis,crystal structure,anticancer activity,and DNA binding 被引量:1
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作者 HUANG Yao WU Yingshu +5 位作者 BAO Zhichun HUANG Yue TANG Shangfeng LIU Ruixue LIU Yancheng LIANG Hong 《无机化学学报》 北大核心 2025年第1期213-224,共12页
To expand the study on the structures and biological activities of the anthracyclines anticancer drugs and reduce their toxic side effects,the new anthraquinone derivatives,9‑pyridylanthrahydrazone(9‑PAH)and 9,10‑bisp... To expand the study on the structures and biological activities of the anthracyclines anticancer drugs and reduce their toxic side effects,the new anthraquinone derivatives,9‑pyridylanthrahydrazone(9‑PAH)and 9,10‑bispyridylanthrahydrazone(9,10‑PAH)were designed and synthesized.Utilizing 9‑PAH and 9,10‑PAH as promising anticancer ligands,their respective copper complexes,namely[Cu(L1)Cl_(2)]Cl(1)and{[Cu_(4)(μ_(2)‑Cl)_(3)Cl_(4)(9,10‑PAH)_(2)(DMSO)_(2)]Cl_(2)}_(n)(2),were subsequently synthesized,where the new ligand L1 is formed by coupling two 9‑PAH ligands in the coordination reaction.The chemical and crystal structures of 1 and 2 were elucidated by IR,MS,elemental analysis,and single‑crystal X‑ray diffraction.Complex 1 forms a mononuclear structure.L1 coordinates with Cu through its three N atoms,together with two Cl atoms,to form a five‑coordinated square pyramidal geometry.Complex 2 constitutes a polymeric structure,wherein each structural unit centrosymmetrically encompasses two five‑coordinated binuclear copper complexes(Cu1,Cu2)of 9,10‑PAH,with similar square pyramidal geometry.A chlorine atom(Cl_(2)),located at the symmetry center,bridges Cu1 and Cu1A to connect the two binuclear copper structures.Meanwhile,the two five‑coordinated Cu2 atoms symmetrically bridge the adjacent structural units via one coordinated Cl atom,respectively,thus forming a 1D chain‑like polymeric structure.In vitro anticancer activity assessments revealed that 1 and 2 showed significant cytotoxicity even higher than cisplatin.Specifically,the IC_(50)values of 2 against HeLa‑229 and SK‑OV‑3 cancer cell lines were determined to be(5.92±0.32)μmol·L^(-1)and(6.48±0.39)μmol·L^(-1),respectively.2 could also block the proliferation of HeLa‑229 cells in S phase and significantly induce cell apoptosis.In addition,fluorescence quenching competition experiments suggested that 2 might interact with DNA by an intercalative binding mode,offering insights into its underlying anticancer mechanism.CCDC:2388918,1;2388919,2. 展开更多
关键词 anthrahydrazone metal complex crystal structure anticancer activity cell apoptosis
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Data-Driven Prediction in Complex Systems of Virus Evolution and Global Warming 被引量:1
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作者 LUO Liaofu LÜJun 《内蒙古大学学报(自然科学版)》 2025年第1期1-7,共7页
A complex system is inherently high-dimensional.Recent studies indicate that,even without complete knowledge of its evolutionary dynamics,the future behavior of such a system can be predicted using time-series data(da... A complex system is inherently high-dimensional.Recent studies indicate that,even without complete knowledge of its evolutionary dynamics,the future behavior of such a system can be predicted using time-series data(data-driven prediction).This suggests that the essential dynamics of a complex system can be captured through a low-dimensional representation.Virus evolution and climate change are two examples of complex,time-varying systems.In this article,we show that mutations in the spike protein provide valuable data for predicting SARS-CoV-2 variants,forecasting the possible emergence of the new macro-lineage Q in the near future.Our analysis also demonstrates that carbon dioxide concentration is a reliable indicator for predicting the evolution of the climate system,extending global surface air temperature(GSAT)forecasts through 2500. 展开更多
关键词 data-drivenprediction complex system virus evolution global warming
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Exploring the Effects of Background Image Complexity and Map Symbol Load on the Usability of Image-maps 被引量:1
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作者 PENG Qian XIA Yuxin QIU Zeren 《Journal of Geodesy and Geoinformation Science》 2025年第2期5-20,共16页
Image-maps,a hybrid design with satellite images as background and map symbols uploaded,aim to combine the advantages of maps’high interpretation efficiency and satellite images’realism.The usability of image-maps i... Image-maps,a hybrid design with satellite images as background and map symbols uploaded,aim to combine the advantages of maps’high interpretation efficiency and satellite images’realism.The usability of image-maps is influenced by the representations of background images and map symbols.Many researchers explored the optimizations for background images and symbolization techniques for symbols to reduce the complexity of image-maps and improve the usability.However,little literature was found for the optimum amount of symbol loading.This study focuses on the effects of background image complexity and map symbol load on the usability(i.e.,effectiveness and efficiency)of image-maps.Experiments were conducted by user studies via eye-tracking equipment and an online questionnaire survey.Experimental data sets included image-maps with ten levels of map symbol load in ten areas.Forty volunteers took part in the target searching experiments.It has been found that the usability,i.e.,average time viewed(efficiency)and average revisits(effectiveness)of targets recorded,is influenced by the complexity of background images,a peak exists for optimum symbol load for an image-map.The optimum levels for symbol load for different image-maps also have a peak when the complexity of the background image/image map increases.The complexity of background images serves as a guideline for optimum map symbol load in image-map design.This study enhanced user experience by optimizing visual clarity and managing cognitive load.Understanding how these factors interact can help create adaptive maps that maintain clarity and usability,guiding AI algorithms to adjust symbol density based on user context.This research establishes the practices for map design,making cartographic tools more innovative and more user-centric. 展开更多
关键词 remote sensing image map point label complexity
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Zircon U-Pb-Hf and Trace Element Signatures Reveal the Petrogenesis of the Jiuyishan Granitic Complex,South China:Implications for W-Sn and Rare Metal Mineralization 被引量:1
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作者 Wenzhou Xiao Chaoyun Liu +6 位作者 Kaixuan Tan Xianzhe Duan Qinglin Sui Kaituo Shi Peng Feng Mabrouk Sami Quan Ou 《Journal of Earth Science》 2025年第3期1069-1089,共21页
The Jiuyishan granitic complex,located in the Nanling Range,South China,is composed of five granitic plutons(Xuehuading,Jinjiling,Pangxiemu,Shaziling and Xishan).Zircon U-Pb dating of four plutons(Jinjiling,Pangxiemu,... The Jiuyishan granitic complex,located in the Nanling Range,South China,is composed of five granitic plutons(Xuehuading,Jinjiling,Pangxiemu,Shaziling and Xishan).Zircon U-Pb dating of four plutons(Jinjiling,Pangxiemu,Shaziling and Xishan)yielded similar ages of approximately 153 Ma,indicating indistinguishable ages within error.Three plutons except the Shaziling pluton,have consistentε_(Nd)(t)(-7.8 to-5.8)andε_(Hf)(t)(-9.1 to-2.2)values,which are similar to those of the lower crustal granulitic metasedimentary and meta-igneous rocks in South China.Compared to other three plutons,the Shaziling pluton has consistentε_(Nd)(t)(-7.4 to-6.8)andε_(Hf)(t)(-7.5 to-4.7)values and shows similar source,but the Shaziling mafic microgranular enclaves(MMEs)show variableε_(Hf)(t)(-14.2 to 4.8)values,indicating a remarkable mantle magma injection of the Shaziling pluton.Zircon Ce/Sm-Yb/Gd,whole-rock CaO-P_(2)O_(5)and CaO-TiO_(2)linear trends reveal that from the Xishan to the Shaziling and from the Jinjiling to the Pangxiemu granites,they experienced apatite and titanite fractionation,respectively.Zircon Th,U,Nb,Ta,Hf,Ti,Y,P and rare earth element(REE)contents and whole-rock Sr,Ba and Rb contents also show that the Shaziling,Xishan,Jinjiling and Pangxiemu granites followed a discontinuous evolutionary series,but the Pangxiemu granites exhibit highly evolved nature.Four main controlling factors of W-Sn and rare metal mineralization in granitic rocks were discussed,and we found that the mineralization in Jiuyishan granitic complex was mainly controlled by the fractionation degree and crystallization temperature,but were rarely affected by oxygen fugacity and mantle material input.The Pangxiemu granites show particularly higher Rb and Ta contents than the other three plutons,implying that the ore deposits developed in the Jiuyishan Complex were directly related to the most evolved Pangxiemu pluton,with the occurrence of Rb and Ta as the most likely rare metal mineralization in the Jiuyishan District.A crystal mush model is proposed to interpret the petrogenetic and mineralizing processes of the Jiuyishan granitic complex. 展开更多
关键词 Jiuyishan granitic complex ZIRCON fractionation geochemistry rare metal mineralization
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^(99)mTc-MIBI皮肤放射性污染模型的对比研究
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作者 李培 李耀臻 +3 位作者 江继承 刘馨允 王学林 崔静 《医药论坛杂志》 2025年第3期225-230,共6页
目的建立在体的兔皮肤和离体的猪皮放射核素皮肤污染模型,对去污效能进行研究并与在体的人皮肤放射核素污染模型去污效能比对,为放射性核素污染模型的选择提供依据。方法用^(99)mTc-MIBI涂抹猪皮、兔和人的皮肤表面以建立离体和在体的... 目的建立在体的兔皮肤和离体的猪皮放射核素皮肤污染模型,对去污效能进行研究并与在体的人皮肤放射核素污染模型去污效能比对,为放射性核素污染模型的选择提供依据。方法用^(99)mTc-MIBI涂抹猪皮、兔和人的皮肤表面以建立离体和在体的放射性核素污染模型。三个组别中,每组再根据清洗方式和清洗时间不同,细分为清水组、洗手液组、清水延迟组和洗手液延迟组,共计12组。分别在污染后即刻和污染后延迟30 min进行5次、每次30s的持续流动水冲洗去污。用表面沾污仪检测每次清洗后的放射性计数并计算去污效能。比较猪皮、兔的即刻去污和延迟去污模型与人皮肤放射核素污染去污效能的差异。结果三组皮肤模型在放射性核素污染后,使用不同清洗方法在5个不同时间点去污效能的差异有统计学意义(F清水=640.822,P<0.001;F_(洗手液)=640.822,P<0.001;F_(清水延迟)=363.715,P<0.001;F_(洗手液延迟)=89.555,P<0.001),三组去污效能比较,人和兔差异无统计学意义(P_(清水)=0.395;P_(洗手液)=0.908;P_(清水)延迟=0.017;P_(洗手液)延迟=0.185);猪皮与其他两组差异均有统计学意义(P<0.001)。经5次清洗后,各模型组去污效能排序一致,依次为洗手液组、清水组、洗手液延迟组、清水延迟组。人皮肤和兔皮肤的清水和洗手液去污效能一致性较好(P_(人)=0.825;P_(兔)=0.629),清水延迟去污和洗手液延迟去污一致性较好(P_(人)=0.966;P_(兔)=0.727);猪皮肤四组去污效能一致性差异均有统计学意义(P<0.001)。兔皮肤和人皮肤的清洗效能达到或接近完全去污,而猪皮模型去污效能较差。结论三种模型的去污效能均随着清洗次数的增加而增加,兔和人的在体皮肤去污效能一致性较好,经过持续的清洗可达到或接近彻底去污。离体猪皮模型的去污效能明显减低,但在去污效能的趋势上与人皮肤有一致性。研究者可综合考虑试验目的和条件选择合适的皮肤放射性污染模型。 展开更多
关键词 99mtc-MIBI 皮肤放射性污染 去污效能 动物模型
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A phenylphenthiazide anchored Tb(Ⅲ)-cyclen complex for fluorescent turn-on sensing of ClO^(-) 被引量:1
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作者 Ya-Ping Liu Zhi-Rong Gui +4 位作者 Zhen-Wen Zhang Sai-Kang Wang Wei Lang Yanzhu Liu Qian-Yong Cao 《Chinese Chemical Letters》 2025年第2期269-273,共5页
A phenylphenothiazine anchored Tb(Ⅲ)-cyclen complex PTP-Cy-Tb for hypochlorite ion(ClO^(-))detection has been designed and prepared.PTP-Cy-Tb shows a weak Tb-based emission with AIE-characteristics in aqueous solutio... A phenylphenothiazine anchored Tb(Ⅲ)-cyclen complex PTP-Cy-Tb for hypochlorite ion(ClO^(-))detection has been designed and prepared.PTP-Cy-Tb shows a weak Tb-based emission with AIE-characteristics in aqueous solutions.After addition of ClO^(-),the fluorescence of PTP-Cy-Tb gives a large enhancement for oxidization the thioether to sulfoxide group.The detection limit of PTP-Cy-Tb toward ClO^(-)is as low as 8.85 nmol/L.The sensing mechanism was detailedly investigated by time of flight mass spectrometer(TOF-MS),Fourier transform infrared spectroscopy(FT-IR)and density functional theory(DFT)calculation.In addition,PTP-Cy-Tb has been successfully used for on-site and real-time detection of ClO^(-)in real water samples by using the smartphone-based visualization method and test strips. 展开更多
关键词 Phenylphenothiazine Tb(III)complex AIE Hypochlorite ion SENSING
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A mitochondria targeting Ir(Ⅲ)complex triggers ferroptosis and autophagy for cancer therapy:A case of aggregation enhanced PDT strategy for metal complexes 被引量:1
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作者 Panpan Wang Hongbao Fang +5 位作者 Mengmeng Wang Guandong Zhang Na Xu Yan Su Hongke Liu Zhi Su 《Chinese Chemical Letters》 2025年第1期374-380,共7页
Metal complexes hold significant promise in tumor diagnosis and treatment.However,their potential applications in photodynamic therapy(PDT)are hindered by issues such as poor photostability,low yield of reactive oxyge... Metal complexes hold significant promise in tumor diagnosis and treatment.However,their potential applications in photodynamic therapy(PDT)are hindered by issues such as poor photostability,low yield of reactive oxygen species(ROS),and aggregation-induced ROS quenching.To address these challenges,we present a molecular self-assembly strategy utilizing aggregation-induced emission(AIE)conjugates for metal complexes.As a proof of concept,we synthesized a mitochondrial-targeting cyclometalated Ir(Ⅲ)photosensitizer Ir-TPE.This approach significantly enhances the photodynamic effect while mitigating the dark toxicity associated with AIE groups.Ir-TPE readily self-assembles into nanoaggregates in aqueous solution,leading to a significant production of ROS upon light irradiation.Photoirradiated Ir-TPE triggers multiple modes of death by excessively accumulating ROS in the mitochondria,resulting in mitochondrial DNA damage.This damage can lead to ferroptosis and autophagy,two forms of cell death that are highly cytotoxic to cancer cells.The aggregation-enhanced photodynamic effect of Ir-TPE significantly enhances the production of ROS,leading to a more pronounced cytotoxic effect.In vitro and in vivo experiments demonstrate this aggregation-enhanced PDT approach achieves effective in situ tumor eradication.This study not only addresses the limitations of metal complexes in terms of low ROS production due to aggregation but also highlights the potential of this strategy for enhancing ROS production in PDT. 展开更多
关键词 Metal complex AIEgens Mitochondria targeting Enhanced photodynamic therapy Anticancer agent
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Synthesis and fluorescent properties of a one-dimensional Tb-calixarene complex as a luminescent thermometer material
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作者 PENG Dan WANG Hao +2 位作者 WANG Yanyan YOU Hongpeng LIAO Wuping 《无机化学学报》 北大核心 2025年第9期1859-1866,共8页
Luminescence thermometry has attracted more and more attention due to its non-contact and noninvasive operation,fast response,high spatial resolution,and so on,for which the luminescent thermometers are the key.Here,a... Luminescence thermometry has attracted more and more attention due to its non-contact and noninvasive operation,fast response,high spatial resolution,and so on,for which the luminescent thermometers are the key.Here,a 1D complex[Tb_(4)(HTC4A)(TC4A)(OBBA)_(2)(CH_(3)OH)_(4)(μ4-OH)]n(1)was obtained by solvothermal synthesis,where H 4TC4A=p-tert-butylthiacalix[4]arene,and H_(2)OBBA=4,4'-oxybisbenzoic acid.This complex is featured with a chain-like polymer constructed by bridging some sandwich-like Tb_(4)-(TC4A)_(2)entities through OBBA2-ligands.It exhibited the characteristic emission of the Tb^(3+)ion.Both fluorescence intensity and lifetime decreased with increasing temperature.The relative sensitivity was up to 8.743%·K^(-1)at 473 K,indicating it is a good ratiometric luminescent thermometer.This complex had good stability under different pH values and in common solvents.CCDC:2392643. 展开更多
关键词 TERBIUM CALIXARENES complexes luminescent thermometer
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Diversity,Complexity,and Challenges of Viral Infectious Disease Data in the Big Data Era:A Comprehensive Review 被引量:1
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作者 Yun Ma Lu-Yao Qin +1 位作者 Xiao Ding Ai-Ping Wu 《Chinese Medical Sciences Journal》 2025年第1期29-44,I0005,共17页
Viral infectious diseases,characterized by their intricate nature and wide-ranging diversity,pose substantial challenges in the domain of data management.The vast volume of data generated by these diseases,spanning fr... Viral infectious diseases,characterized by their intricate nature and wide-ranging diversity,pose substantial challenges in the domain of data management.The vast volume of data generated by these diseases,spanning from the molecular mechanisms within cells to large-scale epidemiological patterns,has surpassed the capabilities of traditional analytical methods.In the era of artificial intelligence(AI)and big data,there is an urgent necessity for the optimization of these analytical methods to more effectively handle and utilize the information.Despite the rapid accumulation of data associated with viral infections,the lack of a comprehensive framework for integrating,selecting,and analyzing these datasets has left numerous researchers uncertain about which data to select,how to access it,and how to utilize it most effectively in their research.This review endeavors to fill these gaps by exploring the multifaceted nature of viral infectious diseases and summarizing relevant data across multiple levels,from the molecular details of pathogens to broad epidemiological trends.The scope extends from the micro-scale to the macro-scale,encompassing pathogens,hosts,and vectors.In addition to data summarization,this review thoroughly investigates various dataset sources.It also traces the historical evolution of data collection in the field of viral infectious diseases,highlighting the progress achieved over time.Simultaneously,it evaluates the current limitations that impede data utilization.Furthermore,we propose strategies to surmount these challenges,focusing on the development and application of advanced computational techniques,AI-driven models,and enhanced data integration practices.By providing a comprehensive synthesis of existing knowledge,this review is designed to guide future research and contribute to more informed approaches in the surveillance,prevention,and control of viral infectious diseases,particularly within the context of the expanding big-data landscape. 展开更多
关键词 viral infectious diseases big data data diversity and complexity data standardization artificial intelligence data analysis
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Synthesis,crystal structure,thermal decomposition mechanism,and fluorescence properties of benzoic acid and 4-hydroxy-2,2′:6′,2″-terpyridine lanthanide complexes
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作者 HAN Yahui ZHAO Jinjin +1 位作者 REN Ning ZHANG Jianjun 《无机化学学报》 北大核心 2025年第5期969-982,共14页
Two novel lanthanide complexes,[Sm_(2)(BA)_(6)(4-OH-terpy)_(2)]·2H_(2)O·2EtOH(1)and[Pr_(2)(BA)_(6)(4-OH-terpy)_(2)(H_(2)O)_(2)]·HBA·H_(2)O(2),where HBA=benzoic acid,4-OH-terpy=4-hydroxy-2,2'∶6... Two novel lanthanide complexes,[Sm_(2)(BA)_(6)(4-OH-terpy)_(2)]·2H_(2)O·2EtOH(1)and[Pr_(2)(BA)_(6)(4-OH-terpy)_(2)(H_(2)O)_(2)]·HBA·H_(2)O(2),where HBA=benzoic acid,4-OH-terpy=4-hydroxy-2,2'∶6',2″-terpyridine,were successfully synthesized using ultrasonic dissolution and the conventional solution method with two mixed ligands HBA and 4-OH-terpy.During the synthesis,4-OH-terpy was involved in the reaction as a neutral ligand,while HBA,in its deprotonated form(BA-),coordinated with the lanthanide ions as an acidic ligand.The crystal structures of these two complexes were precisely determined by single-crystal X-ray diffraction.Elemental analysis,infrared and Raman spectroscopy,and powder X-ray diffraction techniques were also employed to further explore the physicochemical properties of the two complexes.The single-crystal X-ray diffraction data indicate that,despite their structural differences,both complexes belong to the triclinic crystal system P1 space group.The central lanthanide ions have the same coordination number but exhibit different coordination environments.To comprehensively evaluate the thermal stability of these two complexes,comprehensive tests including thermogravimetric analysis,differential thermogravimetric analysis,differential scanning calorimetry,Fourier transform infrared spectroscopy,and mass spectrometry were conducted.Meanwhile,an in-depth investigation was conducted into the 3D infrared stacked images and mass spectra of the gases emitted from the complexes.In addition,studies of the fluorescence properties of complex1 showed that it exhibited fluorescence emission matching the Sm^(3+)characteristic transition. 展开更多
关键词 lanthanide complexes crystal structure THERMOCHEMISTRY fluorescence spectrum
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低比活度^(99)Mo-^(99)mTc发生器研究进展
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作者 杨锐 舒俊翔 罗旭 《同位素》 2025年第1期48-55,共8页
^(99)mTc是由^(99)Mo进行β衰变产生的一种被广泛应用于核医学临床诊断领域的放射性同位素,主要通过母体核素^(99)Mo在发生器中衰变获得。由于核安全问题和多座生产^(99)Mo的反应堆相继关停,裂变^(99)Mo的供应量减少,导致裂变型色谱柱^(... ^(99)mTc是由^(99)Mo进行β衰变产生的一种被广泛应用于核医学临床诊断领域的放射性同位素,主要通过母体核素^(99)Mo在发生器中衰变获得。由于核安全问题和多座生产^(99)Mo的反应堆相继关停,裂变^(99)Mo的供应量减少,导致裂变型色谱柱^(99)Mo-^(99)mTc发生器的^(99)Mo原料来源困难,因此国内外积极推进低比活度的反应堆辐照和基于加速器的^(99)Mo生产技术及新型^(99)Mo-^(99)mTc发生器的研发。本文对低比活度^(99)Mo在国内的生产现状、国内外基于低比活度^(99)Mo开发的^(99)Mo/^(99)mTc分离方法和新型^(99)Mo-^(99)mTc发生器进行综述,以期为研发新型^(99)Mo-^(99)mTc发生器提供参考。 展开更多
关键词 低比活度 ^(99)Mo生产 ^(99)Mo-^(99)mtc发生器
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Parametric Dependence of Modified Yukawa Potential and Consequent Structure Changes of 2D Magnetized Complex Plasma
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作者 Li Xingyang Li Fei +2 位作者 Ma Jinghan Li Xinru Kong Wei 《南开大学学报(自然科学版)》 北大核心 2025年第2期78-86,共9页
For the magnetized complex plasma,dependences of modified Yukawa potential on the gov-erning parameters,viz.,mass ratio md/mi,number ratio nd/ne0,charge magnitude Q/e,and temperature ratio Te/Ti are investigated.It is... For the magnetized complex plasma,dependences of modified Yukawa potential on the gov-erning parameters,viz.,mass ratio md/mi,number ratio nd/ne0,charge magnitude Q/e,and temperature ratio Te/Ti are investigated.It is found that md/mi,nd/ne0 and Q/e contribute to the coupling strength of the system,and Te/Ti contributes to the shielding cloud surrounding the charged dust particles.Further analysis shows that the modified Yukawa potential depends on Te/Ti.The consequent structure changes of the system are discussed based on the Langevin dynamics simulation.It is found that the variation of Ham-iltonian contributes to the equilibrium structure of the system. 展开更多
关键词 complex plasma magnetic field modified Yukawa potential STRUCTURE
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Intramolecular Charge Transfer Complex Enabled Trifluoromethylation of Heteroarenes with Trifluoromethyl Phosphonium Salt
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作者 Liu Shuai Chen Kunquan +2 位作者 Sun Dequn Liu Qiang Chen Xiangyu 《有机化学》 北大核心 2025年第7期2545-2551,共7页
A photoinduced intramolecular charge transfer complex(ICTC)-enabled photoreduction of trifluoromethyl phosphonium salt for the trifluoromethylation of heteroarenes was developed.It offers a convenient approach to intr... A photoinduced intramolecular charge transfer complex(ICTC)-enabled photoreduction of trifluoromethyl phosphonium salt for the trifluoromethylation of heteroarenes was developed.It offers a convenient approach to introduce trifluoromethyl group to a wide range of aromatic heterocycles,such as indoles,pyrrole,substituted benzene,coumarin,and chromone.This strategy provides operational simplicity,photocatalyst-,transition metal-,and oxidant-free conditions,making it highly advantageous. 展开更多
关键词 trifluoromethyl phosphonium salt charge transfer complex TRIFLUOROMETHYLATION PHOTOINDUCED
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Photoinduced Decarboxylative Amination Driven by Electron Donor-Acceptor Complex
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作者 Gao Ang Yan Luyu +1 位作者 Wang Guangzu Fu Mingchen 《有机化学》 北大核心 2025年第5期1747-1754,共8页
A facile method for decarboxylative amination driven by the photoactivity of electron donor-acceptor(EDA)com-plexes assembled from iodide salts and redox-active esters has been proposed.A broad array of acyclic and cy... A facile method for decarboxylative amination driven by the photoactivity of electron donor-acceptor(EDA)com-plexes assembled from iodide salts and redox-active esters has been proposed.A broad array of acyclic and cyclic protected amines were readily synthesized without requiring exogenous transition-metal or photoredox catalysts.Moreover,this ap-proach facilitates late-stage functionalization of complex molecules and is amenable to continuous-flow process on gram scale. 展开更多
关键词 PHOTOREDOX decarboxylative amination iodine anion electron donor-acceptor complex
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In situ synthesis,crystal structure,and magnetic characterization of a trinuclear copper complex based on a multi-substituted imidazo[1,5-a]pyrazine scaffold
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作者 WANG Zhaodong 《无机化学学报》 北大核心 2025年第3期597-604,共8页
A trinuclear copper complex [Cu_(3)(L2)_(2)(SO_(4))_(2)(H_(2)O)_(7)]·8H_(2)O(1)(HL2=1-hydroxy-3-(pyrazin-2-yl)-N-(pyrazin-2-ylmethyl)imidazo[1,5-a]pyrazine-8-carboxamide) with a multi-substituted imidazo[1,5-a]py... A trinuclear copper complex [Cu_(3)(L2)_(2)(SO_(4))_(2)(H_(2)O)_(7)]·8H_(2)O(1)(HL2=1-hydroxy-3-(pyrazin-2-yl)-N-(pyrazin-2-ylmethyl)imidazo[1,5-a]pyrazine-8-carboxamide) with a multi-substituted imidazo[1,5-a]pyrazine scaffold was serendipitously prepared from the reaction of the pro-ligand of H_(2)L1(N,N'-bis(pyrazin-2-ylmethyl)pyrazine-2,3-dicarboxamide) with CuSO_(4)·5H_(2O) in aqueous solution at room temperature.Complex 1 was characterized by IR,single-crystal X-ray analysis,and magnetic susceptibility measurements.Single-crystal X-ray analysis reveals that the complex consists of three Cu(Ⅱ) ions,two in situ transformed L2~-ligands,two coordinated sulfates,seven coordinated water molecules,and eight uncoordinated water molecules.Magnetic susceptibility measurement indicates that there are obvious ferromagnetic coupling interactions between the adjacent Cu(Ⅱ) ions in 1.CCDC:1852713. 展开更多
关键词 amide ligand copper complex single crystal structure C-N coupling magnetic characterization
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Coordination equilibrium between cyclometalated Pt(Ⅱ)complexs[Pt(κ^(3)-N^C^N′)(CNXyl)]Cl and[Pt(κ^(2)-N^C^N′)(CNXyl)Cl]
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作者 ZHANG Huahong ZHAO Yang +2 位作者 NING Rui WU Shuixing ZHANG Xiaopeng 《无机化学学报》 北大核心 2025年第9期1840-1850,共11页
Reaction of the non-substituted/substituted unsymmetric pinene-derived complex[Pt(N^C^N')Cl]with the aryl isocyanide 2,6-dimethylphenyl isocyanide(CNXyl)afforded a mixture of two isomeric species:the ionic complex... Reaction of the non-substituted/substituted unsymmetric pinene-derived complex[Pt(N^C^N')Cl]with the aryl isocyanide 2,6-dimethylphenyl isocyanide(CNXyl)afforded a mixture of two isomeric species:the ionic complex[Pt(κ^(3)-N^C^N')(CNXyl)]Cl([A]Cl)and the molecular complex[Pt(κ^(2)-N^C^N')(CNXyl)Cl](B).Isomer B was almost the dominating product.The structures of the isomer B derivatives bearing-CF_(3)and-Cl substituents on the pyridine ring of the pinene moiety(5B and 7B,respectively)have been confirmed by single-crystal X-ray diffraction,revealing a slightly distorted square planar geometry with trans-N_(N^C^N'),CNR configuration(The terminal N atom of theκ^(2)-N^C^N'ligand is trans to the isocyanide ligand CNXyl.).Isomer B is thermodynamically more stable,as confirmed by theoretical calculations.CCDC:2416415,5B;2416414,7B. 展开更多
关键词 coordination equilibrium cyclometalated Pt(Ⅱ)complex isocyanide pinene group
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Ligand substitution of diiron hexacarbonyl complex with aminodiphosphine to prepare diiron aminophosphine complexes relevant to[FeFe]-hydrogenases
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作者 LIU Xufeng WANG Shaojie ZHAO Peihua 《无机化学学报》 北大核心 2025年第9期1851-1858,共8页
To extend a new family of aminophosphine-coordinated[FeFe]-hydrogenase mimics for catalytic hydro-gen(H_(2))evolution,we carried out the ligand substitutions of diiron hexacarbonyl precursors[Fe_(2)(μ-X_(2)pdt)(CO)_(... To extend a new family of aminophosphine-coordinated[FeFe]-hydrogenase mimics for catalytic hydro-gen(H_(2))evolution,we carried out the ligand substitutions of diiron hexacarbonyl precursors[Fe_(2)(μ-X_(2)pdt)(CO)_(6)](X_(2)pdt=(SCH_(2))_(2)CX_(2),X=Me,H)with aminodiphosphines(Ph_(2)PCH_(2))_(2)NY(Y=(CH_(2))_(2)OH,(CH_(2))_(3)OH)to obtain two new diiron aminophosphine complexes[Fe_(2)(L1)(μ-Me_(2)pdt)(CO)_(5)](1)and[Fe_(2)(L2)(μ-H_(2)pdt)(CO)_(5)](2),where L1=3-[(diphe-nylphosphaneyl)methyl]oxazolidine,L2=3-[(diphenylphosphaneyl)methyl]-1,3-oxazinane.Moreover,the structures of 1 and 2 have been fully confirmed by elemental analysis,spectroscopic techniques,and single-crystal X-ray diffraction.Using cyclic voltammetry(CV),we investigated the electrochemical redox performance and proton reduc-tion activities of 1 and 2 in acetic acid(HOAc).The CV study indicates that diiron aminophosphine complexes 1 and 2 can be considered to be hydrogenase-inspired diiron molecular electrocatalysts for the reduction of protons into H 2 generation in the presence of HOAc.CCDC:2443967,1;2443969,2. 展开更多
关键词 [FeFe]-hydrogenases diiron model complexes aminophosphine ligand STRUCTURE electrochemical performance
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Synthesis,structure,and magnetic property of a cobalt(Ⅱ)complex based on pyridyl⁃substituted imino nitroxide radical
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作者 WANG Xiaoling ZHANG Hongwu LIU Daofu 《无机化学学报》 北大核心 2025年第2期407-412,共6页
A new cobalt(Ⅱ)-radical complex:[Co(im4-py)_(2)(PNB)_(2)](im4-py=2-(4'-pyridyl)-4,4,5,5-tetramethylimidazole-1-oxyl,HPNB=p-nitrobenzoic acid)has been synthesized and characterized by X-ray diffraction analysis,el... A new cobalt(Ⅱ)-radical complex:[Co(im4-py)_(2)(PNB)_(2)](im4-py=2-(4'-pyridyl)-4,4,5,5-tetramethylimidazole-1-oxyl,HPNB=p-nitrobenzoic acid)has been synthesized and characterized by X-ray diffraction analysis,elemental analysis,IR,and magnetic properties.X-ray diffraction analysis shows that the complex exists as mononuclear molecules and Co(Ⅱ)ion is four-coordinated with two radicals and two PNB-ligands.The magnetic susceptibility study indicates the complex exhibits weak ferromagnetic interactions between cobalt(Ⅱ)and im4-py radical.The magnetic property is explained by the magnetic and structure exchange mechanism.CCDC:976028. 展开更多
关键词 Co(Ⅱ)complex imino nitroxide radical crystal structure magnetic property
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Multiscale structural complexity analysis of neuronal activity in suprachiasmatic nucleus:Insights from tetrodotoxin-induced disruptions
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作者 Ping Wang Changgui Gu Huijie Yang 《Chinese Physics B》 2025年第4期605-613,共9页
The suprachiasmatic nucleus in the hypothalamus is the master circadian clock in mammals,coordinating physiological processes with the 24-hour day–night cycle.Comprising various cell types,the suprachiasmatic nucleus... The suprachiasmatic nucleus in the hypothalamus is the master circadian clock in mammals,coordinating physiological processes with the 24-hour day–night cycle.Comprising various cell types,the suprachiasmatic nucleus(SCN)integrates environmental signals to maintain complex and robust circadian rhythms.Understanding the complexity and synchrony within SCN neurons is essential for effective circadian clock function.Synchrony involves coordinated neuronal firing for robust rhythms,while complexity reflects diverse activity patterns and interactions,indicating adaptability.Interestingly,the SCN retains circadian rhythms in vitro,demonstrating intrinsic rhythmicity.This study introduces the multiscale structural complexity method to analyze changes in SCN neuronal activity and complexity at macro and micro levels,based on Bagrov et al.’s approach.By examining structural complexity and local complexities across scales,we aim to understand how tetrodotoxin,a neurotoxin that inhibits action potentials,affects SCN neurons.Our method captures critical scales in neuronal interactions that traditional methods may overlook.Validation with the Goodwin model confirms the reliability of our observations.By integrating experimental data with theoretical models,this study provides new insights into the effects of tetrodotoxin(TTX)on neuronal complexities,contributing to the understanding of circadian rhythms. 展开更多
关键词 suprachiasmatic nucleus circadian rhythm complexITY synchrony multiscale structural complexity
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